Cutis

Isotretinoin was introduced more than 3 decades ago and marked a major advancement in the treatment of severe refractory cystic acne. The most common adverse effects linked to isotretinoin usage are mucocutaneous in nature, manifesting as xerosis and cheilitis.¹ Skin fragility and poor wound healing also have been reported.^2-6 Current recommendations for avoiding these adverse effects include refraining from waxing, laser procedures, and other elective cutaneous procedures for at least 6 months.⁷ We present a case of isotretinoin-induced cutaneous fragility resulting in blistering and erosions on the palms of a competitive aerial trapeze artist.

Case Report

A 25-year-old woman presented for follow-up during week 12 of isotretinoin therapy (40 mg twice daily) prescribed for acne. She reported peeling of the skin on the palms following intense aerial acrobatic workouts. She had been a performing aerialist for many years and had never sustained a similar injury. The wounds were painful and led to decreased activity. She had no notable medical history. Physical examination of the palms revealed erosions in a distribution that corresponded to horizontal bar contact and friction (Figure). The patient was advised on proper wound care, application of emollients, and minimizing friction. She completed the course of isotretinoin and has continued aerialist activity without recurrence of skin fragility.

Comment

Skin fragility is a well-known adverse effect of isotretinoin therapy.⁸ Pavlis and Lieblich⁹ reported skin fragility in a young wrestler who experienced similar skin erosions due to isotretinoin therapy. The proposed mechanism of isotretinoin-induced skin fragility is multifactorial. It involves an apoptotic effect on sebocytes,⁵ which results in reduced stratum corneum hydration and an associated increase in transepidermal water loss.^6,10,11 Retinoids also are known to cause thinning of the skin, likely due to the disadhesion of both the epidermis and the stratum corneum, which was demonstrated by the easy removal of cornified cells through tape stripping in hairless mice treated with isotretinoin.¹² In further investigations, human patients and hairless mice treated with isotretinoin readily developed friction blisters through pencil eraser abrasion.¹³ Examination of the friction blisters using light and electron microscopy revealed fraying or loss of the stratum corneum and viable epidermis as well as loss of desmosomes and tonofilaments. Additionally, intracellular and intercellular deposits of an unidentified amorphous material were noted.¹³

mawufroslijiphastophalocigofreliwunachusafregufrofraswidugoslehuvihucrebrisodrinimobiswosidibestephoprestumaswustech

Overall, the origin of skin fragility induced by isotretinoin is supported by its effect on sebocytes, increased transepidermal water loss, and profound disruption of the integrity of the epidermis, resulting in an elevated risk for inadvertent skin damage. Patients were encouraged to avoid cosmetic procedures in prior case reports,^14-16 and because our case demonstrates the risk for cutaneous injury in athletes due to isotretinoin-induced skin fragility, we propose an extension of these warnings to encompass athletes receiving isotretinoin treatment. Offering early guidance on wound prevention is of paramount importance in maintaining athletic performance and minimizing painful injuries.

Isotretinoin was introduced more than 3 decades ago and marked a major advancement in the treatment of severe refractory cystic acne. The most common adverse effects linked to isotretinoin usage are mucocutaneous in nature, manifesting as xerosis and cheilitis.¹ Skin fragility and poor wound healing also have been reported.^2-6 Current recommendations for avoiding these adverse effects include refraining from waxing, laser procedures, and other elective cutaneous procedures for at least 6 months.⁷ We present a case of isotretinoin-induced cutaneous fragility resulting in blistering and erosions on the palms of a competitive aerial trapeze artist.

Case Report

A 25-year-old woman presented for follow-up during week 12 of isotretinoin therapy (40 mg twice daily) prescribed for acne. She reported peeling of the skin on the palms following intense aerial acrobatic workouts. She had been a performing aerialist for many years and had never sustained a similar injury. The wounds were painful and led to decreased activity. She had no notable medical history. Physical examination of the palms revealed erosions in a distribution that corresponded to horizontal bar contact and friction (Figure). The patient was advised on proper wound care, application of emollients, and minimizing friction. She completed the course of isotretinoin and has continued aerialist activity without recurrence of skin fragility.

Comment

Skin fragility is a well-known adverse effect of isotretinoin therapy.⁸ Pavlis and Lieblich⁹ reported skin fragility in a young wrestler who experienced similar skin erosions due to isotretinoin therapy. The proposed mechanism of isotretinoin-induced skin fragility is multifactorial. It involves an apoptotic effect on sebocytes,⁵ which results in reduced stratum corneum hydration and an associated increase in transepidermal water loss.^6,10,11 Retinoids also are known to cause thinning of the skin, likely due to the disadhesion of both the epidermis and the stratum corneum, which was demonstrated by the easy removal of cornified cells through tape stripping in hairless mice treated with isotretinoin.¹² In further investigations, human patients and hairless mice treated with isotretinoin readily developed friction blisters through pencil eraser abrasion.¹³ Examination of the friction blisters using light and electron microscopy revealed fraying or loss of the stratum corneum and viable epidermis as well as loss of desmosomes and tonofilaments. Additionally, intracellular and intercellular deposits of an unidentified amorphous material were noted.¹³

mawufroslijiphastophalocigofreliwunachusafregufrofraswidugoslehuvihucrebrisodrinimobiswosidibestephoprestumaswustech

Overall, the origin of skin fragility induced by isotretinoin is supported by its effect on sebocytes, increased transepidermal water loss, and profound disruption of the integrity of the epidermis, resulting in an elevated risk for inadvertent skin damage. Patients were encouraged to avoid cosmetic procedures in prior case reports,^14-16 and because our case demonstrates the risk for cutaneous injury in athletes due to isotretinoin-induced skin fragility, we propose an extension of these warnings to encompass athletes receiving isotretinoin treatment. Offering early guidance on wound prevention is of paramount importance in maintaining athletic performance and minimizing painful injuries.

Isotretinoin was introduced more than 3 decades ago and marked a major advancement in the treatment of severe refractory cystic acne. The most common adverse effects linked to isotretinoin usage are mucocutaneous in nature, manifesting as xerosis and cheilitis.¹ Skin fragility and poor wound healing also have been reported.^2-6 Current recommendations for avoiding these adverse effects include refraining from waxing, laser procedures, and other elective cutaneous procedures for at least 6 months.⁷ We present a case of isotretinoin-induced cutaneous fragility resulting in blistering and erosions on the palms of a competitive aerial trapeze artist.

Case Report

A 25-year-old woman presented for follow-up during week 12 of isotretinoin therapy (40 mg twice daily) prescribed for acne. She reported peeling of the skin on the palms following intense aerial acrobatic workouts. She had been a performing aerialist for many years and had never sustained a similar injury. The wounds were painful and led to decreased activity. She had no notable medical history. Physical examination of the palms revealed erosions in a distribution that corresponded to horizontal bar contact and friction (Figure). The patient was advised on proper wound care, application of emollients, and minimizing friction. She completed the course of isotretinoin and has continued aerialist activity without recurrence of skin fragility.

Comment

Skin fragility is a well-known adverse effect of isotretinoin therapy.⁸ Pavlis and Lieblich⁹ reported skin fragility in a young wrestler who experienced similar skin erosions due to isotretinoin therapy. The proposed mechanism of isotretinoin-induced skin fragility is multifactorial. It involves an apoptotic effect on sebocytes,⁵ which results in reduced stratum corneum hydration and an associated increase in transepidermal water loss.^6,10,11 Retinoids also are known to cause thinning of the skin, likely due to the disadhesion of both the epidermis and the stratum corneum, which was demonstrated by the easy removal of cornified cells through tape stripping in hairless mice treated with isotretinoin.¹² In further investigations, human patients and hairless mice treated with isotretinoin readily developed friction blisters through pencil eraser abrasion.¹³ Examination of the friction blisters using light and electron microscopy revealed fraying or loss of the stratum corneum and viable epidermis as well as loss of desmosomes and tonofilaments. Additionally, intracellular and intercellular deposits of an unidentified amorphous material were noted.¹³

mawufroslijiphastophalocigofreliwunachusafregufrofraswidugoslehuvihucrebrisodrinimobiswosidibestephoprestumaswustech

Overall, the origin of skin fragility induced by isotretinoin is supported by its effect on sebocytes, increased transepidermal water loss, and profound disruption of the integrity of the epidermis, resulting in an elevated risk for inadvertent skin damage. Patients were encouraged to avoid cosmetic procedures in prior case reports,^14-16 and because our case demonstrates the risk for cutaneous injury in athletes due to isotretinoin-induced skin fragility, we propose an extension of these warnings to encompass athletes receiving isotretinoin treatment. Offering early guidance on wound prevention is of paramount importance in maintaining athletic performance and minimizing painful injuries.

Practice Gap

Epidermoid cysts are asymptomatic, well-circumscribed, mobile, subcutaneous masses that elevate the skin. Also known as epidermal, keratin, or infundibular cysts, epidermoid cysts are caused by proliferation of surface epidermoid cells within the dermis and can arise anywhere on the body, most commonly on the face, neck, and trunk.¹ Cutaneous cysts often contain fluid or semifluid contents and can be aesthetically displeasing or cause mild pain, prompting patients to seek removal. Definitive treatment of epidermoid cysts is complete surgical removal,² which can be performed in office in a sterile or clean manner by either dermatologists or primary care providers.

Prior to incision, a local anesthetic—commonly lidocaine with epinephrine—is injected in the region surrounding the cyst sac so as not to rupture the cyst wall. Maintaining the cyst wall throughout the procedure ensures total cyst removal and minimizes the risk for recurrence. However, it often is difficult to approximate the cyst border because it cannot be visualized prior to incision.

Throughout the duration of the procedure, cyst contents may suddenly spray out of the area and pose a risk to providers and their staff (Figure, A). Even with careful application around the periphery, either puncture or ­pericystic anesthesia between the cyst wall and the dermis can lead to splatter. Larger and wider peripheral anesthesia may not be possible given a shortage of ­lidocaine and a desire to minimize injection. Even with meticulous use of personal protective equipment in cutaneous surgery, infectious organisms found in ruptured cysts and abscesses may spray the surgical field.³ Therefore, it is in our best interest to minimize the trajectory of cyst spray contents.

The Tools

We have employed 2 simple techniques using equipment normally found on a standard surgical tray for easy safe injection of cysts. Supplies needed include 4×4-inch gauze pads, alcohol and chlorhexidine, a marker, all instruments necessary for cyst excision, and a small clear biohazard bag.

The Technique

Prior to covering the cyst, care is taken to locate the cyst opening. At times, a comedo or punctum can be seen overlying the cyst bulge. We mark the lumen and cyst opening with a surgical marker. If the pore is not easily identified, we draw an 8-mm circle around the mound of the cyst. 

One option is to apply a gauze pad over the cyst to allow for stabilization of the surgical field and blanket the area from splatter (Figure, B). Then we cover the cyst using antiseptic-soaked gauze as a protective barrier to avoid potentially contaminated spray. This tool can be constructed from a 4×4-inch gauze pad with the addition of alcohol and chlorhexidine. When the cyst is covered, the surgeon can inject the lesion and surrounding tissue without biohazard splatter.

cashefrakowrupehaswebratroclabraveshepoviwrustahodefretradislecrukiwricathobuneuakucliclispocranufridrawikegowuchobubatospuuislomuduruclukisewawrauistibrestithouireshojekobrowrespushuruhophojitifrustuchuni

Practice Implications

Outpatient surgical excision is a common effective procedure for epidermoid cysts. However, it is not uncommon for cyst contents to spray during the injection of anesthetic, posing a nuisance to the surgeon, health care staff, and patient. The technique of covering the lesion with antiseptic-soaked gauze or a small clear biohazard bag prevents cyst contents from spraying and reduces risk for contamination. In addition to these protective benefits, the use of readily available items replaces the need to order a splatter control shield.

Limitations—Although we seldom see spray using our technique, covering the cyst with gauze may disguise the region of interest and interfere with accurate incision. Marking the lesion prior to anesthesia administration or using a clear biohazard bag minimizes difficulty visualizing the cyst opening.

Practice Gap

Epidermoid cysts are asymptomatic, well-circumscribed, mobile, subcutaneous masses that elevate the skin. Also known as epidermal, keratin, or infundibular cysts, epidermoid cysts are caused by proliferation of surface epidermoid cells within the dermis and can arise anywhere on the body, most commonly on the face, neck, and trunk.¹ Cutaneous cysts often contain fluid or semifluid contents and can be aesthetically displeasing or cause mild pain, prompting patients to seek removal. Definitive treatment of epidermoid cysts is complete surgical removal,² which can be performed in office in a sterile or clean manner by either dermatologists or primary care providers.

Prior to incision, a local anesthetic—commonly lidocaine with epinephrine—is injected in the region surrounding the cyst sac so as not to rupture the cyst wall. Maintaining the cyst wall throughout the procedure ensures total cyst removal and minimizes the risk for recurrence. However, it often is difficult to approximate the cyst border because it cannot be visualized prior to incision.

Throughout the duration of the procedure, cyst contents may suddenly spray out of the area and pose a risk to providers and their staff (Figure, A). Even with careful application around the periphery, either puncture or ­pericystic anesthesia between the cyst wall and the dermis can lead to splatter. Larger and wider peripheral anesthesia may not be possible given a shortage of ­lidocaine and a desire to minimize injection. Even with meticulous use of personal protective equipment in cutaneous surgery, infectious organisms found in ruptured cysts and abscesses may spray the surgical field.³ Therefore, it is in our best interest to minimize the trajectory of cyst spray contents.

The Tools

We have employed 2 simple techniques using equipment normally found on a standard surgical tray for easy safe injection of cysts. Supplies needed include 4×4-inch gauze pads, alcohol and chlorhexidine, a marker, all instruments necessary for cyst excision, and a small clear biohazard bag.

The Technique

Prior to covering the cyst, care is taken to locate the cyst opening. At times, a comedo or punctum can be seen overlying the cyst bulge. We mark the lumen and cyst opening with a surgical marker. If the pore is not easily identified, we draw an 8-mm circle around the mound of the cyst. 

One option is to apply a gauze pad over the cyst to allow for stabilization of the surgical field and blanket the area from splatter (Figure, B). Then we cover the cyst using antiseptic-soaked gauze as a protective barrier to avoid potentially contaminated spray. This tool can be constructed from a 4×4-inch gauze pad with the addition of alcohol and chlorhexidine. When the cyst is covered, the surgeon can inject the lesion and surrounding tissue without biohazard splatter.

cashefrakowrupehaswebratroclabraveshepoviwrustahodefretradislecrukiwricathobuneuakucliclispocranufridrawikegowuchobubatospuuislomuduruclukisewawrauistibrestithouireshojekobrowrespushuruhophojitifrustuchuni

Practice Implications

Outpatient surgical excision is a common effective procedure for epidermoid cysts. However, it is not uncommon for cyst contents to spray during the injection of anesthetic, posing a nuisance to the surgeon, health care staff, and patient. The technique of covering the lesion with antiseptic-soaked gauze or a small clear biohazard bag prevents cyst contents from spraying and reduces risk for contamination. In addition to these protective benefits, the use of readily available items replaces the need to order a splatter control shield.

Limitations—Although we seldom see spray using our technique, covering the cyst with gauze may disguise the region of interest and interfere with accurate incision. Marking the lesion prior to anesthesia administration or using a clear biohazard bag minimizes difficulty visualizing the cyst opening.

Practice Gap

Epidermoid cysts are asymptomatic, well-circumscribed, mobile, subcutaneous masses that elevate the skin. Also known as epidermal, keratin, or infundibular cysts, epidermoid cysts are caused by proliferation of surface epidermoid cells within the dermis and can arise anywhere on the body, most commonly on the face, neck, and trunk.¹ Cutaneous cysts often contain fluid or semifluid contents and can be aesthetically displeasing or cause mild pain, prompting patients to seek removal. Definitive treatment of epidermoid cysts is complete surgical removal,² which can be performed in office in a sterile or clean manner by either dermatologists or primary care providers.

Prior to incision, a local anesthetic—commonly lidocaine with epinephrine—is injected in the region surrounding the cyst sac so as not to rupture the cyst wall. Maintaining the cyst wall throughout the procedure ensures total cyst removal and minimizes the risk for recurrence. However, it often is difficult to approximate the cyst border because it cannot be visualized prior to incision.

Throughout the duration of the procedure, cyst contents may suddenly spray out of the area and pose a risk to providers and their staff (Figure, A). Even with careful application around the periphery, either puncture or ­pericystic anesthesia between the cyst wall and the dermis can lead to splatter. Larger and wider peripheral anesthesia may not be possible given a shortage of ­lidocaine and a desire to minimize injection. Even with meticulous use of personal protective equipment in cutaneous surgery, infectious organisms found in ruptured cysts and abscesses may spray the surgical field.³ Therefore, it is in our best interest to minimize the trajectory of cyst spray contents.

The Tools

We have employed 2 simple techniques using equipment normally found on a standard surgical tray for easy safe injection of cysts. Supplies needed include 4×4-inch gauze pads, alcohol and chlorhexidine, a marker, all instruments necessary for cyst excision, and a small clear biohazard bag.

The Technique

Prior to covering the cyst, care is taken to locate the cyst opening. At times, a comedo or punctum can be seen overlying the cyst bulge. We mark the lumen and cyst opening with a surgical marker. If the pore is not easily identified, we draw an 8-mm circle around the mound of the cyst. 

One option is to apply a gauze pad over the cyst to allow for stabilization of the surgical field and blanket the area from splatter (Figure, B). Then we cover the cyst using antiseptic-soaked gauze as a protective barrier to avoid potentially contaminated spray. This tool can be constructed from a 4×4-inch gauze pad with the addition of alcohol and chlorhexidine. When the cyst is covered, the surgeon can inject the lesion and surrounding tissue without biohazard splatter.

cashefrakowrupehaswebratroclabraveshepoviwrustahodefretradislecrukiwricathobuneuakucliclispocranufridrawikegowuchobubatospuuislomuduruclukisewawrauistibrestithouireshojekobrowrespushuruhophojitifrustuchuni

Practice Implications

Outpatient surgical excision is a common effective procedure for epidermoid cysts. However, it is not uncommon for cyst contents to spray during the injection of anesthetic, posing a nuisance to the surgeon, health care staff, and patient. The technique of covering the lesion with antiseptic-soaked gauze or a small clear biohazard bag prevents cyst contents from spraying and reduces risk for contamination. In addition to these protective benefits, the use of readily available items replaces the need to order a splatter control shield.

Limitations—Although we seldom see spray using our technique, covering the cyst with gauze may disguise the region of interest and interfere with accurate incision. Marking the lesion prior to anesthesia administration or using a clear biohazard bag minimizes difficulty visualizing the cyst opening.

The Diagnosis: Congenital Hemangioma

Surgical resection of the mass was performed at 4 months of age without complication (Figure 1). Histopathology revealed a lobular endothelial cell proliferation within a densely fibrotic stroma, multiple thin-walled vessels, and negative immunoreactivity to glucose transporter type 1 (GLUT-1)(Figures 2 and 3). Combined with the patient’s clinical history and findings on imaging (Figure 4), the most accurate diagnosis was a congenital hemangioma (CH). The mass was determined to be a noninvoluting congenital hemangioma (NICH).

A variety of vascular anomalies manifest in newborns and can be differentiated by the patient’s clinical history—particularly whether the lesion is present at birth or develops after birth. Imaging and histopathology of the lesion(s) may be utilized when clinical examination alone is not sufficient to make a diagnosis. Histopathology and immunohistochemistry further aid in differentiating the type of vascular lesion.

praslelophobririmachegatiphinukiswicravitestoclislogutrustehecleruueshapithedrodrouumagupade

tuvathutetisipusloshuthefruphesteberusajiuocinufrasluthochetrivudrilawrapinafritresothestathiswushistasiwrajisle

Overall, vascular anomalies are classified broadly into 2 categories based on their pathogenesis: tumors and malformations. Vascular tumors are composed of proliferating endothelial cells that have the potential to resolve spontaneously over time. Examples include CH, infantile hemangioma (IH), kaposiform hemangioendothelioma (KHE), and tufted angioma (TA). In contrast, vascular malformations (ie, arteriovenous malformations) are composed of dysplastic vessels with normal endothelial cell turnover and do not resolve without intervention.¹

Congenital hemangiomas are rare vascular tumors that are fully developed at birth. These tumors proliferate in utero, enabling prenatal detection via ultrasonography as early as 12 weeks’ gestation for large heterogeneous vascular masses.^2-4 Congenital hemangiomas are described as solitary, well-circumscribed, raised, violaceous lesions most commonly located in the head and neck region.^4-6 Histopathologically, they are characterized by lobules of proliferating capillaries surrounded by fibrous stroma and dysplastic vascular channels.^6,7

Congenital hemangiomas are categorized based on their postnatal involution patterns.2 Fetally involuting CH both develops and begins regression in utero and often is completely regressed at birth.⁸ Rapidly involuting CH begins regression in the first few weeks of life and usually is completely involuted by 14 months of age.6,9-11 Conversely, NICH does not regress, often requiring surgical excision due to functional and cosmetic issues.^12,13 Partially involuting CH is intermediary, beginning as rapidly involuting but not involuting completely and persisting as lesions that resemble NICH.^14-16 Although generally benign and asymptomatic, these tumors can cause transient thrombocytopenia and coagulopathy at birth, as seen in our patient.^17,18

chocrefruthumisliuedodrolubathegodithahichoneclibrujaracrichupuclawrumagatidru

tafrejuthemahitaroswotriswadodocrumobruwratuclothohospithebibrothiwewamuswuprirerotrupithuvapifrowratuwuthuswuwrapresweslitreclathefrinostutrupreuastuluswidrevipuminam

Infantile hemangioma is the most common vascular tumor of infancy.^19-21 Although a precursor lesion may be present at birth, generally this tumor becomes apparent after the first few weeks of life as a solitary vascular plaque or nodule with a predilection for the head and neck.^22-25 Once it arises, IH quickly enters a period of rapid growth, followed by a period of slower continued growth, with most reaching maximum size by 3 months.²² Thereafter, IH enters a slow period of involution (range, 3–9 years)²⁶; more recent data suggest near resolution by 5 years of age.²⁷ Infantile hemangioma is categorized based on its depth in the skin and subcutaneous tissues and can be classified as superficial, mixed, or deep.^22,24,28,29 Superficial IH appears as a red plaque and may exhibit lobulation, while deep IH can be identified as flesh-colored or blue subcutaneous masses. Mixed IH may manifest with both superficial and deep features depending on the extent of its involvement in the dermal and subcutaneous layers. The pattern of involvement may be focal, segmental, or indeterminate.²⁴ In contrast, CH typically is a solitary vascular mass with prominent telangiectases, nodules, and radiating veins.⁶ Histologically, IH is composed of proliferative plump endothelial cells that form capillaries, and the lesion stains positively for GLUT-1, whereas CH does not.³⁰

Kaposiform hemangioendothelioma is classified as a locally aggressive vascular tumor that manifests either prenatally or in early infancy.³¹ It is described as a solitary, ill-defined, firm, purple plaque most commonly located on the extremities and retroperitoneum.^32-34 Histopathologically, these lesions are characterized by dilated lymphatic channels and irregular sheets or lobules of spindle-shaped endothelial cells infiltrating the dermis and subcutaneous fat.^33,35 In contrast to CH, KHE lesions show immunoreactivity to the markers podoplanin, lymphatic vessel endothelial receptor 1, and prospero homeobox 1 protein.^36,37 Notably, 70% of these tumors are complicated by the presence of Kasabach-Merritt phenomenon, a potentially life-threatening emergency that occurs when platelets are trapped within a vascular tumor, leading to the consumption of clotting factors, intralesional bleeding, and rapid enlargement of the tumor.³² The Kasabach-Merritt phenomenon manifests clinically as microangiopathic hemolytic anemia, severe thrombocytopenia, and disseminated intravascular coagulation. ³⁸ Although CH lesions also can be associated with thrombocytopenia and coagulopathy, they generally are mild and self-limited.¹⁸

Tufted angioma is a vascular tumor that arises within the first 5 years of life as firm violaceous papules or plaques, often with associated hyperhidrosis or hypertrichosis.^39,40 Although TA grows slowly for a period of time, it eventually stabilizes and persists, rarely regressing completely.⁴¹ These tumors share many similarities with KHE, and it has been suggested that they may be part of the same spectrum. 42 As with KHE, TA lesions show immunoreactivity to the markers podoplanin, lymphatic vessel endothelial receptor 1, and prospero homeobox 1 protein, which are negative in CH.^36,37 Although TA also can be complicated by Kasabach-Merritt phenomenon, the incidence is much lower (up to 38%).^43,44 As such, TAs tend to be recognized as more superficial benign lesions. However, they still can cause notable cosmetic and functional impairment and should be monitored closely, especially in the presence of associated symptoms or complications.

Arteriovenous malformation is a vascular lesion that results from errors during the embryonic development of vascular channels.⁴⁵ Although present at birth, it may not become clinically apparent until later in life. Arteriovenous malformations enlarge postnatally, and their growth is proportional to the developmental growth of the affected individual rather than the result of endothelial proliferation.⁴⁶ In infants, AVM may manifest as a faint vascular stain that can evolve over time into a pink patch associated with a palpable thrill during adolescence. ⁴ On Doppler flow imaging, AVMs are identified as fast-flow anomalies arising from an abnormal communication between high-pressure arterial systems and low-pressure venous systems without the presence of a capillary bed.⁴⁷ One of the differentiating factors between AVM and CH is that AVMs do not regress spontaneously and tend to have high recurrence rates, even with intervention. ⁴⁸ In contrast, CH can be categorized based on its postnatal involution pattern. Another distinguishing factor is that AVMs tend to be larger and more invasive than CHs.⁴⁶ Therefore, early diagnosis and intervention are crucial to prevent complications such as bleeding, seizures, or neurologic deficits associated with AVMs.¹

The Diagnosis: Congenital Hemangioma

Surgical resection of the mass was performed at 4 months of age without complication (Figure 1). Histopathology revealed a lobular endothelial cell proliferation within a densely fibrotic stroma, multiple thin-walled vessels, and negative immunoreactivity to glucose transporter type 1 (GLUT-1)(Figures 2 and 3). Combined with the patient’s clinical history and findings on imaging (Figure 4), the most accurate diagnosis was a congenital hemangioma (CH). The mass was determined to be a noninvoluting congenital hemangioma (NICH).

A variety of vascular anomalies manifest in newborns and can be differentiated by the patient’s clinical history—particularly whether the lesion is present at birth or develops after birth. Imaging and histopathology of the lesion(s) may be utilized when clinical examination alone is not sufficient to make a diagnosis. Histopathology and immunohistochemistry further aid in differentiating the type of vascular lesion.

praslelophobririmachegatiphinukiswicravitestoclislogutrustehecleruueshapithedrodrouumagupade

tuvathutetisipusloshuthefruphesteberusajiuocinufrasluthochetrivudrilawrapinafritresothestathiswushistasiwrajisle

Overall, vascular anomalies are classified broadly into 2 categories based on their pathogenesis: tumors and malformations. Vascular tumors are composed of proliferating endothelial cells that have the potential to resolve spontaneously over time. Examples include CH, infantile hemangioma (IH), kaposiform hemangioendothelioma (KHE), and tufted angioma (TA). In contrast, vascular malformations (ie, arteriovenous malformations) are composed of dysplastic vessels with normal endothelial cell turnover and do not resolve without intervention.¹

Congenital hemangiomas are rare vascular tumors that are fully developed at birth. These tumors proliferate in utero, enabling prenatal detection via ultrasonography as early as 12 weeks’ gestation for large heterogeneous vascular masses.^2-4 Congenital hemangiomas are described as solitary, well-circumscribed, raised, violaceous lesions most commonly located in the head and neck region.^4-6 Histopathologically, they are characterized by lobules of proliferating capillaries surrounded by fibrous stroma and dysplastic vascular channels.^6,7

Congenital hemangiomas are categorized based on their postnatal involution patterns.2 Fetally involuting CH both develops and begins regression in utero and often is completely regressed at birth.⁸ Rapidly involuting CH begins regression in the first few weeks of life and usually is completely involuted by 14 months of age.6,9-11 Conversely, NICH does not regress, often requiring surgical excision due to functional and cosmetic issues.^12,13 Partially involuting CH is intermediary, beginning as rapidly involuting but not involuting completely and persisting as lesions that resemble NICH.^14-16 Although generally benign and asymptomatic, these tumors can cause transient thrombocytopenia and coagulopathy at birth, as seen in our patient.^17,18

chocrefruthumisliuedodrolubathegodithahichoneclibrujaracrichupuclawrumagatidru

tafrejuthemahitaroswotriswadodocrumobruwratuclothohospithebibrothiwewamuswuprirerotrupithuvapifrowratuwuthuswuwrapresweslitreclathefrinostutrupreuastuluswidrevipuminam

Infantile hemangioma is the most common vascular tumor of infancy.^19-21 Although a precursor lesion may be present at birth, generally this tumor becomes apparent after the first few weeks of life as a solitary vascular plaque or nodule with a predilection for the head and neck.^22-25 Once it arises, IH quickly enters a period of rapid growth, followed by a period of slower continued growth, with most reaching maximum size by 3 months.²² Thereafter, IH enters a slow period of involution (range, 3–9 years)²⁶; more recent data suggest near resolution by 5 years of age.²⁷ Infantile hemangioma is categorized based on its depth in the skin and subcutaneous tissues and can be classified as superficial, mixed, or deep.^22,24,28,29 Superficial IH appears as a red plaque and may exhibit lobulation, while deep IH can be identified as flesh-colored or blue subcutaneous masses. Mixed IH may manifest with both superficial and deep features depending on the extent of its involvement in the dermal and subcutaneous layers. The pattern of involvement may be focal, segmental, or indeterminate.²⁴ In contrast, CH typically is a solitary vascular mass with prominent telangiectases, nodules, and radiating veins.⁶ Histologically, IH is composed of proliferative plump endothelial cells that form capillaries, and the lesion stains positively for GLUT-1, whereas CH does not.³⁰

Kaposiform hemangioendothelioma is classified as a locally aggressive vascular tumor that manifests either prenatally or in early infancy.³¹ It is described as a solitary, ill-defined, firm, purple plaque most commonly located on the extremities and retroperitoneum.^32-34 Histopathologically, these lesions are characterized by dilated lymphatic channels and irregular sheets or lobules of spindle-shaped endothelial cells infiltrating the dermis and subcutaneous fat.^33,35 In contrast to CH, KHE lesions show immunoreactivity to the markers podoplanin, lymphatic vessel endothelial receptor 1, and prospero homeobox 1 protein.^36,37 Notably, 70% of these tumors are complicated by the presence of Kasabach-Merritt phenomenon, a potentially life-threatening emergency that occurs when platelets are trapped within a vascular tumor, leading to the consumption of clotting factors, intralesional bleeding, and rapid enlargement of the tumor.³² The Kasabach-Merritt phenomenon manifests clinically as microangiopathic hemolytic anemia, severe thrombocytopenia, and disseminated intravascular coagulation. ³⁸ Although CH lesions also can be associated with thrombocytopenia and coagulopathy, they generally are mild and self-limited.¹⁸

Tufted angioma is a vascular tumor that arises within the first 5 years of life as firm violaceous papules or plaques, often with associated hyperhidrosis or hypertrichosis.^39,40 Although TA grows slowly for a period of time, it eventually stabilizes and persists, rarely regressing completely.⁴¹ These tumors share many similarities with KHE, and it has been suggested that they may be part of the same spectrum. 42 As with KHE, TA lesions show immunoreactivity to the markers podoplanin, lymphatic vessel endothelial receptor 1, and prospero homeobox 1 protein, which are negative in CH.^36,37 Although TA also can be complicated by Kasabach-Merritt phenomenon, the incidence is much lower (up to 38%).^43,44 As such, TAs tend to be recognized as more superficial benign lesions. However, they still can cause notable cosmetic and functional impairment and should be monitored closely, especially in the presence of associated symptoms or complications.

Arteriovenous malformation is a vascular lesion that results from errors during the embryonic development of vascular channels.⁴⁵ Although present at birth, it may not become clinically apparent until later in life. Arteriovenous malformations enlarge postnatally, and their growth is proportional to the developmental growth of the affected individual rather than the result of endothelial proliferation.⁴⁶ In infants, AVM may manifest as a faint vascular stain that can evolve over time into a pink patch associated with a palpable thrill during adolescence. ⁴ On Doppler flow imaging, AVMs are identified as fast-flow anomalies arising from an abnormal communication between high-pressure arterial systems and low-pressure venous systems without the presence of a capillary bed.⁴⁷ One of the differentiating factors between AVM and CH is that AVMs do not regress spontaneously and tend to have high recurrence rates, even with intervention. ⁴⁸ In contrast, CH can be categorized based on its postnatal involution pattern. Another distinguishing factor is that AVMs tend to be larger and more invasive than CHs.⁴⁶ Therefore, early diagnosis and intervention are crucial to prevent complications such as bleeding, seizures, or neurologic deficits associated with AVMs.¹

The Diagnosis: Congenital Hemangioma

Surgical resection of the mass was performed at 4 months of age without complication (Figure 1). Histopathology revealed a lobular endothelial cell proliferation within a densely fibrotic stroma, multiple thin-walled vessels, and negative immunoreactivity to glucose transporter type 1 (GLUT-1)(Figures 2 and 3). Combined with the patient’s clinical history and findings on imaging (Figure 4), the most accurate diagnosis was a congenital hemangioma (CH). The mass was determined to be a noninvoluting congenital hemangioma (NICH).

A variety of vascular anomalies manifest in newborns and can be differentiated by the patient’s clinical history—particularly whether the lesion is present at birth or develops after birth. Imaging and histopathology of the lesion(s) may be utilized when clinical examination alone is not sufficient to make a diagnosis. Histopathology and immunohistochemistry further aid in differentiating the type of vascular lesion.

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tuvathutetisipusloshuthefruphesteberusajiuocinufrasluthochetrivudrilawrapinafritresothestathiswushistasiwrajisle

Overall, vascular anomalies are classified broadly into 2 categories based on their pathogenesis: tumors and malformations. Vascular tumors are composed of proliferating endothelial cells that have the potential to resolve spontaneously over time. Examples include CH, infantile hemangioma (IH), kaposiform hemangioendothelioma (KHE), and tufted angioma (TA). In contrast, vascular malformations (ie, arteriovenous malformations) are composed of dysplastic vessels with normal endothelial cell turnover and do not resolve without intervention.¹

Congenital hemangiomas are rare vascular tumors that are fully developed at birth. These tumors proliferate in utero, enabling prenatal detection via ultrasonography as early as 12 weeks’ gestation for large heterogeneous vascular masses.^2-4 Congenital hemangiomas are described as solitary, well-circumscribed, raised, violaceous lesions most commonly located in the head and neck region.^4-6 Histopathologically, they are characterized by lobules of proliferating capillaries surrounded by fibrous stroma and dysplastic vascular channels.^6,7

Congenital hemangiomas are categorized based on their postnatal involution patterns.2 Fetally involuting CH both develops and begins regression in utero and often is completely regressed at birth.⁸ Rapidly involuting CH begins regression in the first few weeks of life and usually is completely involuted by 14 months of age.6,9-11 Conversely, NICH does not regress, often requiring surgical excision due to functional and cosmetic issues.^12,13 Partially involuting CH is intermediary, beginning as rapidly involuting but not involuting completely and persisting as lesions that resemble NICH.^14-16 Although generally benign and asymptomatic, these tumors can cause transient thrombocytopenia and coagulopathy at birth, as seen in our patient.^17,18

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Infantile hemangioma is the most common vascular tumor of infancy.^19-21 Although a precursor lesion may be present at birth, generally this tumor becomes apparent after the first few weeks of life as a solitary vascular plaque or nodule with a predilection for the head and neck.^22-25 Once it arises, IH quickly enters a period of rapid growth, followed by a period of slower continued growth, with most reaching maximum size by 3 months.²² Thereafter, IH enters a slow period of involution (range, 3–9 years)²⁶; more recent data suggest near resolution by 5 years of age.²⁷ Infantile hemangioma is categorized based on its depth in the skin and subcutaneous tissues and can be classified as superficial, mixed, or deep.^22,24,28,29 Superficial IH appears as a red plaque and may exhibit lobulation, while deep IH can be identified as flesh-colored or blue subcutaneous masses. Mixed IH may manifest with both superficial and deep features depending on the extent of its involvement in the dermal and subcutaneous layers. The pattern of involvement may be focal, segmental, or indeterminate.²⁴ In contrast, CH typically is a solitary vascular mass with prominent telangiectases, nodules, and radiating veins.⁶ Histologically, IH is composed of proliferative plump endothelial cells that form capillaries, and the lesion stains positively for GLUT-1, whereas CH does not.³⁰

Kaposiform hemangioendothelioma is classified as a locally aggressive vascular tumor that manifests either prenatally or in early infancy.³¹ It is described as a solitary, ill-defined, firm, purple plaque most commonly located on the extremities and retroperitoneum.^32-34 Histopathologically, these lesions are characterized by dilated lymphatic channels and irregular sheets or lobules of spindle-shaped endothelial cells infiltrating the dermis and subcutaneous fat.^33,35 In contrast to CH, KHE lesions show immunoreactivity to the markers podoplanin, lymphatic vessel endothelial receptor 1, and prospero homeobox 1 protein.^36,37 Notably, 70% of these tumors are complicated by the presence of Kasabach-Merritt phenomenon, a potentially life-threatening emergency that occurs when platelets are trapped within a vascular tumor, leading to the consumption of clotting factors, intralesional bleeding, and rapid enlargement of the tumor.³² The Kasabach-Merritt phenomenon manifests clinically as microangiopathic hemolytic anemia, severe thrombocytopenia, and disseminated intravascular coagulation. ³⁸ Although CH lesions also can be associated with thrombocytopenia and coagulopathy, they generally are mild and self-limited.¹⁸

Tufted angioma is a vascular tumor that arises within the first 5 years of life as firm violaceous papules or plaques, often with associated hyperhidrosis or hypertrichosis.^39,40 Although TA grows slowly for a period of time, it eventually stabilizes and persists, rarely regressing completely.⁴¹ These tumors share many similarities with KHE, and it has been suggested that they may be part of the same spectrum. 42 As with KHE, TA lesions show immunoreactivity to the markers podoplanin, lymphatic vessel endothelial receptor 1, and prospero homeobox 1 protein, which are negative in CH.^36,37 Although TA also can be complicated by Kasabach-Merritt phenomenon, the incidence is much lower (up to 38%).^43,44 As such, TAs tend to be recognized as more superficial benign lesions. However, they still can cause notable cosmetic and functional impairment and should be monitored closely, especially in the presence of associated symptoms or complications.

Arteriovenous malformation is a vascular lesion that results from errors during the embryonic development of vascular channels.⁴⁵ Although present at birth, it may not become clinically apparent until later in life. Arteriovenous malformations enlarge postnatally, and their growth is proportional to the developmental growth of the affected individual rather than the result of endothelial proliferation.⁴⁶ In infants, AVM may manifest as a faint vascular stain that can evolve over time into a pink patch associated with a palpable thrill during adolescence. ⁴ On Doppler flow imaging, AVMs are identified as fast-flow anomalies arising from an abnormal communication between high-pressure arterial systems and low-pressure venous systems without the presence of a capillary bed.⁴⁷ One of the differentiating factors between AVM and CH is that AVMs do not regress spontaneously and tend to have high recurrence rates, even with intervention. ⁴⁸ In contrast, CH can be categorized based on its postnatal involution pattern. Another distinguishing factor is that AVMs tend to be larger and more invasive than CHs.⁴⁶ Therefore, early diagnosis and intervention are crucial to prevent complications such as bleeding, seizures, or neurologic deficits associated with AVMs.¹

To the Editor:

Historically, commonly available antifungal medications have been effective for treating dermatophytosis (tinea). However, recent tinea outbreaks caused by Trichophyton indotineae—a dermatophyte often resistant to terbinafine and sometimes to other antifungals—have been reported in South Asia, Europe, the Middle East, Southeast Asia, and Australia.^1-5

Three confirmed cases of T indotineae dermatophytosis in the United States were reported in 2023 in New York^3,6; a fourth confirmed case was reported in 2024 in Pennsylvania.⁷ Post hoc laboratory testing of fungal isolates in New York in 2022 and 2023 identified an additional 11 cases.⁸ We present a case of extensive multidrug-resistant tinea caused by T indotineae in a man in California.

An otherwise healthy 65-year-old man who had traveled to Europe in the past 3 months presented to his primary care physician with a widespread pruritic rash (Figure 1). He was treated with 2 weeks of oral terbinafine 250 mg/d and topical medicines, including clotrimazole cream 1%, fluocinonide ointment 0.05%, and clobetasol ointment 0.05% without improvement. Subsequently, 2 weeks of oral griseofulvin microsize 500 mg/d also proved ineffective. An antibody test was negative for HIV. His hemoglobin A_1c was 6.2% (reference range, ≤5.6%). The patient was referred to dermatology.

Erythematous plaques—many scaly throughout and some annular with central clearing—were present on the arms, legs, and torso as well as in the groin. Honey crust was present on some plaques on the leg. A potassium hydroxide preparation showed abundant fungal hyphae. Material for fungal and bacterial cultures was collected. The patient was treated again with oral terbinafine 250 mg/d, an oral prednisone taper starting at 60 mg/d for a presumed id reaction, and various oral antihistamines for pruritus; all were ineffective. A bacterial culture showed only mixed skin flora. Oral fluconazole 200 mg/d was prescribed. A skin biopsy specimen showed compact orthokeratosis and parakeratosis of the stratum corneum with few neutrophils and focal pustule formation (Figure 2). Superficial perivascular inflammation, including lymphocytes, histiocytes, and few neutrophils, was present. A periodic acid–Schiff stain showed fungal hyphae in the stratum corneum and a hair follicle (Figure 3). After approximately 2 weeks, mold was identified in the fungal culture. Approximately 2 weeks thereafter, the organism was reported as Trichophyton species.

stuthitospislechethislouutheshotresamawropephispujecruthejahocrekegotropimuuucrewreciswegosuuecomopruclathestosheprelokaphedeuesalisapegitritrespepukemophucreclushithurulodriwawresitrohobolotricuseclimebophophakusw

clathogicropriuovamiwrishuwruprokiprasleueslolouitrasiculouiw

kisewregauuphidrathuthispebacristawiphutospuspacraswujumawowrifrubretebeswitruwitakagotrauotrupucakudufrohulislebupihislusuhoc

Acknowledgments—Jeremy Gold, MD; Dallas J. Smith, PharmD; and Shawn Lockhart, PhD, all of the Centers for Disease Control and Prevention, Mycotic Diseases Branch (Atlanta, Georgia), provided helpful comments to the authors in preparing the manuscript of this article.

To the Editor:

Historically, commonly available antifungal medications have been effective for treating dermatophytosis (tinea). However, recent tinea outbreaks caused by Trichophyton indotineae—a dermatophyte often resistant to terbinafine and sometimes to other antifungals—have been reported in South Asia, Europe, the Middle East, Southeast Asia, and Australia.^1-5

Three confirmed cases of T indotineae dermatophytosis in the United States were reported in 2023 in New York^3,6; a fourth confirmed case was reported in 2024 in Pennsylvania.⁷ Post hoc laboratory testing of fungal isolates in New York in 2022 and 2023 identified an additional 11 cases.⁸ We present a case of extensive multidrug-resistant tinea caused by T indotineae in a man in California.

An otherwise healthy 65-year-old man who had traveled to Europe in the past 3 months presented to his primary care physician with a widespread pruritic rash (Figure 1). He was treated with 2 weeks of oral terbinafine 250 mg/d and topical medicines, including clotrimazole cream 1%, fluocinonide ointment 0.05%, and clobetasol ointment 0.05% without improvement. Subsequently, 2 weeks of oral griseofulvin microsize 500 mg/d also proved ineffective. An antibody test was negative for HIV. His hemoglobin A_1c was 6.2% (reference range, ≤5.6%). The patient was referred to dermatology.

Erythematous plaques—many scaly throughout and some annular with central clearing—were present on the arms, legs, and torso as well as in the groin. Honey crust was present on some plaques on the leg. A potassium hydroxide preparation showed abundant fungal hyphae. Material for fungal and bacterial cultures was collected. The patient was treated again with oral terbinafine 250 mg/d, an oral prednisone taper starting at 60 mg/d for a presumed id reaction, and various oral antihistamines for pruritus; all were ineffective. A bacterial culture showed only mixed skin flora. Oral fluconazole 200 mg/d was prescribed. A skin biopsy specimen showed compact orthokeratosis and parakeratosis of the stratum corneum with few neutrophils and focal pustule formation (Figure 2). Superficial perivascular inflammation, including lymphocytes, histiocytes, and few neutrophils, was present. A periodic acid–Schiff stain showed fungal hyphae in the stratum corneum and a hair follicle (Figure 3). After approximately 2 weeks, mold was identified in the fungal culture. Approximately 2 weeks thereafter, the organism was reported as Trichophyton species.

stuthitospislechethislouutheshotresamawropephispujecruthejahocrekegotropimuuucrewreciswegosuuecomopruclathestosheprelokaphedeuesalisapegitritrespepukemophucreclushithurulodriwawresitrohobolotricuseclimebophophakusw

clathogicropriuovamiwrishuwruprokiprasleueslolouitrasiculouiw

kisewregauuphidrathuthispebacristawiphutospuspacraswujumawowrifrubretebeswitruwitakagotrauotrupucakudufrohulislebupihislusuhoc

Acknowledgments—Jeremy Gold, MD; Dallas J. Smith, PharmD; and Shawn Lockhart, PhD, all of the Centers for Disease Control and Prevention, Mycotic Diseases Branch (Atlanta, Georgia), provided helpful comments to the authors in preparing the manuscript of this article.

To the Editor:

Historically, commonly available antifungal medications have been effective for treating dermatophytosis (tinea). However, recent tinea outbreaks caused by Trichophyton indotineae—a dermatophyte often resistant to terbinafine and sometimes to other antifungals—have been reported in South Asia, Europe, the Middle East, Southeast Asia, and Australia.^1-5

Three confirmed cases of T indotineae dermatophytosis in the United States were reported in 2023 in New York^3,6; a fourth confirmed case was reported in 2024 in Pennsylvania.⁷ Post hoc laboratory testing of fungal isolates in New York in 2022 and 2023 identified an additional 11 cases.⁸ We present a case of extensive multidrug-resistant tinea caused by T indotineae in a man in California.

An otherwise healthy 65-year-old man who had traveled to Europe in the past 3 months presented to his primary care physician with a widespread pruritic rash (Figure 1). He was treated with 2 weeks of oral terbinafine 250 mg/d and topical medicines, including clotrimazole cream 1%, fluocinonide ointment 0.05%, and clobetasol ointment 0.05% without improvement. Subsequently, 2 weeks of oral griseofulvin microsize 500 mg/d also proved ineffective. An antibody test was negative for HIV. His hemoglobin A_1c was 6.2% (reference range, ≤5.6%). The patient was referred to dermatology.

Erythematous plaques—many scaly throughout and some annular with central clearing—were present on the arms, legs, and torso as well as in the groin. Honey crust was present on some plaques on the leg. A potassium hydroxide preparation showed abundant fungal hyphae. Material for fungal and bacterial cultures was collected. The patient was treated again with oral terbinafine 250 mg/d, an oral prednisone taper starting at 60 mg/d for a presumed id reaction, and various oral antihistamines for pruritus; all were ineffective. A bacterial culture showed only mixed skin flora. Oral fluconazole 200 mg/d was prescribed. A skin biopsy specimen showed compact orthokeratosis and parakeratosis of the stratum corneum with few neutrophils and focal pustule formation (Figure 2). Superficial perivascular inflammation, including lymphocytes, histiocytes, and few neutrophils, was present. A periodic acid–Schiff stain showed fungal hyphae in the stratum corneum and a hair follicle (Figure 3). After approximately 2 weeks, mold was identified in the fungal culture. Approximately 2 weeks thereafter, the organism was reported as Trichophyton species.

stuthitospislechethislouutheshotresamawropephispujecruthejahocrekegotropimuuucrewreciswegosuuecomopruclathestosheprelokaphedeuesalisapegitritrespepukemophucreclushithurulodriwawresitrohobolotricuseclimebophophakusw

clathogicropriuovamiwrishuwruprokiprasleueslolouitrasiculouiw

kisewregauuphidrathuthispebacristawiphutospuspacraswujumawowrifrubretebeswitruwitakagotrauotrupucakudufrohulislebupihislusuhoc

Acknowledgments—Jeremy Gold, MD; Dallas J. Smith, PharmD; and Shawn Lockhart, PhD, all of the Centers for Disease Control and Prevention, Mycotic Diseases Branch (Atlanta, Georgia), provided helpful comments to the authors in preparing the manuscript of this article.

Dermatology residents interact with trainees of various levels throughout the workday—from undergraduate or even high school students to postgraduate fellows. Depending on the institution’s training program, residents may have responsibilities to teach through lecture series such as Grand Rounds and didactics. Therefore, it is an integral part of resident training to become educators in addition to being learners; however, formal pedagogy education is rare in dermatology programs. ^1,2 Herein, I discuss several techniques that residents can apply to their practice to cultivate ideal learning environments and outcomes for trainees.

Creating Effective Teaching and Learning Experiences

Planning to teach can be as important as teaching itself. Developing learning objectives can help to create effective teaching and learning experiences. Learning objectives should be specific, time bound, attainable, and learner centered (Table 1). It is recommended that residents aim for no more than 4 objectives per hour of learning.³ By creating clear learning objectives, residents can make connections between the content and any assessments. Bloom’s taxonomy of cognitive learning objectives gives guidance on action verbs to use in writing learning ­objectives depending on the cognitive process being tested (Table 2).⁴

Creating a Safe Educational Environment

Psychological safety is the belief that a learning environment is a safe place in which to take risks.⁵ A clinical learning environment that is psychologically safe can support trainee well-being and learning. Cultivating a safe educational environment may include addressing microaggressions and bias in the clinical workplace. Table 3 provides examples of statements using the 6 Ds, which can be used to mitigate these issues.⁶ The first 4—direct, distract, delegate, and defer—represent ways to respond to racism, microaggressions, and bias, and the last 2—­display discomfort and debrief—are responses that may be ­utilized in any problematic incident. Residents can play an important supportive role in scenarios where learners are faced with an incident that may not be regarded as psychologically safe. This is especially true if the learner is at a lower training level than the dermatology resident. We all play a role in creating a safe workplace for our teams.

rihostutrimubrunadrufristaspokeshithimidahatuswufrobebrakeliceretacasleguketricuvewragupasuprotadrec

sucrorothikelocrulacrimusluslatibiwrekacruthadribouagiswefronitrumuberorehediveruclodrespeslasluchonagopisochotricletrugotruchasiprufriu

phathosuproclespijocl

Teaching in the Clinic and Hospital

There are multiple challenges to teaching in both inpatient and outpatient environments, including limited space and time; thus, more informal teaching methods are common. For example, in an outpatient dermatology clinic, the patient schedule can become a “table of contents” of potential teaching and learning opportunities. This technique is called the focused half day.^3,7 By reviewing the clinic schedule, students can focus on a specific area of interest or theme throughout the course of the day.³

Priming and framing are other focused techniques that work well in both outpatient and inpatient settings.^3,8,9 Priming means alerting the trainee to upcoming learning objective(s) and focusing their attention on what to observe or do during a shared visit with a patient. Framing—instructing learners to collect information that is relevant to the diagnosis and treatment—allows trainees to help move patient care forward while the resident attends to other patients.³

Modeling involves describing a thought process out loud for a learner^3,10; for example, prior to starting a patient encounter, a dermatology resident may clearly state the goal of a patient conversation to the learner, describe their thought process about the topic, summarize the important points, and ask the learner if they have any questions about what was just said. Using this technique, learners may have a better understanding of why and how to go about conducting a patient encounter after the resident models one for them.

Effectively Integrating Visual Media and Presentations

Research supported by the cognitive load theory and cognitive theory of multimedia learning has led to the assertion-evidence approach for creating presentation slides that are built around messages, not topics, and messages are supported with visuals, not bullets.^3,11,12 For example, slides should be constructed with 1- to 2-line assertion statements as titles and relevant illustrations or figures as supporting evidence to enhance visual memory.³

Written text on presentation slides often is redundant with spoken narration and also decreases learning because of cognitive load. Busy background colors and/or designs consume working memory and also can be detrimental to learning. Limiting these common distractors in a presentation makes for more effective delivery and retention of knowledge.³

Final Thoughts

There are multiple avenues for teaching as a resident and not all techniques may be applicable depending on the clinical or academic scenario. This column provides a starting point for residents to augment their pedagogical skills, particularly because formal teaching on pedagogy is lacking in medical education.

Dermatology residents interact with trainees of various levels throughout the workday—from undergraduate or even high school students to postgraduate fellows. Depending on the institution’s training program, residents may have responsibilities to teach through lecture series such as Grand Rounds and didactics. Therefore, it is an integral part of resident training to become educators in addition to being learners; however, formal pedagogy education is rare in dermatology programs. ^1,2 Herein, I discuss several techniques that residents can apply to their practice to cultivate ideal learning environments and outcomes for trainees.

Creating Effective Teaching and Learning Experiences

Planning to teach can be as important as teaching itself. Developing learning objectives can help to create effective teaching and learning experiences. Learning objectives should be specific, time bound, attainable, and learner centered (Table 1). It is recommended that residents aim for no more than 4 objectives per hour of learning.³ By creating clear learning objectives, residents can make connections between the content and any assessments. Bloom’s taxonomy of cognitive learning objectives gives guidance on action verbs to use in writing learning ­objectives depending on the cognitive process being tested (Table 2).⁴

Creating a Safe Educational Environment

Psychological safety is the belief that a learning environment is a safe place in which to take risks.⁵ A clinical learning environment that is psychologically safe can support trainee well-being and learning. Cultivating a safe educational environment may include addressing microaggressions and bias in the clinical workplace. Table 3 provides examples of statements using the 6 Ds, which can be used to mitigate these issues.⁶ The first 4—direct, distract, delegate, and defer—represent ways to respond to racism, microaggressions, and bias, and the last 2—­display discomfort and debrief—are responses that may be ­utilized in any problematic incident. Residents can play an important supportive role in scenarios where learners are faced with an incident that may not be regarded as psychologically safe. This is especially true if the learner is at a lower training level than the dermatology resident. We all play a role in creating a safe workplace for our teams.

rihostutrimubrunadrufristaspokeshithimidahatuswufrobebrakeliceretacasleguketricuvewragupasuprotadrec

sucrorothikelocrulacrimusluslatibiwrekacruthadribouagiswefronitrumuberorehediveruclodrespeslasluchonagopisochotricletrugotruchasiprufriu

phathosuproclespijocl

Teaching in the Clinic and Hospital

There are multiple challenges to teaching in both inpatient and outpatient environments, including limited space and time; thus, more informal teaching methods are common. For example, in an outpatient dermatology clinic, the patient schedule can become a “table of contents” of potential teaching and learning opportunities. This technique is called the focused half day.^3,7 By reviewing the clinic schedule, students can focus on a specific area of interest or theme throughout the course of the day.³

Priming and framing are other focused techniques that work well in both outpatient and inpatient settings.^3,8,9 Priming means alerting the trainee to upcoming learning objective(s) and focusing their attention on what to observe or do during a shared visit with a patient. Framing—instructing learners to collect information that is relevant to the diagnosis and treatment—allows trainees to help move patient care forward while the resident attends to other patients.³

Modeling involves describing a thought process out loud for a learner^3,10; for example, prior to starting a patient encounter, a dermatology resident may clearly state the goal of a patient conversation to the learner, describe their thought process about the topic, summarize the important points, and ask the learner if they have any questions about what was just said. Using this technique, learners may have a better understanding of why and how to go about conducting a patient encounter after the resident models one for them.

Effectively Integrating Visual Media and Presentations

Research supported by the cognitive load theory and cognitive theory of multimedia learning has led to the assertion-evidence approach for creating presentation slides that are built around messages, not topics, and messages are supported with visuals, not bullets.^3,11,12 For example, slides should be constructed with 1- to 2-line assertion statements as titles and relevant illustrations or figures as supporting evidence to enhance visual memory.³

Written text on presentation slides often is redundant with spoken narration and also decreases learning because of cognitive load. Busy background colors and/or designs consume working memory and also can be detrimental to learning. Limiting these common distractors in a presentation makes for more effective delivery and retention of knowledge.³

Final Thoughts

There are multiple avenues for teaching as a resident and not all techniques may be applicable depending on the clinical or academic scenario. This column provides a starting point for residents to augment their pedagogical skills, particularly because formal teaching on pedagogy is lacking in medical education.

Dermatology residents interact with trainees of various levels throughout the workday—from undergraduate or even high school students to postgraduate fellows. Depending on the institution’s training program, residents may have responsibilities to teach through lecture series such as Grand Rounds and didactics. Therefore, it is an integral part of resident training to become educators in addition to being learners; however, formal pedagogy education is rare in dermatology programs. ^1,2 Herein, I discuss several techniques that residents can apply to their practice to cultivate ideal learning environments and outcomes for trainees.

Creating Effective Teaching and Learning Experiences

Planning to teach can be as important as teaching itself. Developing learning objectives can help to create effective teaching and learning experiences. Learning objectives should be specific, time bound, attainable, and learner centered (Table 1). It is recommended that residents aim for no more than 4 objectives per hour of learning.³ By creating clear learning objectives, residents can make connections between the content and any assessments. Bloom’s taxonomy of cognitive learning objectives gives guidance on action verbs to use in writing learning ­objectives depending on the cognitive process being tested (Table 2).⁴

Creating a Safe Educational Environment

Psychological safety is the belief that a learning environment is a safe place in which to take risks.⁵ A clinical learning environment that is psychologically safe can support trainee well-being and learning. Cultivating a safe educational environment may include addressing microaggressions and bias in the clinical workplace. Table 3 provides examples of statements using the 6 Ds, which can be used to mitigate these issues.⁶ The first 4—direct, distract, delegate, and defer—represent ways to respond to racism, microaggressions, and bias, and the last 2—­display discomfort and debrief—are responses that may be ­utilized in any problematic incident. Residents can play an important supportive role in scenarios where learners are faced with an incident that may not be regarded as psychologically safe. This is especially true if the learner is at a lower training level than the dermatology resident. We all play a role in creating a safe workplace for our teams.

rihostutrimubrunadrufristaspokeshithimidahatuswufrobebrakeliceretacasleguketricuvewragupasuprotadrec

sucrorothikelocrulacrimusluslatibiwrekacruthadribouagiswefronitrumuberorehediveruclodrespeslasluchonagopisochotricletrugotruchasiprufriu

phathosuproclespijocl

Teaching in the Clinic and Hospital

There are multiple challenges to teaching in both inpatient and outpatient environments, including limited space and time; thus, more informal teaching methods are common. For example, in an outpatient dermatology clinic, the patient schedule can become a “table of contents” of potential teaching and learning opportunities. This technique is called the focused half day.^3,7 By reviewing the clinic schedule, students can focus on a specific area of interest or theme throughout the course of the day.³

Priming and framing are other focused techniques that work well in both outpatient and inpatient settings.^3,8,9 Priming means alerting the trainee to upcoming learning objective(s) and focusing their attention on what to observe or do during a shared visit with a patient. Framing—instructing learners to collect information that is relevant to the diagnosis and treatment—allows trainees to help move patient care forward while the resident attends to other patients.³

Modeling involves describing a thought process out loud for a learner^3,10; for example, prior to starting a patient encounter, a dermatology resident may clearly state the goal of a patient conversation to the learner, describe their thought process about the topic, summarize the important points, and ask the learner if they have any questions about what was just said. Using this technique, learners may have a better understanding of why and how to go about conducting a patient encounter after the resident models one for them.

Effectively Integrating Visual Media and Presentations

Research supported by the cognitive load theory and cognitive theory of multimedia learning has led to the assertion-evidence approach for creating presentation slides that are built around messages, not topics, and messages are supported with visuals, not bullets.^3,11,12 For example, slides should be constructed with 1- to 2-line assertion statements as titles and relevant illustrations or figures as supporting evidence to enhance visual memory.³

Written text on presentation slides often is redundant with spoken narration and also decreases learning because of cognitive load. Busy background colors and/or designs consume working memory and also can be detrimental to learning. Limiting these common distractors in a presentation makes for more effective delivery and retention of knowledge.³

Final Thoughts

There are multiple avenues for teaching as a resident and not all techniques may be applicable depending on the clinical or academic scenario. This column provides a starting point for residents to augment their pedagogical skills, particularly because formal teaching on pedagogy is lacking in medical education.

To the Editor:

Cardiac rhabdomyomas are benign hamartomas that are common in patients with tuberous sclerosis complex (TSC).¹ We describe a patient who presented with large infantile hemangiomas (IHs) and hypopigmented macules, which prompted further testing that eventually showed concomitant multiple cardiac rhabdomyomas in the context of TSC.

A 5-week-old girl—who was born at 38 weeks and 3 days’ gestation via uncomplicated vaginal delivery—was referred to our pediatric dermatology clinic for evaluation of multiple erythematous lesions on the scalp and left buttock that were first noticed 2 weeks prior to presentation. There was a family history of seizures in the patient’s mother. The patient’s older brother did not have similar symptoms.

Physical examination revealed 2 nonulcerating erythematous nodules on the middle and posterior left vertex scalp that measured 2.5×2 cm (Figure 1A) as well as 1 bright red plaque on the left buttock (Figure 1B). Five hypopigmented macules, ranging from 5 mm to 1.5 cm in diameter, also were detected on the left thorax (Figure 2A) as well as the middle and lower back (Figure 2B). These findings, along with the history of seizures in the patient’s mother, prompted further evaluation of the family history, which uncovered TSC in the patient’s mother, maternal aunt, and maternal grandmother.

The large IHs on the scalp did not pose concerns for potential functional impairment but were still considered high risk for permanent alopecia based on clinical practice guidelines for the management of IH.² Treatment with oral propranolol was recommended; however, because of a strong suspicion of TSC due to the presence of 5 hypopigmented macules measuring more than 5 mm in diameter (≥3 hypopigmented macules of ≥5 mm is one of the major criterion for TSC), the patient was referred to cardiology prior to initiation of propranolol.

Echocardiography revealed 3 intracardiac masses measuring 4 to 5 mm in diameter in the left ventricle (LV), along the interventricular septum and the LV posterior wall. These masses were consistent with rhabdomyomas (Figure 3)—a major criterion for TSC—which had not been detected by prenatal ultrasonography. No obstruction to LV inflow or outflow was observed. Additionally, no arrhythmias were detected on electrocardiography.

The patient was cleared for propranolol, which was slowly uptitrated to 2 mg/kg/d. She completed the course without adverse effects. The treatment of IH was successful with substantial reduction in size over the following months until clearance. She also was referred to neurology for magnetic resonance imaging of the brain, which showed a 3-mm subependymal nodule in the lateral right ventricle, another major feature of TSC.

prosluchishauivituspugunepraphuphusleslopegestilod

Cardiac rhabdomyomas are benign hamartomas that affect as many as 80% of patients with TSC¹ and are primarily localized in the ventricles. Although cardiac rhabdomyomas usually regress over time, they can compromise ventricular function or valvular function, or both, and result in outflow obstruction, arrhythmias, and Wolff- Parkinson-White syndrome.³ Surgical resection may be needed in patients whose condition is refractory to medical management for heart failure.

The pathophysiologic mechanism behind the natural involution of cardiac rhabdomyomas has not been fully elucidated. It has been hypothesized that these masses stem from the inability of rhabdomyoma cells to divide after birth due to their embryonic myocyte derivation.⁴

According to the TSC diagnostic criteria from the Tuberous Sclerosis Complex International Consensus Group, at least 2 major features or 1 major and 2 minor features are required to make a definitive diagnosis of TSC. Cutaneous signs represent more than one-third of major features of TSC; almost all patients with TSC have skin findings.⁵

Identification of pathogenic mutations in either TSC¹ (on chromosome 9q34.3, encoding for hamartin) or TSC² (on chromosome 16p13.3, encoding for tuberin), resulting in constitutive activation of mammalian target of rapamycin and subsequent increased cell growth, is sufficient for a definitive diagnosis of TSC. However, mutations cannot be identified by conventional genetic testing in as many as one-quarter of patients with TSC; therefore, a negative result does not exclude TSC if the patient meets clinical diagnostic criteria.

cothiswugedetrilovuwushadrikaswunaspudriwotrucrigicladrudruguhogaswihoclocluvechebraclipobivijesawrokuwutamefredodrechudeuefroslosecroclihematrugalacliwislebribriswoneshokevustikaspocladuslunoslaswifrowropiwuswuphucuwepiuav

badohachoprochivoclinowodrihefrikejetrecralajawakenuchoswenivubriclorucrichepotedrathocihowrumucofruloslucajepowiwroth

Although a cardiology workup is indicated prior to initiating propranolol in the presence of possible cardiac rhabdomyomas, most of those lesions are hemodynamically stable and do not require treatment. There also is no contraindication for β-blocker therapy. In fact, propranolol has been reported as a successful treatment in rhabdomyoma-associated arrhythmias in children.⁶ Notably, obstructive cardiac rhabdomyomas have been successfully treated with mammalian target of rapamycin inhibitors, such as sirolimus⁷ and everolimus.⁸

Baseline cardiology screening with echocardiography prior to initiating propranolol for treatment of IH is not routinely indicated in babies with uncomplicated IH. However, in a patient with TSC, cardiology screening is necessary to rule out rhabdomyomas with associated arrhythmias or obstructed blood flow, or both, prior to initiating treatment.

We presented a case of concomitant IH and TSC in a patient with cardiac rhabdomyomas. The manifestation of large IHs in our patient prompted further testing that revealed multiple cardiac rhabdomyomas in the context of TSC. It is imperative for cardiologists, cardiac surgeons, and dermatologists to be familiar with the TSC diagnostic criteria so that they can reach a prompt diagnosis and make appropriate referrals for further evaluation of cardiac, neurologic, and ophthalmologic signs.

To the Editor:

Cardiac rhabdomyomas are benign hamartomas that are common in patients with tuberous sclerosis complex (TSC).¹ We describe a patient who presented with large infantile hemangiomas (IHs) and hypopigmented macules, which prompted further testing that eventually showed concomitant multiple cardiac rhabdomyomas in the context of TSC.

A 5-week-old girl—who was born at 38 weeks and 3 days’ gestation via uncomplicated vaginal delivery—was referred to our pediatric dermatology clinic for evaluation of multiple erythematous lesions on the scalp and left buttock that were first noticed 2 weeks prior to presentation. There was a family history of seizures in the patient’s mother. The patient’s older brother did not have similar symptoms.

Physical examination revealed 2 nonulcerating erythematous nodules on the middle and posterior left vertex scalp that measured 2.5×2 cm (Figure 1A) as well as 1 bright red plaque on the left buttock (Figure 1B). Five hypopigmented macules, ranging from 5 mm to 1.5 cm in diameter, also were detected on the left thorax (Figure 2A) as well as the middle and lower back (Figure 2B). These findings, along with the history of seizures in the patient’s mother, prompted further evaluation of the family history, which uncovered TSC in the patient’s mother, maternal aunt, and maternal grandmother.

The large IHs on the scalp did not pose concerns for potential functional impairment but were still considered high risk for permanent alopecia based on clinical practice guidelines for the management of IH.² Treatment with oral propranolol was recommended; however, because of a strong suspicion of TSC due to the presence of 5 hypopigmented macules measuring more than 5 mm in diameter (≥3 hypopigmented macules of ≥5 mm is one of the major criterion for TSC), the patient was referred to cardiology prior to initiation of propranolol.

Echocardiography revealed 3 intracardiac masses measuring 4 to 5 mm in diameter in the left ventricle (LV), along the interventricular septum and the LV posterior wall. These masses were consistent with rhabdomyomas (Figure 3)—a major criterion for TSC—which had not been detected by prenatal ultrasonography. No obstruction to LV inflow or outflow was observed. Additionally, no arrhythmias were detected on electrocardiography.

The patient was cleared for propranolol, which was slowly uptitrated to 2 mg/kg/d. She completed the course without adverse effects. The treatment of IH was successful with substantial reduction in size over the following months until clearance. She also was referred to neurology for magnetic resonance imaging of the brain, which showed a 3-mm subependymal nodule in the lateral right ventricle, another major feature of TSC.

prosluchishauivituspugunepraphuphusleslopegestilod

Cardiac rhabdomyomas are benign hamartomas that affect as many as 80% of patients with TSC¹ and are primarily localized in the ventricles. Although cardiac rhabdomyomas usually regress over time, they can compromise ventricular function or valvular function, or both, and result in outflow obstruction, arrhythmias, and Wolff- Parkinson-White syndrome.³ Surgical resection may be needed in patients whose condition is refractory to medical management for heart failure.

The pathophysiologic mechanism behind the natural involution of cardiac rhabdomyomas has not been fully elucidated. It has been hypothesized that these masses stem from the inability of rhabdomyoma cells to divide after birth due to their embryonic myocyte derivation.⁴

According to the TSC diagnostic criteria from the Tuberous Sclerosis Complex International Consensus Group, at least 2 major features or 1 major and 2 minor features are required to make a definitive diagnosis of TSC. Cutaneous signs represent more than one-third of major features of TSC; almost all patients with TSC have skin findings.⁵

Identification of pathogenic mutations in either TSC¹ (on chromosome 9q34.3, encoding for hamartin) or TSC² (on chromosome 16p13.3, encoding for tuberin), resulting in constitutive activation of mammalian target of rapamycin and subsequent increased cell growth, is sufficient for a definitive diagnosis of TSC. However, mutations cannot be identified by conventional genetic testing in as many as one-quarter of patients with TSC; therefore, a negative result does not exclude TSC if the patient meets clinical diagnostic criteria.

cothiswugedetrilovuwushadrikaswunaspudriwotrucrigicladrudruguhogaswihoclocluvechebraclipobivijesawrokuwutamefredodrechudeuefroslosecroclihematrugalacliwislebribriswoneshokevustikaspocladuslunoslaswifrowropiwuswuphucuwepiuav

badohachoprochivoclinowodrihefrikejetrecralajawakenuchoswenivubriclorucrichepotedrathocihowrumucofruloslucajepowiwroth

Although a cardiology workup is indicated prior to initiating propranolol in the presence of possible cardiac rhabdomyomas, most of those lesions are hemodynamically stable and do not require treatment. There also is no contraindication for β-blocker therapy. In fact, propranolol has been reported as a successful treatment in rhabdomyoma-associated arrhythmias in children.⁶ Notably, obstructive cardiac rhabdomyomas have been successfully treated with mammalian target of rapamycin inhibitors, such as sirolimus⁷ and everolimus.⁸

Baseline cardiology screening with echocardiography prior to initiating propranolol for treatment of IH is not routinely indicated in babies with uncomplicated IH. However, in a patient with TSC, cardiology screening is necessary to rule out rhabdomyomas with associated arrhythmias or obstructed blood flow, or both, prior to initiating treatment.

We presented a case of concomitant IH and TSC in a patient with cardiac rhabdomyomas. The manifestation of large IHs in our patient prompted further testing that revealed multiple cardiac rhabdomyomas in the context of TSC. It is imperative for cardiologists, cardiac surgeons, and dermatologists to be familiar with the TSC diagnostic criteria so that they can reach a prompt diagnosis and make appropriate referrals for further evaluation of cardiac, neurologic, and ophthalmologic signs.

To the Editor:

Cardiac rhabdomyomas are benign hamartomas that are common in patients with tuberous sclerosis complex (TSC).¹ We describe a patient who presented with large infantile hemangiomas (IHs) and hypopigmented macules, which prompted further testing that eventually showed concomitant multiple cardiac rhabdomyomas in the context of TSC.

A 5-week-old girl—who was born at 38 weeks and 3 days’ gestation via uncomplicated vaginal delivery—was referred to our pediatric dermatology clinic for evaluation of multiple erythematous lesions on the scalp and left buttock that were first noticed 2 weeks prior to presentation. There was a family history of seizures in the patient’s mother. The patient’s older brother did not have similar symptoms.

Physical examination revealed 2 nonulcerating erythematous nodules on the middle and posterior left vertex scalp that measured 2.5×2 cm (Figure 1A) as well as 1 bright red plaque on the left buttock (Figure 1B). Five hypopigmented macules, ranging from 5 mm to 1.5 cm in diameter, also were detected on the left thorax (Figure 2A) as well as the middle and lower back (Figure 2B). These findings, along with the history of seizures in the patient’s mother, prompted further evaluation of the family history, which uncovered TSC in the patient’s mother, maternal aunt, and maternal grandmother.

The large IHs on the scalp did not pose concerns for potential functional impairment but were still considered high risk for permanent alopecia based on clinical practice guidelines for the management of IH.² Treatment with oral propranolol was recommended; however, because of a strong suspicion of TSC due to the presence of 5 hypopigmented macules measuring more than 5 mm in diameter (≥3 hypopigmented macules of ≥5 mm is one of the major criterion for TSC), the patient was referred to cardiology prior to initiation of propranolol.

Echocardiography revealed 3 intracardiac masses measuring 4 to 5 mm in diameter in the left ventricle (LV), along the interventricular septum and the LV posterior wall. These masses were consistent with rhabdomyomas (Figure 3)—a major criterion for TSC—which had not been detected by prenatal ultrasonography. No obstruction to LV inflow or outflow was observed. Additionally, no arrhythmias were detected on electrocardiography.

The patient was cleared for propranolol, which was slowly uptitrated to 2 mg/kg/d. She completed the course without adverse effects. The treatment of IH was successful with substantial reduction in size over the following months until clearance. She also was referred to neurology for magnetic resonance imaging of the brain, which showed a 3-mm subependymal nodule in the lateral right ventricle, another major feature of TSC.

prosluchishauivituspugunepraphuphusleslopegestilod

Cardiac rhabdomyomas are benign hamartomas that affect as many as 80% of patients with TSC¹ and are primarily localized in the ventricles. Although cardiac rhabdomyomas usually regress over time, they can compromise ventricular function or valvular function, or both, and result in outflow obstruction, arrhythmias, and Wolff- Parkinson-White syndrome.³ Surgical resection may be needed in patients whose condition is refractory to medical management for heart failure.

The pathophysiologic mechanism behind the natural involution of cardiac rhabdomyomas has not been fully elucidated. It has been hypothesized that these masses stem from the inability of rhabdomyoma cells to divide after birth due to their embryonic myocyte derivation.⁴

According to the TSC diagnostic criteria from the Tuberous Sclerosis Complex International Consensus Group, at least 2 major features or 1 major and 2 minor features are required to make a definitive diagnosis of TSC. Cutaneous signs represent more than one-third of major features of TSC; almost all patients with TSC have skin findings.⁵

Identification of pathogenic mutations in either TSC¹ (on chromosome 9q34.3, encoding for hamartin) or TSC² (on chromosome 16p13.3, encoding for tuberin), resulting in constitutive activation of mammalian target of rapamycin and subsequent increased cell growth, is sufficient for a definitive diagnosis of TSC. However, mutations cannot be identified by conventional genetic testing in as many as one-quarter of patients with TSC; therefore, a negative result does not exclude TSC if the patient meets clinical diagnostic criteria.

cothiswugedetrilovuwushadrikaswunaspudriwotrucrigicladrudruguhogaswihoclocluvechebraclipobivijesawrokuwutamefredodrechudeuefroslosecroclihematrugalacliwislebribriswoneshokevustikaspocladuslunoslaswifrowropiwuswuphucuwepiuav

badohachoprochivoclinowodrihefrikejetrecralajawakenuchoswenivubriclorucrichepotedrathocihowrumucofruloslucajepowiwroth

Although a cardiology workup is indicated prior to initiating propranolol in the presence of possible cardiac rhabdomyomas, most of those lesions are hemodynamically stable and do not require treatment. There also is no contraindication for β-blocker therapy. In fact, propranolol has been reported as a successful treatment in rhabdomyoma-associated arrhythmias in children.⁶ Notably, obstructive cardiac rhabdomyomas have been successfully treated with mammalian target of rapamycin inhibitors, such as sirolimus⁷ and everolimus.⁸

Baseline cardiology screening with echocardiography prior to initiating propranolol for treatment of IH is not routinely indicated in babies with uncomplicated IH. However, in a patient with TSC, cardiology screening is necessary to rule out rhabdomyomas with associated arrhythmias or obstructed blood flow, or both, prior to initiating treatment.

We presented a case of concomitant IH and TSC in a patient with cardiac rhabdomyomas. The manifestation of large IHs in our patient prompted further testing that revealed multiple cardiac rhabdomyomas in the context of TSC. It is imperative for cardiologists, cardiac surgeons, and dermatologists to be familiar with the TSC diagnostic criteria so that they can reach a prompt diagnosis and make appropriate referrals for further evaluation of cardiac, neurologic, and ophthalmologic signs.

The Diagnosis: Trichodysplasia Spinulosa

A diagnosis of trichodysplasia spinulosa (TS) was rendered based on the clinical presentation— diffuse folliculocentric keratotic papules with spicules and leonine facies—coinciding with cyclosporine initiation. Biopsy was deferred given the classic presentation. The patient applied cidofovir cream 1% daily to lesions on the face. She was prescribed leflunomide 10 mg daily, which was later increased to 20 mg daily, for polyarthritis associated with systemic lupus erythematosus (SLE). Her transplant physician increased her cyclosporine dosage from 50 mg twice daily to 75 mg each morning and 50 mg each evening due to rising creatinine and donor-specific antibodies from the renal transplant. The patient’s TS eruption mildly improved 3 months after the cyclosporine dose was increased. To treat persistent lesions, oral valganciclovir was started at 450 mg once daily and later reduced to every other day due to leukopenia. After 3 months of taking valganciclovir 450 mg every other day, the patient’s TS rash resolved.

Trichodysplasia spinulosa is a rare condition caused by TS-associated polyomavirus¹ that may arise in immunosuppressed patients, especially in solid organ transplant recipients.² It is characterized by spiculated and folliculocentric papules, mainly on the face,¹ and often is diagnosed clinically, but if the presentation is not classic, a skin biopsy can help to confirm the diagnosis. Because of its rarity, treatment options do not have well-established efficacy¹ but include reducing immunosuppression and using the antivirals cidofovir¹ or valganciclovir³ to treat the polyomavirus. Topical retinoids,³ photodynamic therapy, ⁴ and leflunomide⁵ also may be effective.

Although the typical approach to treating TS is to reduce immunosuppression, this was not an option for our patient, as she required increased immunosuppression for the treatment of active SLE. Leflunomide can be used for SLE, and in some reports it can be effective for BK viremia in kidney transplant recipients⁵ as well as for TS in solid organ transplant recipients.⁶ Our patient showed improvement of the TS, BK viremia, renal function, and SLE while taking leflunomide and valganciclovir.

The differential diagnosis includes keratosis pilaris, lichen nitidus, scleromyxedema, and trichostasis spinulosa. Keratosis pilaris is a benign skin disorder consisting of patches of keratotic papules with varying degrees of erythema and inflammation that are formed by dead keratinocytes plugging the hair follicles and often are seen on the extremities, face, and trunk.⁷ Our patient’s papules were flesh colored with no notable background erythema. Additionally, the presence of leonine facies was atypical for keratosis pilaris. Acids, steroids, and kinase inhibitors are the most frequently used treatments for keratosis pilaris.⁸

Lichen nitidus is a skin condition characterized by multiple shiny, dome-shaped, flesh-colored papules usually found on the flexor surfaces of the arms, anterior trunk, and genitalia. It is mostly asymptomatic, but patients may experience pruritus. Most cases occur in children and young adults, with no obvious racial or gender predilection. The diagnosis often is clinical, but biopsy shows downward enlargement of the epidermal rete ridges surrounding a focal inflammatory infiltrate, known as a ball-in-claw configuration.^9-11 Lichen nitidus spontaneously resolves within a few years without treatment. Our patient did have flesh-colored papules on the arms and chest; however, major involvement of the face is not typical in lichen nitidus. Additionally, fine white spicules would not be seen in lichen nitidus. For severe generalized lichen nitidus, treatment options include topical corticosteroids, topical calcineurin inhibitors, oral antihistamines, or UV light to decrease inflammation.^9-11

Scleromyxedema is a rare condition involving the deposition of mucinous material in the papillary dermis to cause the formation of infiltrative skin lesions.¹² It is thought that immunoglobulins and cytokines secreted by inflammatory cells lead to the synthesis of glycosaminoglycans, which then causes deposition of mucin in the dermis.¹³ The classic cutaneous features of scleromyxedema include waxy indurated papules and plaques with skin thickening throughout the entire body.¹² Our patient’s papules were not notably indurated and involved less than 50% of the total body surface area. An important diagnostic feature of scleromyxedema is monoclonal gammopathy, which our patient did not have. Intravenous immunoglobulin is the first-line treatment of scleromyxedema, and second-line treatments include systemic corticosteroids and thalidomide.¹⁴ Our patient also did not require treatment with intravenous immunoglobulin, as her rash improved with antiviral medication, which would not address the underlying inflammatory processes associated with scleromyxedema.

Trichostasis spinulosa is a rare hair follicle disorder consisting of dark, spiny, hyperkeratotic follicular papules that can be found on the extremities and face, especially the nose. The etiology is unknown, but risk factors include congenital dysplasia of hair follicles; exposure to UV light, dust, oil, or heat; chronic renal failure; Malassezia yeast; and Propionibacterium acnes. Adult women with darker skin types are most commonly affected by trichostasis spinulosa.^15,16 Our patient fit the epidemiologic demographic of trichostasis spinulosa, including a history of chronic renal failure. Her rash covered the face, nose, and arms; however, the papules were flesh colored, whereas trichostasis spinulosa would appear as black papules. Furthermore, yeast and bacterial infections have been identified as potential agents associated with trichostasis spinulosa; therefore, antiviral agents would be ineffective. Viable treatments for trichostasis spinulosa include emollients, topical keratolytic agents, retinoic acids, and lasers to remove abnormal hair follicles.^15,16

The Diagnosis: Trichodysplasia Spinulosa

A diagnosis of trichodysplasia spinulosa (TS) was rendered based on the clinical presentation— diffuse folliculocentric keratotic papules with spicules and leonine facies—coinciding with cyclosporine initiation. Biopsy was deferred given the classic presentation. The patient applied cidofovir cream 1% daily to lesions on the face. She was prescribed leflunomide 10 mg daily, which was later increased to 20 mg daily, for polyarthritis associated with systemic lupus erythematosus (SLE). Her transplant physician increased her cyclosporine dosage from 50 mg twice daily to 75 mg each morning and 50 mg each evening due to rising creatinine and donor-specific antibodies from the renal transplant. The patient’s TS eruption mildly improved 3 months after the cyclosporine dose was increased. To treat persistent lesions, oral valganciclovir was started at 450 mg once daily and later reduced to every other day due to leukopenia. After 3 months of taking valganciclovir 450 mg every other day, the patient’s TS rash resolved.

Trichodysplasia spinulosa is a rare condition caused by TS-associated polyomavirus¹ that may arise in immunosuppressed patients, especially in solid organ transplant recipients.² It is characterized by spiculated and folliculocentric papules, mainly on the face,¹ and often is diagnosed clinically, but if the presentation is not classic, a skin biopsy can help to confirm the diagnosis. Because of its rarity, treatment options do not have well-established efficacy¹ but include reducing immunosuppression and using the antivirals cidofovir¹ or valganciclovir³ to treat the polyomavirus. Topical retinoids,³ photodynamic therapy, ⁴ and leflunomide⁵ also may be effective.

Although the typical approach to treating TS is to reduce immunosuppression, this was not an option for our patient, as she required increased immunosuppression for the treatment of active SLE. Leflunomide can be used for SLE, and in some reports it can be effective for BK viremia in kidney transplant recipients⁵ as well as for TS in solid organ transplant recipients.⁶ Our patient showed improvement of the TS, BK viremia, renal function, and SLE while taking leflunomide and valganciclovir.

The differential diagnosis includes keratosis pilaris, lichen nitidus, scleromyxedema, and trichostasis spinulosa. Keratosis pilaris is a benign skin disorder consisting of patches of keratotic papules with varying degrees of erythema and inflammation that are formed by dead keratinocytes plugging the hair follicles and often are seen on the extremities, face, and trunk.⁷ Our patient’s papules were flesh colored with no notable background erythema. Additionally, the presence of leonine facies was atypical for keratosis pilaris. Acids, steroids, and kinase inhibitors are the most frequently used treatments for keratosis pilaris.⁸

Lichen nitidus is a skin condition characterized by multiple shiny, dome-shaped, flesh-colored papules usually found on the flexor surfaces of the arms, anterior trunk, and genitalia. It is mostly asymptomatic, but patients may experience pruritus. Most cases occur in children and young adults, with no obvious racial or gender predilection. The diagnosis often is clinical, but biopsy shows downward enlargement of the epidermal rete ridges surrounding a focal inflammatory infiltrate, known as a ball-in-claw configuration.^9-11 Lichen nitidus spontaneously resolves within a few years without treatment. Our patient did have flesh-colored papules on the arms and chest; however, major involvement of the face is not typical in lichen nitidus. Additionally, fine white spicules would not be seen in lichen nitidus. For severe generalized lichen nitidus, treatment options include topical corticosteroids, topical calcineurin inhibitors, oral antihistamines, or UV light to decrease inflammation.^9-11

Scleromyxedema is a rare condition involving the deposition of mucinous material in the papillary dermis to cause the formation of infiltrative skin lesions.¹² It is thought that immunoglobulins and cytokines secreted by inflammatory cells lead to the synthesis of glycosaminoglycans, which then causes deposition of mucin in the dermis.¹³ The classic cutaneous features of scleromyxedema include waxy indurated papules and plaques with skin thickening throughout the entire body.¹² Our patient’s papules were not notably indurated and involved less than 50% of the total body surface area. An important diagnostic feature of scleromyxedema is monoclonal gammopathy, which our patient did not have. Intravenous immunoglobulin is the first-line treatment of scleromyxedema, and second-line treatments include systemic corticosteroids and thalidomide.¹⁴ Our patient also did not require treatment with intravenous immunoglobulin, as her rash improved with antiviral medication, which would not address the underlying inflammatory processes associated with scleromyxedema.

Trichostasis spinulosa is a rare hair follicle disorder consisting of dark, spiny, hyperkeratotic follicular papules that can be found on the extremities and face, especially the nose. The etiology is unknown, but risk factors include congenital dysplasia of hair follicles; exposure to UV light, dust, oil, or heat; chronic renal failure; Malassezia yeast; and Propionibacterium acnes. Adult women with darker skin types are most commonly affected by trichostasis spinulosa.^15,16 Our patient fit the epidemiologic demographic of trichostasis spinulosa, including a history of chronic renal failure. Her rash covered the face, nose, and arms; however, the papules were flesh colored, whereas trichostasis spinulosa would appear as black papules. Furthermore, yeast and bacterial infections have been identified as potential agents associated with trichostasis spinulosa; therefore, antiviral agents would be ineffective. Viable treatments for trichostasis spinulosa include emollients, topical keratolytic agents, retinoic acids, and lasers to remove abnormal hair follicles.^15,16

The Diagnosis: Trichodysplasia Spinulosa

A diagnosis of trichodysplasia spinulosa (TS) was rendered based on the clinical presentation— diffuse folliculocentric keratotic papules with spicules and leonine facies—coinciding with cyclosporine initiation. Biopsy was deferred given the classic presentation. The patient applied cidofovir cream 1% daily to lesions on the face. She was prescribed leflunomide 10 mg daily, which was later increased to 20 mg daily, for polyarthritis associated with systemic lupus erythematosus (SLE). Her transplant physician increased her cyclosporine dosage from 50 mg twice daily to 75 mg each morning and 50 mg each evening due to rising creatinine and donor-specific antibodies from the renal transplant. The patient’s TS eruption mildly improved 3 months after the cyclosporine dose was increased. To treat persistent lesions, oral valganciclovir was started at 450 mg once daily and later reduced to every other day due to leukopenia. After 3 months of taking valganciclovir 450 mg every other day, the patient’s TS rash resolved.

Trichodysplasia spinulosa is a rare condition caused by TS-associated polyomavirus¹ that may arise in immunosuppressed patients, especially in solid organ transplant recipients.² It is characterized by spiculated and folliculocentric papules, mainly on the face,¹ and often is diagnosed clinically, but if the presentation is not classic, a skin biopsy can help to confirm the diagnosis. Because of its rarity, treatment options do not have well-established efficacy¹ but include reducing immunosuppression and using the antivirals cidofovir¹ or valganciclovir³ to treat the polyomavirus. Topical retinoids,³ photodynamic therapy, ⁴ and leflunomide⁵ also may be effective.

Although the typical approach to treating TS is to reduce immunosuppression, this was not an option for our patient, as she required increased immunosuppression for the treatment of active SLE. Leflunomide can be used for SLE, and in some reports it can be effective for BK viremia in kidney transplant recipients⁵ as well as for TS in solid organ transplant recipients.⁶ Our patient showed improvement of the TS, BK viremia, renal function, and SLE while taking leflunomide and valganciclovir.

The differential diagnosis includes keratosis pilaris, lichen nitidus, scleromyxedema, and trichostasis spinulosa. Keratosis pilaris is a benign skin disorder consisting of patches of keratotic papules with varying degrees of erythema and inflammation that are formed by dead keratinocytes plugging the hair follicles and often are seen on the extremities, face, and trunk.⁷ Our patient’s papules were flesh colored with no notable background erythema. Additionally, the presence of leonine facies was atypical for keratosis pilaris. Acids, steroids, and kinase inhibitors are the most frequently used treatments for keratosis pilaris.⁸

Lichen nitidus is a skin condition characterized by multiple shiny, dome-shaped, flesh-colored papules usually found on the flexor surfaces of the arms, anterior trunk, and genitalia. It is mostly asymptomatic, but patients may experience pruritus. Most cases occur in children and young adults, with no obvious racial or gender predilection. The diagnosis often is clinical, but biopsy shows downward enlargement of the epidermal rete ridges surrounding a focal inflammatory infiltrate, known as a ball-in-claw configuration.^9-11 Lichen nitidus spontaneously resolves within a few years without treatment. Our patient did have flesh-colored papules on the arms and chest; however, major involvement of the face is not typical in lichen nitidus. Additionally, fine white spicules would not be seen in lichen nitidus. For severe generalized lichen nitidus, treatment options include topical corticosteroids, topical calcineurin inhibitors, oral antihistamines, or UV light to decrease inflammation.^9-11

Scleromyxedema is a rare condition involving the deposition of mucinous material in the papillary dermis to cause the formation of infiltrative skin lesions.¹² It is thought that immunoglobulins and cytokines secreted by inflammatory cells lead to the synthesis of glycosaminoglycans, which then causes deposition of mucin in the dermis.¹³ The classic cutaneous features of scleromyxedema include waxy indurated papules and plaques with skin thickening throughout the entire body.¹² Our patient’s papules were not notably indurated and involved less than 50% of the total body surface area. An important diagnostic feature of scleromyxedema is monoclonal gammopathy, which our patient did not have. Intravenous immunoglobulin is the first-line treatment of scleromyxedema, and second-line treatments include systemic corticosteroids and thalidomide.¹⁴ Our patient also did not require treatment with intravenous immunoglobulin, as her rash improved with antiviral medication, which would not address the underlying inflammatory processes associated with scleromyxedema.

Trichostasis spinulosa is a rare hair follicle disorder consisting of dark, spiny, hyperkeratotic follicular papules that can be found on the extremities and face, especially the nose. The etiology is unknown, but risk factors include congenital dysplasia of hair follicles; exposure to UV light, dust, oil, or heat; chronic renal failure; Malassezia yeast; and Propionibacterium acnes. Adult women with darker skin types are most commonly affected by trichostasis spinulosa.^15,16 Our patient fit the epidemiologic demographic of trichostasis spinulosa, including a history of chronic renal failure. Her rash covered the face, nose, and arms; however, the papules were flesh colored, whereas trichostasis spinulosa would appear as black papules. Furthermore, yeast and bacterial infections have been identified as potential agents associated with trichostasis spinulosa; therefore, antiviral agents would be ineffective. Viable treatments for trichostasis spinulosa include emollients, topical keratolytic agents, retinoic acids, and lasers to remove abnormal hair follicles.^15,16

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition that affects approximately 0.1% of the US population.^1,2 Severe disease or HS flares can lead patients to seek care through the emergency department (ED), with some requiring inpatient admission. ³ Inpatient hospitalization of patients with HS has increased over the last 2 decades, and patients with HS utilize emergency and inpatient care more frequently than those with other dermatologic conditions.^4,5 Minority patients and those of lower socioeconomic status are more likely to present to the ED for HS management due to limited access to care and other existing comorbid conditions. ⁴ In a 2022 study of the Nationwide Readmissions Database, the authors looked at hospital readmission rates of patients with HS compared with those with heart failure—both patient populations with chronic debilitating conditions. Results indicated that the hospital readmission rates for patients with HS surpassed those of patients with heart failure for that year, highlighting the need for improved inpatient management of HS.⁶

Patients with HS present to the ED with severe pain, fever, wound care, or the need for surgical intervention. The ED and inpatient hospital setting are locations in which physicians may not be as familiar with the diagnosis or treatment of HS, specifically flares or severe disease. ⁷ The inpatient care setting provides access to certain resources that can be challenging to obtain in the outpatient clinical setting, such as social workers and pain specialists, but also can prove challenging in obtaining other resources for HS management, such as advanced medical therapies. Given the increase in hospital- based care for HS and lack of widespread inpatient access to dermatology and HS experts, consensus recommendations for management of HS in the acute hospital setting would be beneficial. In our study, we sought to generate a collection of expert consensus statements providers can refer to when managing patients with HS in the inpatient setting.

Methods

The study team at the Wake Forest University School of Medicine (Winston-Salem, North Carolina)(M.N., R.P., L.C.S.) developed an initial set of consensus statements based on current published HS treatment guidelines,^8,9 publications on management of inpatient HS,³ published supportive care guidelines for Stevens-Johnson syndrome, 10 and personal clinical experience in managing inpatient HS, which resulted in 50 statements organized into the following categories: overall care, wound care, genital care, pain management, infection control, medical management, surgical management, nutrition, and transitional care guidelines. This study was approved by the Wake Forest University institutional review board (IRB00084257).

Participant Recruitment—Dermatologists were identified for participation in the study based on membership in the Society of Dermatology Hospitalists and the Hidradenitis Suppurativa Foundation or authorship of publications relevant to HS or inpatient dermatology. Dermatologists from larger academic institutions with HS specialty clinics and inpatient dermatology services also were identified. Participants were invited via email and could suggest other experts for inclusion. A total of 31 dermatologists were invited to participate in the study, with 26 agreeing to participate. All participating dermatologists were practicing in the United States.

Delphi Study—In the first round of the Delphi study, the participants were sent an online survey via REDCap in which they were asked to rank the appropriateness of each of the proposed 50 guideline statements on a scale of 1 (very inappropriate) to 9 (very appropriate). Participants also were able to provide commentary and feedback on each of the statements. Survey results were analyzed using the RAND/ UCLA Appropriateness Method.¹¹ For each statement, the median rating for appropriateness, interpercentile range (IPR), IPR adjusted for symmetry, and disagreement index (DI) were calculated (DI=IPR/IPR adjusted for symmetry). The 30th and 70th percentiles were used in the DI calculation as the upper and lower limits, respectively. A median rating for appropriateness of 1.0 to 3.9 was considered “inappropriate,” 4.0 to 6.9 was considered “uncertain appropriateness,” and 7.0 to 9.0 was “appropriate.” A DI value greater than or equal to 1 indicated a lack of consensus regarding the appropriateness of the statement. Following each round, participants received a copy of their responses along with the group median rank of each statement. Statements that did not reach consensus in the first Delphi round were revised based on feedback received by the participants, and a second survey with 14 statements was sent via REDCap 2 weeks later. The RAND/UCLA Appropriateness Method also was applied to this second Delphi round. After the second survey, participants received a copy of anonymized comments regarding the consensus statements and were allowed to provide additional final commentary to be included in the discussion of these recommendations.

Results

Twenty-six dermatologists completed the first-round survey, and 24 participants completed the second-round survey. All participants self-identified as having expertise in either HS (n=22 [85%]) or inpatient dermatology (n=17 [65%]), and 13 (50%) participants self-identified as experts in both HS and inpatient dermatology. All participants, except 1, were affiliated with an academic health system with inpatient dermatology services. The average length of time in practice as a dermatologist was 10 years (median, 9 years [range, 3–27 years]).

Of the 50 initial proposed consensus statements, 26 (52%) achieved consensus after the first round; 21 statements revealed DI calculations that did not achieve consensus. Two statements achieved consensus but received median ratings for appropriateness, indicating uncertain appropriateness; because of this, 1 statement was removed and 1 was revised based on participant feedback, resulting in 13 revised statements (eTable 1). Controversial topics in the consensus process included obtaining wound cultures and meaningful culture data interpretation, use of specific biologic medications in the inpatient setting, and use of intravenous ertapenem. Participant responses to these topics are discussed in detail below. Of these secondround statements, all achieved consensus. The final set of consensus statements can be found in eTable 2.

Comment

Our Delphi consensus study combined the expertise of both dermatologists who care for patients with HS and those with inpatient dermatology experience to produce a set of recommendations for the management of HS in the hospital care setting. A strength of this study is inclusion of many national leaders in both HS and inpatient dermatology, with some participants having developed the previously published HS treatment guidelines and others having participated in inpatient dermatology Delphi studies.8-10 The expertise is further strengthened by the geographically diverse institutional representation within the United States.

The final consensus recommendations included 40 statements covering a range of patient care issues, including use of appropriate inpatient subspecialists (care team), supportive care measures (wound care, pain control, genital care), disease-oriented treatment (medical management, surgical management), inpatient complications (infection control, nutrition), and successful transition back to outpatient management (transitional care). These recommendations are meant to serve as a resource for providers to consider when taking care of inpatient HS flares, recognizing that the complexity and individual circumstances of each patient are unique.

Delphi Consensus Recommendations Compared to Prior Guidelines—Several recommendations in the current study align with the previously published North American clinical management guidelines for HS.^8,9 Our recommendations agree with prior guidelines on the importance of disease staging and pain assessment using validated assessment tools as well as screening for HS comorbidities. There also is agreement in the potential benefit of involving pain specialists in the development of a comprehensive pain management plan. The inpatient care setting provides a unique opportunity to engage multiple specialists and collaborate on patient care in a timely manner. Our recommendations regarding surgical care also align with established guidelines in recommending incision and drainage as an acute bedside procedure best utilized for symptom relief in inflamed abscesses and relegating most other surgical management to the outpatient setting. Wound care recommendations also are similar, with our expert participants agreeing on individualizing dressing choices based on wound characteristics. A benefit of inpatient wound care is access to skilled nursing for dressing changes and potentially improved access to more sophisticated dressing materials. Our recommendations differ from the prior guidelines in our focus on severe HS, HS flares, and HS complications, which constitute the majority of inpatient disease management. We provide additional guidance on management of secondary infections, perianal fistulous disease, and importantly transitional care to optimize discharge planning.

Differing Opinions in Our Analysis—Despite the success of our Delphi consensus process, there were some differing opinions regarding certain aspects of inpatient HS management, which is to be expected given the lack of strong evidence-based research to support some of the recommended practices. There were differing opinions on the utility of wound culture data, with some participants feeling culture data could help with antibiotic susceptibility and resistance patterns, while others felt wound cultures represent bacterial colonization or biofilm formation.

Initial consensus statements in the first Delphi round were created for individual biologic medications but did not achieve consensus, and feedback on the use of biologics in the inpatient environment was mixed, largely due to logistic and insurance issues. Many participants felt biologic medication cost, difficulty obtaining inpatient reimbursement, health care resource utilization, and availability of biologics in different hospital systems prevented recommending the use of specific biologics during hospitalization. The one exception was in the case of a hospitalized patient who was already receiving infliximab for HS: there was consensus on ensuring the patient dosing was maximized, if appropriate, to 10 mg/kg.12 Ertapenem use also was controversial, with some participants using it as a bridge therapy to either outpatient biologic use or surgery, while others felt it was onerous and difficult to establish reliable access to secure intravenous administration and regular dosing once the patient left the inpatient setting.¹³ Others said they have experienced objections from infectious disease colleagues on the use of intravenous antibiotics, citing antibiotic stewardship concerns.

Patient Care in the Inpatient Setting—Prior literature suggests patients admitted as inpatients for HS tend to be of lower socioeconomic status and are admitted to larger urban teaching hospitals.^14,15 Patients with lower socioeconomic status have increased difficulty accessing health care resources; therefore, inpatient admission serves as an opportunity to provide a holistic HS assessment and coordinate resources for chronic outpatient management.

Study Limitations—This Delphi consensus study has some limitations. The existing literature on inpatient management of HS is limited, challenging our ability to assess the extent to which these published recommendations are already being implemented. Additionally, the study included HS and inpatient dermatology experts from the United States, which means the recommendations may not be generalizable to other countries. Most participants practiced dermatology at large tertiary care academic medical centers, which may limit the ability to implement recommendations in all US inpatient care settings such as small community-based hospitals; however, many of the supportive care guidelines such as pain control, wound care, nutritional support, and social work should be achievable in most inpatient care settings.

Conclusion

Given the increase in inpatient and ED health care utilization for HS, there is an urgent need for expert consensus recommendations on inpatient management of this unique patient population, which requires complex multidisciplinary care. Our recommendations are a resource for providers to utilize and potentially improve the standard of care we provide these patients.

Acknowledgment—We thank the Wake Forest University Clinical and Translational Science Institute (Winston- Salem, North Carolina) for providing statistical help.

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition that affects approximately 0.1% of the US population.^1,2 Severe disease or HS flares can lead patients to seek care through the emergency department (ED), with some requiring inpatient admission. ³ Inpatient hospitalization of patients with HS has increased over the last 2 decades, and patients with HS utilize emergency and inpatient care more frequently than those with other dermatologic conditions.^4,5 Minority patients and those of lower socioeconomic status are more likely to present to the ED for HS management due to limited access to care and other existing comorbid conditions. ⁴ In a 2022 study of the Nationwide Readmissions Database, the authors looked at hospital readmission rates of patients with HS compared with those with heart failure—both patient populations with chronic debilitating conditions. Results indicated that the hospital readmission rates for patients with HS surpassed those of patients with heart failure for that year, highlighting the need for improved inpatient management of HS.⁶

Patients with HS present to the ED with severe pain, fever, wound care, or the need for surgical intervention. The ED and inpatient hospital setting are locations in which physicians may not be as familiar with the diagnosis or treatment of HS, specifically flares or severe disease. ⁷ The inpatient care setting provides access to certain resources that can be challenging to obtain in the outpatient clinical setting, such as social workers and pain specialists, but also can prove challenging in obtaining other resources for HS management, such as advanced medical therapies. Given the increase in hospital- based care for HS and lack of widespread inpatient access to dermatology and HS experts, consensus recommendations for management of HS in the acute hospital setting would be beneficial. In our study, we sought to generate a collection of expert consensus statements providers can refer to when managing patients with HS in the inpatient setting.

Methods

The study team at the Wake Forest University School of Medicine (Winston-Salem, North Carolina)(M.N., R.P., L.C.S.) developed an initial set of consensus statements based on current published HS treatment guidelines,^8,9 publications on management of inpatient HS,³ published supportive care guidelines for Stevens-Johnson syndrome, 10 and personal clinical experience in managing inpatient HS, which resulted in 50 statements organized into the following categories: overall care, wound care, genital care, pain management, infection control, medical management, surgical management, nutrition, and transitional care guidelines. This study was approved by the Wake Forest University institutional review board (IRB00084257).

Participant Recruitment—Dermatologists were identified for participation in the study based on membership in the Society of Dermatology Hospitalists and the Hidradenitis Suppurativa Foundation or authorship of publications relevant to HS or inpatient dermatology. Dermatologists from larger academic institutions with HS specialty clinics and inpatient dermatology services also were identified. Participants were invited via email and could suggest other experts for inclusion. A total of 31 dermatologists were invited to participate in the study, with 26 agreeing to participate. All participating dermatologists were practicing in the United States.

Delphi Study—In the first round of the Delphi study, the participants were sent an online survey via REDCap in which they were asked to rank the appropriateness of each of the proposed 50 guideline statements on a scale of 1 (very inappropriate) to 9 (very appropriate). Participants also were able to provide commentary and feedback on each of the statements. Survey results were analyzed using the RAND/ UCLA Appropriateness Method.¹¹ For each statement, the median rating for appropriateness, interpercentile range (IPR), IPR adjusted for symmetry, and disagreement index (DI) were calculated (DI=IPR/IPR adjusted for symmetry). The 30th and 70th percentiles were used in the DI calculation as the upper and lower limits, respectively. A median rating for appropriateness of 1.0 to 3.9 was considered “inappropriate,” 4.0 to 6.9 was considered “uncertain appropriateness,” and 7.0 to 9.0 was “appropriate.” A DI value greater than or equal to 1 indicated a lack of consensus regarding the appropriateness of the statement. Following each round, participants received a copy of their responses along with the group median rank of each statement. Statements that did not reach consensus in the first Delphi round were revised based on feedback received by the participants, and a second survey with 14 statements was sent via REDCap 2 weeks later. The RAND/UCLA Appropriateness Method also was applied to this second Delphi round. After the second survey, participants received a copy of anonymized comments regarding the consensus statements and were allowed to provide additional final commentary to be included in the discussion of these recommendations.

Results

Twenty-six dermatologists completed the first-round survey, and 24 participants completed the second-round survey. All participants self-identified as having expertise in either HS (n=22 [85%]) or inpatient dermatology (n=17 [65%]), and 13 (50%) participants self-identified as experts in both HS and inpatient dermatology. All participants, except 1, were affiliated with an academic health system with inpatient dermatology services. The average length of time in practice as a dermatologist was 10 years (median, 9 years [range, 3–27 years]).

Of the 50 initial proposed consensus statements, 26 (52%) achieved consensus after the first round; 21 statements revealed DI calculations that did not achieve consensus. Two statements achieved consensus but received median ratings for appropriateness, indicating uncertain appropriateness; because of this, 1 statement was removed and 1 was revised based on participant feedback, resulting in 13 revised statements (eTable 1). Controversial topics in the consensus process included obtaining wound cultures and meaningful culture data interpretation, use of specific biologic medications in the inpatient setting, and use of intravenous ertapenem. Participant responses to these topics are discussed in detail below. Of these secondround statements, all achieved consensus. The final set of consensus statements can be found in eTable 2.

Comment

Our Delphi consensus study combined the expertise of both dermatologists who care for patients with HS and those with inpatient dermatology experience to produce a set of recommendations for the management of HS in the hospital care setting. A strength of this study is inclusion of many national leaders in both HS and inpatient dermatology, with some participants having developed the previously published HS treatment guidelines and others having participated in inpatient dermatology Delphi studies.8-10 The expertise is further strengthened by the geographically diverse institutional representation within the United States.

The final consensus recommendations included 40 statements covering a range of patient care issues, including use of appropriate inpatient subspecialists (care team), supportive care measures (wound care, pain control, genital care), disease-oriented treatment (medical management, surgical management), inpatient complications (infection control, nutrition), and successful transition back to outpatient management (transitional care). These recommendations are meant to serve as a resource for providers to consider when taking care of inpatient HS flares, recognizing that the complexity and individual circumstances of each patient are unique.

Delphi Consensus Recommendations Compared to Prior Guidelines—Several recommendations in the current study align with the previously published North American clinical management guidelines for HS.^8,9 Our recommendations agree with prior guidelines on the importance of disease staging and pain assessment using validated assessment tools as well as screening for HS comorbidities. There also is agreement in the potential benefit of involving pain specialists in the development of a comprehensive pain management plan. The inpatient care setting provides a unique opportunity to engage multiple specialists and collaborate on patient care in a timely manner. Our recommendations regarding surgical care also align with established guidelines in recommending incision and drainage as an acute bedside procedure best utilized for symptom relief in inflamed abscesses and relegating most other surgical management to the outpatient setting. Wound care recommendations also are similar, with our expert participants agreeing on individualizing dressing choices based on wound characteristics. A benefit of inpatient wound care is access to skilled nursing for dressing changes and potentially improved access to more sophisticated dressing materials. Our recommendations differ from the prior guidelines in our focus on severe HS, HS flares, and HS complications, which constitute the majority of inpatient disease management. We provide additional guidance on management of secondary infections, perianal fistulous disease, and importantly transitional care to optimize discharge planning.

Differing Opinions in Our Analysis—Despite the success of our Delphi consensus process, there were some differing opinions regarding certain aspects of inpatient HS management, which is to be expected given the lack of strong evidence-based research to support some of the recommended practices. There were differing opinions on the utility of wound culture data, with some participants feeling culture data could help with antibiotic susceptibility and resistance patterns, while others felt wound cultures represent bacterial colonization or biofilm formation.

Initial consensus statements in the first Delphi round were created for individual biologic medications but did not achieve consensus, and feedback on the use of biologics in the inpatient environment was mixed, largely due to logistic and insurance issues. Many participants felt biologic medication cost, difficulty obtaining inpatient reimbursement, health care resource utilization, and availability of biologics in different hospital systems prevented recommending the use of specific biologics during hospitalization. The one exception was in the case of a hospitalized patient who was already receiving infliximab for HS: there was consensus on ensuring the patient dosing was maximized, if appropriate, to 10 mg/kg.12 Ertapenem use also was controversial, with some participants using it as a bridge therapy to either outpatient biologic use or surgery, while others felt it was onerous and difficult to establish reliable access to secure intravenous administration and regular dosing once the patient left the inpatient setting.¹³ Others said they have experienced objections from infectious disease colleagues on the use of intravenous antibiotics, citing antibiotic stewardship concerns.

Patient Care in the Inpatient Setting—Prior literature suggests patients admitted as inpatients for HS tend to be of lower socioeconomic status and are admitted to larger urban teaching hospitals.^14,15 Patients with lower socioeconomic status have increased difficulty accessing health care resources; therefore, inpatient admission serves as an opportunity to provide a holistic HS assessment and coordinate resources for chronic outpatient management.

Study Limitations—This Delphi consensus study has some limitations. The existing literature on inpatient management of HS is limited, challenging our ability to assess the extent to which these published recommendations are already being implemented. Additionally, the study included HS and inpatient dermatology experts from the United States, which means the recommendations may not be generalizable to other countries. Most participants practiced dermatology at large tertiary care academic medical centers, which may limit the ability to implement recommendations in all US inpatient care settings such as small community-based hospitals; however, many of the supportive care guidelines such as pain control, wound care, nutritional support, and social work should be achievable in most inpatient care settings.

Conclusion

Given the increase in inpatient and ED health care utilization for HS, there is an urgent need for expert consensus recommendations on inpatient management of this unique patient population, which requires complex multidisciplinary care. Our recommendations are a resource for providers to utilize and potentially improve the standard of care we provide these patients.

Acknowledgment—We thank the Wake Forest University Clinical and Translational Science Institute (Winston- Salem, North Carolina) for providing statistical help.

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition that affects approximately 0.1% of the US population.^1,2 Severe disease or HS flares can lead patients to seek care through the emergency department (ED), with some requiring inpatient admission. ³ Inpatient hospitalization of patients with HS has increased over the last 2 decades, and patients with HS utilize emergency and inpatient care more frequently than those with other dermatologic conditions.^4,5 Minority patients and those of lower socioeconomic status are more likely to present to the ED for HS management due to limited access to care and other existing comorbid conditions. ⁴ In a 2022 study of the Nationwide Readmissions Database, the authors looked at hospital readmission rates of patients with HS compared with those with heart failure—both patient populations with chronic debilitating conditions. Results indicated that the hospital readmission rates for patients with HS surpassed those of patients with heart failure for that year, highlighting the need for improved inpatient management of HS.⁶

Patients with HS present to the ED with severe pain, fever, wound care, or the need for surgical intervention. The ED and inpatient hospital setting are locations in which physicians may not be as familiar with the diagnosis or treatment of HS, specifically flares or severe disease. ⁷ The inpatient care setting provides access to certain resources that can be challenging to obtain in the outpatient clinical setting, such as social workers and pain specialists, but also can prove challenging in obtaining other resources for HS management, such as advanced medical therapies. Given the increase in hospital- based care for HS and lack of widespread inpatient access to dermatology and HS experts, consensus recommendations for management of HS in the acute hospital setting would be beneficial. In our study, we sought to generate a collection of expert consensus statements providers can refer to when managing patients with HS in the inpatient setting.

Methods

The study team at the Wake Forest University School of Medicine (Winston-Salem, North Carolina)(M.N., R.P., L.C.S.) developed an initial set of consensus statements based on current published HS treatment guidelines,^8,9 publications on management of inpatient HS,³ published supportive care guidelines for Stevens-Johnson syndrome, 10 and personal clinical experience in managing inpatient HS, which resulted in 50 statements organized into the following categories: overall care, wound care, genital care, pain management, infection control, medical management, surgical management, nutrition, and transitional care guidelines. This study was approved by the Wake Forest University institutional review board (IRB00084257).

Participant Recruitment—Dermatologists were identified for participation in the study based on membership in the Society of Dermatology Hospitalists and the Hidradenitis Suppurativa Foundation or authorship of publications relevant to HS or inpatient dermatology. Dermatologists from larger academic institutions with HS specialty clinics and inpatient dermatology services also were identified. Participants were invited via email and could suggest other experts for inclusion. A total of 31 dermatologists were invited to participate in the study, with 26 agreeing to participate. All participating dermatologists were practicing in the United States.

Delphi Study—In the first round of the Delphi study, the participants were sent an online survey via REDCap in which they were asked to rank the appropriateness of each of the proposed 50 guideline statements on a scale of 1 (very inappropriate) to 9 (very appropriate). Participants also were able to provide commentary and feedback on each of the statements. Survey results were analyzed using the RAND/ UCLA Appropriateness Method.¹¹ For each statement, the median rating for appropriateness, interpercentile range (IPR), IPR adjusted for symmetry, and disagreement index (DI) were calculated (DI=IPR/IPR adjusted for symmetry). The 30th and 70th percentiles were used in the DI calculation as the upper and lower limits, respectively. A median rating for appropriateness of 1.0 to 3.9 was considered “inappropriate,” 4.0 to 6.9 was considered “uncertain appropriateness,” and 7.0 to 9.0 was “appropriate.” A DI value greater than or equal to 1 indicated a lack of consensus regarding the appropriateness of the statement. Following each round, participants received a copy of their responses along with the group median rank of each statement. Statements that did not reach consensus in the first Delphi round were revised based on feedback received by the participants, and a second survey with 14 statements was sent via REDCap 2 weeks later. The RAND/UCLA Appropriateness Method also was applied to this second Delphi round. After the second survey, participants received a copy of anonymized comments regarding the consensus statements and were allowed to provide additional final commentary to be included in the discussion of these recommendations.

Results

Twenty-six dermatologists completed the first-round survey, and 24 participants completed the second-round survey. All participants self-identified as having expertise in either HS (n=22 [85%]) or inpatient dermatology (n=17 [65%]), and 13 (50%) participants self-identified as experts in both HS and inpatient dermatology. All participants, except 1, were affiliated with an academic health system with inpatient dermatology services. The average length of time in practice as a dermatologist was 10 years (median, 9 years [range, 3–27 years]).

Of the 50 initial proposed consensus statements, 26 (52%) achieved consensus after the first round; 21 statements revealed DI calculations that did not achieve consensus. Two statements achieved consensus but received median ratings for appropriateness, indicating uncertain appropriateness; because of this, 1 statement was removed and 1 was revised based on participant feedback, resulting in 13 revised statements (eTable 1). Controversial topics in the consensus process included obtaining wound cultures and meaningful culture data interpretation, use of specific biologic medications in the inpatient setting, and use of intravenous ertapenem. Participant responses to these topics are discussed in detail below. Of these secondround statements, all achieved consensus. The final set of consensus statements can be found in eTable 2.

Comment

Our Delphi consensus study combined the expertise of both dermatologists who care for patients with HS and those with inpatient dermatology experience to produce a set of recommendations for the management of HS in the hospital care setting. A strength of this study is inclusion of many national leaders in both HS and inpatient dermatology, with some participants having developed the previously published HS treatment guidelines and others having participated in inpatient dermatology Delphi studies.8-10 The expertise is further strengthened by the geographically diverse institutional representation within the United States.

The final consensus recommendations included 40 statements covering a range of patient care issues, including use of appropriate inpatient subspecialists (care team), supportive care measures (wound care, pain control, genital care), disease-oriented treatment (medical management, surgical management), inpatient complications (infection control, nutrition), and successful transition back to outpatient management (transitional care). These recommendations are meant to serve as a resource for providers to consider when taking care of inpatient HS flares, recognizing that the complexity and individual circumstances of each patient are unique.

Delphi Consensus Recommendations Compared to Prior Guidelines—Several recommendations in the current study align with the previously published North American clinical management guidelines for HS.^8,9 Our recommendations agree with prior guidelines on the importance of disease staging and pain assessment using validated assessment tools as well as screening for HS comorbidities. There also is agreement in the potential benefit of involving pain specialists in the development of a comprehensive pain management plan. The inpatient care setting provides a unique opportunity to engage multiple specialists and collaborate on patient care in a timely manner. Our recommendations regarding surgical care also align with established guidelines in recommending incision and drainage as an acute bedside procedure best utilized for symptom relief in inflamed abscesses and relegating most other surgical management to the outpatient setting. Wound care recommendations also are similar, with our expert participants agreeing on individualizing dressing choices based on wound characteristics. A benefit of inpatient wound care is access to skilled nursing for dressing changes and potentially improved access to more sophisticated dressing materials. Our recommendations differ from the prior guidelines in our focus on severe HS, HS flares, and HS complications, which constitute the majority of inpatient disease management. We provide additional guidance on management of secondary infections, perianal fistulous disease, and importantly transitional care to optimize discharge planning.

Differing Opinions in Our Analysis—Despite the success of our Delphi consensus process, there were some differing opinions regarding certain aspects of inpatient HS management, which is to be expected given the lack of strong evidence-based research to support some of the recommended practices. There were differing opinions on the utility of wound culture data, with some participants feeling culture data could help with antibiotic susceptibility and resistance patterns, while others felt wound cultures represent bacterial colonization or biofilm formation.

Initial consensus statements in the first Delphi round were created for individual biologic medications but did not achieve consensus, and feedback on the use of biologics in the inpatient environment was mixed, largely due to logistic and insurance issues. Many participants felt biologic medication cost, difficulty obtaining inpatient reimbursement, health care resource utilization, and availability of biologics in different hospital systems prevented recommending the use of specific biologics during hospitalization. The one exception was in the case of a hospitalized patient who was already receiving infliximab for HS: there was consensus on ensuring the patient dosing was maximized, if appropriate, to 10 mg/kg.12 Ertapenem use also was controversial, with some participants using it as a bridge therapy to either outpatient biologic use or surgery, while others felt it was onerous and difficult to establish reliable access to secure intravenous administration and regular dosing once the patient left the inpatient setting.¹³ Others said they have experienced objections from infectious disease colleagues on the use of intravenous antibiotics, citing antibiotic stewardship concerns.

Patient Care in the Inpatient Setting—Prior literature suggests patients admitted as inpatients for HS tend to be of lower socioeconomic status and are admitted to larger urban teaching hospitals.^14,15 Patients with lower socioeconomic status have increased difficulty accessing health care resources; therefore, inpatient admission serves as an opportunity to provide a holistic HS assessment and coordinate resources for chronic outpatient management.

Study Limitations—This Delphi consensus study has some limitations. The existing literature on inpatient management of HS is limited, challenging our ability to assess the extent to which these published recommendations are already being implemented. Additionally, the study included HS and inpatient dermatology experts from the United States, which means the recommendations may not be generalizable to other countries. Most participants practiced dermatology at large tertiary care academic medical centers, which may limit the ability to implement recommendations in all US inpatient care settings such as small community-based hospitals; however, many of the supportive care guidelines such as pain control, wound care, nutritional support, and social work should be achievable in most inpatient care settings.

Conclusion

Given the increase in inpatient and ED health care utilization for HS, there is an urgent need for expert consensus recommendations on inpatient management of this unique patient population, which requires complex multidisciplinary care. Our recommendations are a resource for providers to utilize and potentially improve the standard of care we provide these patients.

Acknowledgment—We thank the Wake Forest University Clinical and Translational Science Institute (Winston- Salem, North Carolina) for providing statistical help.

The Diagnosis: Erythema Ab Igne

Based on the patient's long-standing history of back pain treated with heating pads as well as the normal laboratory findings and skin examination, a diagnosis of erythema ab igne (EAI) was made.

Erythema ab igne presents as reticulated brownish erythema or hyperpigmentation on sites exposed to prolonged use of heat sources such as heating pads, laptops, and space heaters. Erythema ab igne most commonly affects the lower back, thighs, or legs^1-6; however, EAI can appear on atypical sites such as the forehead and eyebrows due to newer technology (eg, virtual reality headsets).⁷ The level of heat required for EAI to occur is below the threshold for thermal burns (<45 °C [113 °F]).1 Erythema ab igne can occur at any age, and woman are more commonly affected than men.⁸ The pathophysiology currently is unknown; however, recurrent and prolonged heat exposure may damage superficial vessels. As a result, hemosiderin accumulates in the skin, and hyperpigmentation subsequently occurs.⁹

The diagnosis of EAI is clinical, and early stages of the rash present as blanching reticulated erythema in areas associated with heat exposure. If the offending source of heat is not removed, EAI can progress to nonblanching, fixed, hyperpigmented plaques with skin atrophy, bullae, or hyperkeratosis. Patients often are asymptomatic; however, mild burning may occur.² Histopathology reveals cellular atypia, epidermal atrophy, dilation of dermal blood vessels, a minute inflammatory infiltrate, and keratinocyte apoptosis.¹⁰ Skin biopsy may be necessary in cases of suspected malignancy due to chronic heat exposure. Lesions that ulcerate or evolve should raise suspicion for malignancy.¹¹ Squamous cell carcinoma is the most common malignancy associated with EAI; other malignancies that may manifest include basal cell carcinoma, Merkel cell carcinoma, or cutaneous marginal zone lymphoma.^2,12-14

Erythema ab igne often is mistaken for livedo reticularis, which appears more erythematous without hyperpigmentation or epidermal changes and may be associated with a pathologic state.¹⁵ The differential diagnosis in our patient, who was in her 40s with a history of fatigue and joint pain, included livedo reticularis associated with lupus; however, the history of heating pad use, normal laboratory findings, and presence of epidermal changes suggested EAI. Lupus typically affects the hand and knee joints.¹⁶ Additionally, livedo reticularis more commonly appears on the legs.¹⁵

Other differentials for EAI include livedo racemosa, cutaneous T-cell lymphoma, and cutis marmorata. Livedo racemosa presents with broken rings of erythema in young to middle-aged women and primarily affects the trunk and proximal limbs. It is associated with an underlying condition such as polyarteritis nodosa and less commonly with lupus erythematosus with antiphospholipid or Sneddon syndrome.^15,17 Cutaneous T-cell lymphoma typically manifests with poikilodermatous patches larger than the palm, especially in covered areas of skin.¹⁸ Cutis marmorata is transient and temperature dependent.⁹

The key intervention for EAI is removal of the offending heat source.² Patients should be counseled that the erythema and hyperpigmentation may take months to years to resolve. Topical hydroquinone or tretinoin may be used in cases of persistent hyperpigmentation.¹⁹ Patients who continue to use heating pads for long-standing pain should be advised to limit their use to short intervals without occlusion. If malignancy is a concern, a biopsy should be performed.²⁰

The Diagnosis: Erythema Ab Igne

Based on the patient's long-standing history of back pain treated with heating pads as well as the normal laboratory findings and skin examination, a diagnosis of erythema ab igne (EAI) was made.

Erythema ab igne presents as reticulated brownish erythema or hyperpigmentation on sites exposed to prolonged use of heat sources such as heating pads, laptops, and space heaters. Erythema ab igne most commonly affects the lower back, thighs, or legs^1-6; however, EAI can appear on atypical sites such as the forehead and eyebrows due to newer technology (eg, virtual reality headsets).⁷ The level of heat required for EAI to occur is below the threshold for thermal burns (<45 °C [113 °F]).1 Erythema ab igne can occur at any age, and woman are more commonly affected than men.⁸ The pathophysiology currently is unknown; however, recurrent and prolonged heat exposure may damage superficial vessels. As a result, hemosiderin accumulates in the skin, and hyperpigmentation subsequently occurs.⁹

The diagnosis of EAI is clinical, and early stages of the rash present as blanching reticulated erythema in areas associated with heat exposure. If the offending source of heat is not removed, EAI can progress to nonblanching, fixed, hyperpigmented plaques with skin atrophy, bullae, or hyperkeratosis. Patients often are asymptomatic; however, mild burning may occur.² Histopathology reveals cellular atypia, epidermal atrophy, dilation of dermal blood vessels, a minute inflammatory infiltrate, and keratinocyte apoptosis.¹⁰ Skin biopsy may be necessary in cases of suspected malignancy due to chronic heat exposure. Lesions that ulcerate or evolve should raise suspicion for malignancy.¹¹ Squamous cell carcinoma is the most common malignancy associated with EAI; other malignancies that may manifest include basal cell carcinoma, Merkel cell carcinoma, or cutaneous marginal zone lymphoma.^2,12-14

Erythema ab igne often is mistaken for livedo reticularis, which appears more erythematous without hyperpigmentation or epidermal changes and may be associated with a pathologic state.¹⁵ The differential diagnosis in our patient, who was in her 40s with a history of fatigue and joint pain, included livedo reticularis associated with lupus; however, the history of heating pad use, normal laboratory findings, and presence of epidermal changes suggested EAI. Lupus typically affects the hand and knee joints.¹⁶ Additionally, livedo reticularis more commonly appears on the legs.¹⁵

Other differentials for EAI include livedo racemosa, cutaneous T-cell lymphoma, and cutis marmorata. Livedo racemosa presents with broken rings of erythema in young to middle-aged women and primarily affects the trunk and proximal limbs. It is associated with an underlying condition such as polyarteritis nodosa and less commonly with lupus erythematosus with antiphospholipid or Sneddon syndrome.^15,17 Cutaneous T-cell lymphoma typically manifests with poikilodermatous patches larger than the palm, especially in covered areas of skin.¹⁸ Cutis marmorata is transient and temperature dependent.⁹

The key intervention for EAI is removal of the offending heat source.² Patients should be counseled that the erythema and hyperpigmentation may take months to years to resolve. Topical hydroquinone or tretinoin may be used in cases of persistent hyperpigmentation.¹⁹ Patients who continue to use heating pads for long-standing pain should be advised to limit their use to short intervals without occlusion. If malignancy is a concern, a biopsy should be performed.²⁰

The Diagnosis: Erythema Ab Igne

Based on the patient's long-standing history of back pain treated with heating pads as well as the normal laboratory findings and skin examination, a diagnosis of erythema ab igne (EAI) was made.

Erythema ab igne presents as reticulated brownish erythema or hyperpigmentation on sites exposed to prolonged use of heat sources such as heating pads, laptops, and space heaters. Erythema ab igne most commonly affects the lower back, thighs, or legs^1-6; however, EAI can appear on atypical sites such as the forehead and eyebrows due to newer technology (eg, virtual reality headsets).⁷ The level of heat required for EAI to occur is below the threshold for thermal burns (<45 °C [113 °F]).1 Erythema ab igne can occur at any age, and woman are more commonly affected than men.⁸ The pathophysiology currently is unknown; however, recurrent and prolonged heat exposure may damage superficial vessels. As a result, hemosiderin accumulates in the skin, and hyperpigmentation subsequently occurs.⁹

The diagnosis of EAI is clinical, and early stages of the rash present as blanching reticulated erythema in areas associated with heat exposure. If the offending source of heat is not removed, EAI can progress to nonblanching, fixed, hyperpigmented plaques with skin atrophy, bullae, or hyperkeratosis. Patients often are asymptomatic; however, mild burning may occur.² Histopathology reveals cellular atypia, epidermal atrophy, dilation of dermal blood vessels, a minute inflammatory infiltrate, and keratinocyte apoptosis.¹⁰ Skin biopsy may be necessary in cases of suspected malignancy due to chronic heat exposure. Lesions that ulcerate or evolve should raise suspicion for malignancy.¹¹ Squamous cell carcinoma is the most common malignancy associated with EAI; other malignancies that may manifest include basal cell carcinoma, Merkel cell carcinoma, or cutaneous marginal zone lymphoma.^2,12-14

Erythema ab igne often is mistaken for livedo reticularis, which appears more erythematous without hyperpigmentation or epidermal changes and may be associated with a pathologic state.¹⁵ The differential diagnosis in our patient, who was in her 40s with a history of fatigue and joint pain, included livedo reticularis associated with lupus; however, the history of heating pad use, normal laboratory findings, and presence of epidermal changes suggested EAI. Lupus typically affects the hand and knee joints.¹⁶ Additionally, livedo reticularis more commonly appears on the legs.¹⁵

Other differentials for EAI include livedo racemosa, cutaneous T-cell lymphoma, and cutis marmorata. Livedo racemosa presents with broken rings of erythema in young to middle-aged women and primarily affects the trunk and proximal limbs. It is associated with an underlying condition such as polyarteritis nodosa and less commonly with lupus erythematosus with antiphospholipid or Sneddon syndrome.^15,17 Cutaneous T-cell lymphoma typically manifests with poikilodermatous patches larger than the palm, especially in covered areas of skin.¹⁸ Cutis marmorata is transient and temperature dependent.⁹

The key intervention for EAI is removal of the offending heat source.² Patients should be counseled that the erythema and hyperpigmentation may take months to years to resolve. Topical hydroquinone or tretinoin may be used in cases of persistent hyperpigmentation.¹⁹ Patients who continue to use heating pads for long-standing pain should be advised to limit their use to short intervals without occlusion. If malignancy is a concern, a biopsy should be performed.²⁰