Lorraine Young, MD

To the Editor:

Lichen amyloidosis (LA) classically presents as a pruritic, hyperkeratotic, papular eruption localized to the pretibial surface of the legs.¹ Nonpruritic and generalized variants have been reported but are rare.² Although it is the most common subtype of primary localized cutaneous amyloidosis, LA is a benign condition but is difficult to eradicate.¹ The precise pathophysiology is poorly understood, but chronic frictional irritation is closely associated with the eruption. We present a nongeneralized case of LA in an atypical location.

A healthy 30-year-old woman presented with an intermittent itchy rash on the elbows and knees of 2 years’ duration. The patient was first diagnosed with lichen simplex chronicus (LSC) and initially responded well to treatment with fluocinonide ointment 0.05%. Nearly 2 years after the initial presentation, she developed recurrent symptoms and sought further treatment. She reported frequent scratching in association with episodes of anxiety. Examination revealed numerous 1- to 3-mm, flesh-colored to light brown, monomorphic, dome-shaped papules over the extensor surfaces of the bilateral arms and left pretibial surface (Figure 1).

^4-6

The possibility remains that this patient first presented with LSC 2 years prior and secondarily developed LA due to chronic trauma. Indeed, LA has been proposed as a variant of LSC. In both conditions, scratching seems to be the most important factor in the development of lesions. It has been proposed that treatment should primarily focus on the amelioration of pruritus.⁵

Five percent to 10% of cases of LA have been found to have some form of upper extremity involvement.⁷ However, these cases typically are associated with a generalized presentation involving the trunk and arms.^2,7 Our patient had no evidence of disease elsewhere. When evaluating a localized, pruritic, monomorphic, papular eruption on the extensor surfaces of the arms, LA may be an important consideration.

To the Editor:

Lichen amyloidosis (LA) classically presents as a pruritic, hyperkeratotic, papular eruption localized to the pretibial surface of the legs.¹ Nonpruritic and generalized variants have been reported but are rare.² Although it is the most common subtype of primary localized cutaneous amyloidosis, LA is a benign condition but is difficult to eradicate.¹ The precise pathophysiology is poorly understood, but chronic frictional irritation is closely associated with the eruption. We present a nongeneralized case of LA in an atypical location.

A healthy 30-year-old woman presented with an intermittent itchy rash on the elbows and knees of 2 years’ duration. The patient was first diagnosed with lichen simplex chronicus (LSC) and initially responded well to treatment with fluocinonide ointment 0.05%. Nearly 2 years after the initial presentation, she developed recurrent symptoms and sought further treatment. She reported frequent scratching in association with episodes of anxiety. Examination revealed numerous 1- to 3-mm, flesh-colored to light brown, monomorphic, dome-shaped papules over the extensor surfaces of the bilateral arms and left pretibial surface (Figure 1).

^4-6

The possibility remains that this patient first presented with LSC 2 years prior and secondarily developed LA due to chronic trauma. Indeed, LA has been proposed as a variant of LSC. In both conditions, scratching seems to be the most important factor in the development of lesions. It has been proposed that treatment should primarily focus on the amelioration of pruritus.⁵

Five percent to 10% of cases of LA have been found to have some form of upper extremity involvement.⁷ However, these cases typically are associated with a generalized presentation involving the trunk and arms.^2,7 Our patient had no evidence of disease elsewhere. When evaluating a localized, pruritic, monomorphic, papular eruption on the extensor surfaces of the arms, LA may be an important consideration.

To the Editor:

Lichen amyloidosis (LA) classically presents as a pruritic, hyperkeratotic, papular eruption localized to the pretibial surface of the legs.¹ Nonpruritic and generalized variants have been reported but are rare.² Although it is the most common subtype of primary localized cutaneous amyloidosis, LA is a benign condition but is difficult to eradicate.¹ The precise pathophysiology is poorly understood, but chronic frictional irritation is closely associated with the eruption. We present a nongeneralized case of LA in an atypical location.

A healthy 30-year-old woman presented with an intermittent itchy rash on the elbows and knees of 2 years’ duration. The patient was first diagnosed with lichen simplex chronicus (LSC) and initially responded well to treatment with fluocinonide ointment 0.05%. Nearly 2 years after the initial presentation, she developed recurrent symptoms and sought further treatment. She reported frequent scratching in association with episodes of anxiety. Examination revealed numerous 1- to 3-mm, flesh-colored to light brown, monomorphic, dome-shaped papules over the extensor surfaces of the bilateral arms and left pretibial surface (Figure 1).

^4-6

The possibility remains that this patient first presented with LSC 2 years prior and secondarily developed LA due to chronic trauma. Indeed, LA has been proposed as a variant of LSC. In both conditions, scratching seems to be the most important factor in the development of lesions. It has been proposed that treatment should primarily focus on the amelioration of pruritus.⁵

Five percent to 10% of cases of LA have been found to have some form of upper extremity involvement.⁷ However, these cases typically are associated with a generalized presentation involving the trunk and arms.^2,7 Our patient had no evidence of disease elsewhere. When evaluating a localized, pruritic, monomorphic, papular eruption on the extensor surfaces of the arms, LA may be an important consideration.

To the Editor:

Epidermolysis bullosa (EB) was first described in 1886, with the first classification scheme proposed in 1962 utilizing transmission electron microscopy (TEM) findings to delineate categories: epidermolytic (EB simplex [EBS]), lucidolytic (junctional EB), and dermolytic (dystrophic EB).¹ Localized EBS (EBS-loc) is an autosomal-dominant disorder caused by negative mutations in keratin-5 and keratin-14, proteins expressed in the intermediate filaments of basal keratinocytes, which result in fragility of the skin in response to minor trauma.² The incidence of EBS-loc is approximately 10 to 30 cases per million live births, with the age of presentation typically between the first and third decades of life.^3,4 Because EBS-loc is the most common and often mildest form of EB, not all patients present for medical evaluation and true prevalence may be underestimated.⁴ We report a case of EBS-loc.

A 26-year-old woman with no notable medical history presented to the dermatology clinic for evaluation of skin blisters that had been intermittently present since infancy. The blisters primarily occurred on the feet, but she did occasionally develop blisters on the hands, knees, and elbows and at sites of friction or trauma (eg, bra line, medial thighs) following exercise. The blisters were worsened by heat and tight-fitting shoes. Because of the painful nature of the blisters, she would lance them with a needle. On the medial thighs, she utilized nonstick and gauze bandage roll dressings to minimize friction. A review of systems was positive for hyperhidrosis. Her family history revealed multiple family members with blisters involving the feet and areas of friction or trauma for 4 generations with no known diagnosis.

Physical examination revealed multiple tense bullae and calluses scattered over the bilateral plantar and distal dorsal feet with a few healing, superficially eroded, erythematous papules and plaques on the bilateral medial thighs (Figure 1). A biopsy from an induced blister on the right dorsal second toe was performed and sent in glutaraldehyde to the Epidermolysis Bullosa Clinic at Stanford University (Redwood City, California) for electron microscopy, which revealed lysis within the basal keratinocytes through the tonofilaments with continuous and intact lamina densa and lamina lucida (Figure 2). In this clinical context with the relevant family history, the findings were consistent with the diagnosis of EBS-loc (formerly Weber-Cockayne syndrome).²

Light microscopy does not have a notable role in diagnosis of classic forms of inherited EB unless another autoimmune blistering disorder is suspected.^2,5 Both TEM and immunofluorescence mapping are used to diagnose EB.¹ DNA mutational analysis is not considered a first-line diagnostic test for EB given it is a costly labor-intensive technique with limited access at present, but it may be considered in settings of prenatal diagnosis or in vitro fertilization.¹ Biopsy of a freshly induced blister should be performed, as early reepithelialization of an existing blister makes it difficult to establish the level of cleavage.⁵ Applying firm pressure using a pencil eraser and rotating it on intact skin induces a subclinical blister. Two punch biopsies (4 mm) at the edge of the blister with one-third lesional and two-thirds perilesional skin should be obtained, with one biopsy sent for immunofluorescence mapping in Michel fixative and the other for TEM in glutaraldehyde.^3,5 Transmission electron microscopy of an induced blister in EBS-loc shows cleavage within the most inferior portion of the basilar keratinocyte.² Immunofluorescence mapping with anti–epidermal basement membrane monoclonal antibodies can distinguish between EB subtypes and assess expression of specific skin-associated proteins on both a qualitative or semiquantitative basis, providing insight on which structural protein is mutated.^1,5

No specific treatments are available for EBS-loc. Mainstays of treatment include prevention of mechanical trauma and secondary infection. Hyperhidrosis of thepalms and soles may be treated with topical aluminum chloride hexahydrate or injections of botulinum toxin type A.^2,6 Patients have normal life expectancy, though some cases may have complications with substantial morbidity.¹ Awareness of this disease, its clinical course, and therapeutic options will allow physicians to more appropriately counsel patients on the disease process.

Localized EBS may be more common than previously thought, as not all patients seek medical care. Given its impact on patient quality of life, it is important for clinicians to recognize EBS-loc. Although no specific treatments are available, wound care counseling and explanation of the genetics of the disease should be provided to patients.

To the Editor:

Epidermolysis bullosa (EB) was first described in 1886, with the first classification scheme proposed in 1962 utilizing transmission electron microscopy (TEM) findings to delineate categories: epidermolytic (EB simplex [EBS]), lucidolytic (junctional EB), and dermolytic (dystrophic EB).¹ Localized EBS (EBS-loc) is an autosomal-dominant disorder caused by negative mutations in keratin-5 and keratin-14, proteins expressed in the intermediate filaments of basal keratinocytes, which result in fragility of the skin in response to minor trauma.² The incidence of EBS-loc is approximately 10 to 30 cases per million live births, with the age of presentation typically between the first and third decades of life.^3,4 Because EBS-loc is the most common and often mildest form of EB, not all patients present for medical evaluation and true prevalence may be underestimated.⁴ We report a case of EBS-loc.

A 26-year-old woman with no notable medical history presented to the dermatology clinic for evaluation of skin blisters that had been intermittently present since infancy. The blisters primarily occurred on the feet, but she did occasionally develop blisters on the hands, knees, and elbows and at sites of friction or trauma (eg, bra line, medial thighs) following exercise. The blisters were worsened by heat and tight-fitting shoes. Because of the painful nature of the blisters, she would lance them with a needle. On the medial thighs, she utilized nonstick and gauze bandage roll dressings to minimize friction. A review of systems was positive for hyperhidrosis. Her family history revealed multiple family members with blisters involving the feet and areas of friction or trauma for 4 generations with no known diagnosis.

Physical examination revealed multiple tense bullae and calluses scattered over the bilateral plantar and distal dorsal feet with a few healing, superficially eroded, erythematous papules and plaques on the bilateral medial thighs (Figure 1). A biopsy from an induced blister on the right dorsal second toe was performed and sent in glutaraldehyde to the Epidermolysis Bullosa Clinic at Stanford University (Redwood City, California) for electron microscopy, which revealed lysis within the basal keratinocytes through the tonofilaments with continuous and intact lamina densa and lamina lucida (Figure 2). In this clinical context with the relevant family history, the findings were consistent with the diagnosis of EBS-loc (formerly Weber-Cockayne syndrome).²

Light microscopy does not have a notable role in diagnosis of classic forms of inherited EB unless another autoimmune blistering disorder is suspected.^2,5 Both TEM and immunofluorescence mapping are used to diagnose EB.¹ DNA mutational analysis is not considered a first-line diagnostic test for EB given it is a costly labor-intensive technique with limited access at present, but it may be considered in settings of prenatal diagnosis or in vitro fertilization.¹ Biopsy of a freshly induced blister should be performed, as early reepithelialization of an existing blister makes it difficult to establish the level of cleavage.⁵ Applying firm pressure using a pencil eraser and rotating it on intact skin induces a subclinical blister. Two punch biopsies (4 mm) at the edge of the blister with one-third lesional and two-thirds perilesional skin should be obtained, with one biopsy sent for immunofluorescence mapping in Michel fixative and the other for TEM in glutaraldehyde.^3,5 Transmission electron microscopy of an induced blister in EBS-loc shows cleavage within the most inferior portion of the basilar keratinocyte.² Immunofluorescence mapping with anti–epidermal basement membrane monoclonal antibodies can distinguish between EB subtypes and assess expression of specific skin-associated proteins on both a qualitative or semiquantitative basis, providing insight on which structural protein is mutated.^1,5

No specific treatments are available for EBS-loc. Mainstays of treatment include prevention of mechanical trauma and secondary infection. Hyperhidrosis of thepalms and soles may be treated with topical aluminum chloride hexahydrate or injections of botulinum toxin type A.^2,6 Patients have normal life expectancy, though some cases may have complications with substantial morbidity.¹ Awareness of this disease, its clinical course, and therapeutic options will allow physicians to more appropriately counsel patients on the disease process.

Localized EBS may be more common than previously thought, as not all patients seek medical care. Given its impact on patient quality of life, it is important for clinicians to recognize EBS-loc. Although no specific treatments are available, wound care counseling and explanation of the genetics of the disease should be provided to patients.

To the Editor:

Epidermolysis bullosa (EB) was first described in 1886, with the first classification scheme proposed in 1962 utilizing transmission electron microscopy (TEM) findings to delineate categories: epidermolytic (EB simplex [EBS]), lucidolytic (junctional EB), and dermolytic (dystrophic EB).¹ Localized EBS (EBS-loc) is an autosomal-dominant disorder caused by negative mutations in keratin-5 and keratin-14, proteins expressed in the intermediate filaments of basal keratinocytes, which result in fragility of the skin in response to minor trauma.² The incidence of EBS-loc is approximately 10 to 30 cases per million live births, with the age of presentation typically between the first and third decades of life.^3,4 Because EBS-loc is the most common and often mildest form of EB, not all patients present for medical evaluation and true prevalence may be underestimated.⁴ We report a case of EBS-loc.

A 26-year-old woman with no notable medical history presented to the dermatology clinic for evaluation of skin blisters that had been intermittently present since infancy. The blisters primarily occurred on the feet, but she did occasionally develop blisters on the hands, knees, and elbows and at sites of friction or trauma (eg, bra line, medial thighs) following exercise. The blisters were worsened by heat and tight-fitting shoes. Because of the painful nature of the blisters, she would lance them with a needle. On the medial thighs, she utilized nonstick and gauze bandage roll dressings to minimize friction. A review of systems was positive for hyperhidrosis. Her family history revealed multiple family members with blisters involving the feet and areas of friction or trauma for 4 generations with no known diagnosis.

Physical examination revealed multiple tense bullae and calluses scattered over the bilateral plantar and distal dorsal feet with a few healing, superficially eroded, erythematous papules and plaques on the bilateral medial thighs (Figure 1). A biopsy from an induced blister on the right dorsal second toe was performed and sent in glutaraldehyde to the Epidermolysis Bullosa Clinic at Stanford University (Redwood City, California) for electron microscopy, which revealed lysis within the basal keratinocytes through the tonofilaments with continuous and intact lamina densa and lamina lucida (Figure 2). In this clinical context with the relevant family history, the findings were consistent with the diagnosis of EBS-loc (formerly Weber-Cockayne syndrome).²

Light microscopy does not have a notable role in diagnosis of classic forms of inherited EB unless another autoimmune blistering disorder is suspected.^2,5 Both TEM and immunofluorescence mapping are used to diagnose EB.¹ DNA mutational analysis is not considered a first-line diagnostic test for EB given it is a costly labor-intensive technique with limited access at present, but it may be considered in settings of prenatal diagnosis or in vitro fertilization.¹ Biopsy of a freshly induced blister should be performed, as early reepithelialization of an existing blister makes it difficult to establish the level of cleavage.⁵ Applying firm pressure using a pencil eraser and rotating it on intact skin induces a subclinical blister. Two punch biopsies (4 mm) at the edge of the blister with one-third lesional and two-thirds perilesional skin should be obtained, with one biopsy sent for immunofluorescence mapping in Michel fixative and the other for TEM in glutaraldehyde.^3,5 Transmission electron microscopy of an induced blister in EBS-loc shows cleavage within the most inferior portion of the basilar keratinocyte.² Immunofluorescence mapping with anti–epidermal basement membrane monoclonal antibodies can distinguish between EB subtypes and assess expression of specific skin-associated proteins on both a qualitative or semiquantitative basis, providing insight on which structural protein is mutated.^1,5

No specific treatments are available for EBS-loc. Mainstays of treatment include prevention of mechanical trauma and secondary infection. Hyperhidrosis of thepalms and soles may be treated with topical aluminum chloride hexahydrate or injections of botulinum toxin type A.^2,6 Patients have normal life expectancy, though some cases may have complications with substantial morbidity.¹ Awareness of this disease, its clinical course, and therapeutic options will allow physicians to more appropriately counsel patients on the disease process.

Localized EBS may be more common than previously thought, as not all patients seek medical care. Given its impact on patient quality of life, it is important for clinicians to recognize EBS-loc. Although no specific treatments are available, wound care counseling and explanation of the genetics of the disease should be provided to patients.

To the Editor:

The tongue is composed of 4 different types of papillae: fungiform, foliate, circumvallate, and filiform. Fungiform papillae, primarily located on the tip and sides of the tongue, are mushroom-shaped epithelial elevations composed of taste buds at the upper surface overlying a core of connective tissue.¹ Foliate and circumvallate papillae are likewise associated with taste buds, while the filiform papillae are hypothesized to exclusively provide a frictional surface for proper food manipulation. Pigmented fungiform papillae of the tongue (PFPT) was first reported by Leonard² in 1905, who described discrete hyperpigmentation present only on the surface of fungiform papillae, mainly in black patients. Although they have been primarily described in black individuals, PFPT also has been occasionally reported in Asian and Middle Eastern individuals as well as Indian women.^3-6

A 36-year-old Indian man initially presented to his primary care provider with brown discoloration of the dorsolateral aspects of the tongue that had been present since childhood. His primary care provider was concerned about a potential syndrome or systemic illness and referred the patient to dermatology for further evaluation. The patient denied any oral mucosal bleeding or discomfort, and a review of systems was unremarkable. His medical and family history were otherwise noncontributory, and he denied a history of tobacco use.

Physical examination of the tongue and oral mucosa revealed numerous 0.5- to 1.0-mm brown papillae in a symmetric distribution, primarily located on the tip and lateral aspects of the tongue (Figure). No hyperpigmentation was present on the posterior aspect of the tongue or on any other mucosal surface. Routine laboratory values were notable for mild elevations in aspartate aminotransferase and alanine aminotransferase (47 U/L [reference range, 10–30 U/L] and 64 U/L [reference range, 10–40 U/L], respectively) and mild hyperbilirubinemia (total bilirubin, 1.8 mg/dL [reference range, 0.3–1.2 mg/dL]). A complete blood cell count and electrolytes were within reference range. Based on the clinical appearance of the lesions and their presence since childhood, the patient was diagnosed with PFPT. No intervention was undertaken, and the patient was reassured of the benign nature of the lesions.

Pigmented fungiform papillae of the tongue presents in 3 variants. The first variant involves hyperpigmentation of all fungiform papillae located on the lateral and frontal aspects of the tongue and is the most common manifestation of PFPT.³ Our patient falls into this category. The second and third variants involve the dorsal surface, with the former involving only a few fungiform papillae on the dorsal aspect of the tongue and the latter variant involving all papillae.³ In 1974, Holzwanger et al³ conducted a survey of 300 random individuals, finding that 30% of black women and 25% of black men had some hyperpigmentation of the tongue, while only 1 white individual demonstrated lingual pigmentation. The physiology of PFPT remains largely unknown. Dermoscopic evaluation often demonstrates elevations with pigmented borders in a rose petal shape.⁷ Histopathologic evaluation reveals melanophages without inflammation that are positive for melanin on Fontana-Masson silver staining but negative for iron on Prussian blue staining.⁸

Despite the fact that PFPT is not a rare condition, the diagnosis remains notably missing from many standard dermatology textbooks and online dermatology resources, making it a potentially overlooked clinical entity.^4-6 The tongue has a number of normal variations that are unlikely to be fully appreciated or acknowledged by dermatologists on routine physical examination but may cause distress to patients and raise concerns from primary care providers. Given that PFPT are benign, physicians should be aware of this diagnosis so as to provide reassurance to patients and avoid unnecessary testing. However, because the tongue can represent a harbinger of systemic disease, the differential diagnosis for the hyperpigmented lesions must always be considered, including Peutz-Jeghers syndrome, hemochromatosis, Addison disease, and Laugier-Hunziker syndrome (a rarer condition causing pigmented lesions on the lips, palate, and tongue), particularly if the hyperpigmented lesions extend beyond the fungiform papillae and do not fit into the 3 categories of PFPT.⁹

To the Editor:

The tongue is composed of 4 different types of papillae: fungiform, foliate, circumvallate, and filiform. Fungiform papillae, primarily located on the tip and sides of the tongue, are mushroom-shaped epithelial elevations composed of taste buds at the upper surface overlying a core of connective tissue.¹ Foliate and circumvallate papillae are likewise associated with taste buds, while the filiform papillae are hypothesized to exclusively provide a frictional surface for proper food manipulation. Pigmented fungiform papillae of the tongue (PFPT) was first reported by Leonard² in 1905, who described discrete hyperpigmentation present only on the surface of fungiform papillae, mainly in black patients. Although they have been primarily described in black individuals, PFPT also has been occasionally reported in Asian and Middle Eastern individuals as well as Indian women.^3-6

A 36-year-old Indian man initially presented to his primary care provider with brown discoloration of the dorsolateral aspects of the tongue that had been present since childhood. His primary care provider was concerned about a potential syndrome or systemic illness and referred the patient to dermatology for further evaluation. The patient denied any oral mucosal bleeding or discomfort, and a review of systems was unremarkable. His medical and family history were otherwise noncontributory, and he denied a history of tobacco use.

Physical examination of the tongue and oral mucosa revealed numerous 0.5- to 1.0-mm brown papillae in a symmetric distribution, primarily located on the tip and lateral aspects of the tongue (Figure). No hyperpigmentation was present on the posterior aspect of the tongue or on any other mucosal surface. Routine laboratory values were notable for mild elevations in aspartate aminotransferase and alanine aminotransferase (47 U/L [reference range, 10–30 U/L] and 64 U/L [reference range, 10–40 U/L], respectively) and mild hyperbilirubinemia (total bilirubin, 1.8 mg/dL [reference range, 0.3–1.2 mg/dL]). A complete blood cell count and electrolytes were within reference range. Based on the clinical appearance of the lesions and their presence since childhood, the patient was diagnosed with PFPT. No intervention was undertaken, and the patient was reassured of the benign nature of the lesions.

Pigmented fungiform papillae of the tongue presents in 3 variants. The first variant involves hyperpigmentation of all fungiform papillae located on the lateral and frontal aspects of the tongue and is the most common manifestation of PFPT.³ Our patient falls into this category. The second and third variants involve the dorsal surface, with the former involving only a few fungiform papillae on the dorsal aspect of the tongue and the latter variant involving all papillae.³ In 1974, Holzwanger et al³ conducted a survey of 300 random individuals, finding that 30% of black women and 25% of black men had some hyperpigmentation of the tongue, while only 1 white individual demonstrated lingual pigmentation. The physiology of PFPT remains largely unknown. Dermoscopic evaluation often demonstrates elevations with pigmented borders in a rose petal shape.⁷ Histopathologic evaluation reveals melanophages without inflammation that are positive for melanin on Fontana-Masson silver staining but negative for iron on Prussian blue staining.⁸

Despite the fact that PFPT is not a rare condition, the diagnosis remains notably missing from many standard dermatology textbooks and online dermatology resources, making it a potentially overlooked clinical entity.^4-6 The tongue has a number of normal variations that are unlikely to be fully appreciated or acknowledged by dermatologists on routine physical examination but may cause distress to patients and raise concerns from primary care providers. Given that PFPT are benign, physicians should be aware of this diagnosis so as to provide reassurance to patients and avoid unnecessary testing. However, because the tongue can represent a harbinger of systemic disease, the differential diagnosis for the hyperpigmented lesions must always be considered, including Peutz-Jeghers syndrome, hemochromatosis, Addison disease, and Laugier-Hunziker syndrome (a rarer condition causing pigmented lesions on the lips, palate, and tongue), particularly if the hyperpigmented lesions extend beyond the fungiform papillae and do not fit into the 3 categories of PFPT.⁹

To the Editor:

The tongue is composed of 4 different types of papillae: fungiform, foliate, circumvallate, and filiform. Fungiform papillae, primarily located on the tip and sides of the tongue, are mushroom-shaped epithelial elevations composed of taste buds at the upper surface overlying a core of connective tissue.¹ Foliate and circumvallate papillae are likewise associated with taste buds, while the filiform papillae are hypothesized to exclusively provide a frictional surface for proper food manipulation. Pigmented fungiform papillae of the tongue (PFPT) was first reported by Leonard² in 1905, who described discrete hyperpigmentation present only on the surface of fungiform papillae, mainly in black patients. Although they have been primarily described in black individuals, PFPT also has been occasionally reported in Asian and Middle Eastern individuals as well as Indian women.^3-6

A 36-year-old Indian man initially presented to his primary care provider with brown discoloration of the dorsolateral aspects of the tongue that had been present since childhood. His primary care provider was concerned about a potential syndrome or systemic illness and referred the patient to dermatology for further evaluation. The patient denied any oral mucosal bleeding or discomfort, and a review of systems was unremarkable. His medical and family history were otherwise noncontributory, and he denied a history of tobacco use.

Physical examination of the tongue and oral mucosa revealed numerous 0.5- to 1.0-mm brown papillae in a symmetric distribution, primarily located on the tip and lateral aspects of the tongue (Figure). No hyperpigmentation was present on the posterior aspect of the tongue or on any other mucosal surface. Routine laboratory values were notable for mild elevations in aspartate aminotransferase and alanine aminotransferase (47 U/L [reference range, 10–30 U/L] and 64 U/L [reference range, 10–40 U/L], respectively) and mild hyperbilirubinemia (total bilirubin, 1.8 mg/dL [reference range, 0.3–1.2 mg/dL]). A complete blood cell count and electrolytes were within reference range. Based on the clinical appearance of the lesions and their presence since childhood, the patient was diagnosed with PFPT. No intervention was undertaken, and the patient was reassured of the benign nature of the lesions.

Pigmented fungiform papillae of the tongue presents in 3 variants. The first variant involves hyperpigmentation of all fungiform papillae located on the lateral and frontal aspects of the tongue and is the most common manifestation of PFPT.³ Our patient falls into this category. The second and third variants involve the dorsal surface, with the former involving only a few fungiform papillae on the dorsal aspect of the tongue and the latter variant involving all papillae.³ In 1974, Holzwanger et al³ conducted a survey of 300 random individuals, finding that 30% of black women and 25% of black men had some hyperpigmentation of the tongue, while only 1 white individual demonstrated lingual pigmentation. The physiology of PFPT remains largely unknown. Dermoscopic evaluation often demonstrates elevations with pigmented borders in a rose petal shape.⁷ Histopathologic evaluation reveals melanophages without inflammation that are positive for melanin on Fontana-Masson silver staining but negative for iron on Prussian blue staining.⁸

Despite the fact that PFPT is not a rare condition, the diagnosis remains notably missing from many standard dermatology textbooks and online dermatology resources, making it a potentially overlooked clinical entity.^4-6 The tongue has a number of normal variations that are unlikely to be fully appreciated or acknowledged by dermatologists on routine physical examination but may cause distress to patients and raise concerns from primary care providers. Given that PFPT are benign, physicians should be aware of this diagnosis so as to provide reassurance to patients and avoid unnecessary testing. However, because the tongue can represent a harbinger of systemic disease, the differential diagnosis for the hyperpigmented lesions must always be considered, including Peutz-Jeghers syndrome, hemochromatosis, Addison disease, and Laugier-Hunziker syndrome (a rarer condition causing pigmented lesions on the lips, palate, and tongue), particularly if the hyperpigmented lesions extend beyond the fungiform papillae and do not fit into the 3 categories of PFPT.⁹

To the Editor:

A 20-year-old man with no notable medical history presented to our dermatology clinic for evaluation of mildly painful, hemorrhagic bullae on the bilateral halluces of 1 month’s duration. On initial presentation the patient reported the lesions developed after wearing a new pair of tight-fitting shoes, suggesting a diagnosis of trauma-induced bullae. The patient was instructed to wear loose-fitting shoes and to follow up in 6 weeks to assess for improvement. At follow-up the bullae had resolved with residual violaceous patches on the bilateral distal halluces. He additionally developed a faint retiform erythematous patch on the left distal toe (Figure 1). The patient also had reticulate erythematous patches on the dorsal aspects of the hands extending to the forearms and legs resembling livedo reticularis. The patient was unsure if the skin lesions were triggered or worsened by cold exposure and reported that he smoked half a pack of cigarettes daily. At this time, the differential diagnosis still included trauma; however, there was concern for either embolic, thrombotic, or connective-tissue disease. A 4-mm punch biopsy of the left distal hallux demonstrated basal vacuolar interface dermatitis with superficial and deep perivascular inflammation and deep periadnexal mucin deposition (Figure 2) consistent with lupus dermatitis.

Serologic workup revealed increased antinuclear antibody titers of 1:320 (reference range, <1:40) and anti-Ro/Sjögren syndrome antigen antibodies of 86 (reference range, <20). There was no elevation in anti–double-stranded DNA, anti-Smith, antiribonucleoprotein, or anticardiolipin antibodies. Complement levels also were within reference range. Furthermore, the patient denied a history of Raynaud phenomenon, photosensitivity, oral ulcers, joint pain, shortness of breath, pleuritic chest pain, arthritis, blood clots, or any other systemic symptoms. Additional evaluation by the rheumatology department did not support criteria for systemic lupus erythematosus (SLE). In the context of the clinical presentation, histologic findings, and serologic markers, a diagnosis of chilblain lupus erythematosus (CHLE) was made. He was counseled on sun protection and smoking cessation and declined systemic therapy citing concern for side effects. Follow-up with the dermatology and rheumatology departments was advised.

Cutaneous lupus erythematosus (CLE) comprises various forms of lupus, including acute cutaneous lupus, subacute cutaneous lupus, and chronic cutaneous lupus. Chilblain lupus erythematosus is a rare subset of chronic CLE that first was described in 1888¹ and is characterized by tender violaceous papules and plaques that typically present in an acral distribution (ie, fingers, toes, nose, cheeks, ears). The skin lesions often are triggered or exacerbated by cold temperatures and dampness. As the lesions evolve, they can ulcerate, fissure, become hyperkeratotic, or result in atrophic plaques with scarring.^2,3 A subset of patients also may have concurrent Raynaud phenomenon.¹ Up to 20% of patients will eventually develop SLE, especially those patients with concurrent discoid lupus erythematosus, warranting close long-term follow-up.³ Serologic studies can reveal antinuclear antibodies, anti-Ro/Sjögren syndrome antigen antibodies, rheumatic factor, and anti–double-stranded DNA antibodies.^1,4 Hypergammaglobulinemia also is a common finding in patients with CHLE, affecting more than two-thirds of patients.¹ Typical features of CHLE seen on histopathology include interface dermatitis, perivascular lymphocytic infiltrate, apoptotic keratinocytes, lichenoid tissue reaction, and increased dermal mucin.^1,4

Chilblain lupus erythematosus most commonly presents sporadically; however, there is a familial form that has been previously described.⁵ Sporadic CHLE usually occurs in middle-aged females, in contrast to familial CHLE, which presents in early childhood.¹ The pathogenesis of the sporadic form is poorly understood, but it is thought to be stimulated by vasoconstriction or microvascular injury provoked by cold exposure. Furthermore, hypergammaglobulinemia and the presence of autoantibodies may contribute to the pathogenesis by increasing blood viscosity.¹ The familial form is caused by heterozygous mutations in either TREX1, a gene encoding the 3′ to 5′ repair exonuclease 1, or SAMHD1, the gene encoding for SAM domain and HD domain 1. TREX1 is an intracellular deoxyribonuclease that has specificity for single-stranded DNA. It is hypothesized that a deficiency in TREX1 leads to the accumulation of nucleic acids, which activate innate immune sensors and lead to a type I interferon response that favors the development of autoimmunity.⁵

Several drugs including thiazides, terbinafine, calcium channel blockers, angiotensin-converting enzyme inhibitors, and chemotherapeutic agents have been reported to trigger CHLE.⁴ Tumor necrosis factor α inhibitors have been shown to precipitate CHLE.⁶ Of note, drug-induced CHLE usually is limited to the skin and has not been shown to progress to SLE.⁶ Lebeau et al⁴ described a patient with breast cancer and preexisting CHLE that flared while the patient received docetaxel therapy, suggesting that certain drugs may not only induce but also may aggravate CHLE.

Many of the therapies that are effective in SLE such as antimalarial agents (ie, chloroquine, hydroxychloroquine) often are less efficacious in treating the lesions of CHLE.¹ However, these patients often can be managed successfully by physical protection from the cold environment.¹ Calcium channel blockers such as nifedipine also have been implicated, as they counteract vasoconstriction, which is thought to contribute to the pathogenesis of CHLE.¹ Topical and systemic steroids also have been used to treat CHLE. Dapsone and pentoxifylline are other treatment modalities that have been effective in select cases of CHLE.⁵ Boehm and Bieber⁷ reported near resolution of CHLE with mycophenolate mofetil in an elderly woman with skin lesions that had been refractory to systemic steroids, antimalarial agents, azathioprine, dapsone, and pentoxifylline, suggesting that mycophenolate mofetil may be a therapeutic option for recalcitrant cases of CHLE. Local immunosuppressive agents such as tacrolimus also can be considered in treatment-refractory disease.

Chilblain lupus erythematosus is a rare chronic form of CLE that typically occurs sporadically but also has a familial form that has been described in several families. It most commonly is observed in middle-aged women, but we describe a case in a young man. Although CHLE typically does not respond well to traditional lupus therapies used in the management of SLE, good effects have been observed with cold avoidance, calcium channel blockers, and topical or oral steroids. For treatment-refractory cases, mycophenolate mofetil and other immunosuppressive agents have been shown to be effective.

To the Editor:

A 20-year-old man with no notable medical history presented to our dermatology clinic for evaluation of mildly painful, hemorrhagic bullae on the bilateral halluces of 1 month’s duration. On initial presentation the patient reported the lesions developed after wearing a new pair of tight-fitting shoes, suggesting a diagnosis of trauma-induced bullae. The patient was instructed to wear loose-fitting shoes and to follow up in 6 weeks to assess for improvement. At follow-up the bullae had resolved with residual violaceous patches on the bilateral distal halluces. He additionally developed a faint retiform erythematous patch on the left distal toe (Figure 1). The patient also had reticulate erythematous patches on the dorsal aspects of the hands extending to the forearms and legs resembling livedo reticularis. The patient was unsure if the skin lesions were triggered or worsened by cold exposure and reported that he smoked half a pack of cigarettes daily. At this time, the differential diagnosis still included trauma; however, there was concern for either embolic, thrombotic, or connective-tissue disease. A 4-mm punch biopsy of the left distal hallux demonstrated basal vacuolar interface dermatitis with superficial and deep perivascular inflammation and deep periadnexal mucin deposition (Figure 2) consistent with lupus dermatitis.

Serologic workup revealed increased antinuclear antibody titers of 1:320 (reference range, <1:40) and anti-Ro/Sjögren syndrome antigen antibodies of 86 (reference range, <20). There was no elevation in anti–double-stranded DNA, anti-Smith, antiribonucleoprotein, or anticardiolipin antibodies. Complement levels also were within reference range. Furthermore, the patient denied a history of Raynaud phenomenon, photosensitivity, oral ulcers, joint pain, shortness of breath, pleuritic chest pain, arthritis, blood clots, or any other systemic symptoms. Additional evaluation by the rheumatology department did not support criteria for systemic lupus erythematosus (SLE). In the context of the clinical presentation, histologic findings, and serologic markers, a diagnosis of chilblain lupus erythematosus (CHLE) was made. He was counseled on sun protection and smoking cessation and declined systemic therapy citing concern for side effects. Follow-up with the dermatology and rheumatology departments was advised.

Cutaneous lupus erythematosus (CLE) comprises various forms of lupus, including acute cutaneous lupus, subacute cutaneous lupus, and chronic cutaneous lupus. Chilblain lupus erythematosus is a rare subset of chronic CLE that first was described in 1888¹ and is characterized by tender violaceous papules and plaques that typically present in an acral distribution (ie, fingers, toes, nose, cheeks, ears). The skin lesions often are triggered or exacerbated by cold temperatures and dampness. As the lesions evolve, they can ulcerate, fissure, become hyperkeratotic, or result in atrophic plaques with scarring.^2,3 A subset of patients also may have concurrent Raynaud phenomenon.¹ Up to 20% of patients will eventually develop SLE, especially those patients with concurrent discoid lupus erythematosus, warranting close long-term follow-up.³ Serologic studies can reveal antinuclear antibodies, anti-Ro/Sjögren syndrome antigen antibodies, rheumatic factor, and anti–double-stranded DNA antibodies.^1,4 Hypergammaglobulinemia also is a common finding in patients with CHLE, affecting more than two-thirds of patients.¹ Typical features of CHLE seen on histopathology include interface dermatitis, perivascular lymphocytic infiltrate, apoptotic keratinocytes, lichenoid tissue reaction, and increased dermal mucin.^1,4

Chilblain lupus erythematosus most commonly presents sporadically; however, there is a familial form that has been previously described.⁵ Sporadic CHLE usually occurs in middle-aged females, in contrast to familial CHLE, which presents in early childhood.¹ The pathogenesis of the sporadic form is poorly understood, but it is thought to be stimulated by vasoconstriction or microvascular injury provoked by cold exposure. Furthermore, hypergammaglobulinemia and the presence of autoantibodies may contribute to the pathogenesis by increasing blood viscosity.¹ The familial form is caused by heterozygous mutations in either TREX1, a gene encoding the 3′ to 5′ repair exonuclease 1, or SAMHD1, the gene encoding for SAM domain and HD domain 1. TREX1 is an intracellular deoxyribonuclease that has specificity for single-stranded DNA. It is hypothesized that a deficiency in TREX1 leads to the accumulation of nucleic acids, which activate innate immune sensors and lead to a type I interferon response that favors the development of autoimmunity.⁵

Several drugs including thiazides, terbinafine, calcium channel blockers, angiotensin-converting enzyme inhibitors, and chemotherapeutic agents have been reported to trigger CHLE.⁴ Tumor necrosis factor α inhibitors have been shown to precipitate CHLE.⁶ Of note, drug-induced CHLE usually is limited to the skin and has not been shown to progress to SLE.⁶ Lebeau et al⁴ described a patient with breast cancer and preexisting CHLE that flared while the patient received docetaxel therapy, suggesting that certain drugs may not only induce but also may aggravate CHLE.

Many of the therapies that are effective in SLE such as antimalarial agents (ie, chloroquine, hydroxychloroquine) often are less efficacious in treating the lesions of CHLE.¹ However, these patients often can be managed successfully by physical protection from the cold environment.¹ Calcium channel blockers such as nifedipine also have been implicated, as they counteract vasoconstriction, which is thought to contribute to the pathogenesis of CHLE.¹ Topical and systemic steroids also have been used to treat CHLE. Dapsone and pentoxifylline are other treatment modalities that have been effective in select cases of CHLE.⁵ Boehm and Bieber⁷ reported near resolution of CHLE with mycophenolate mofetil in an elderly woman with skin lesions that had been refractory to systemic steroids, antimalarial agents, azathioprine, dapsone, and pentoxifylline, suggesting that mycophenolate mofetil may be a therapeutic option for recalcitrant cases of CHLE. Local immunosuppressive agents such as tacrolimus also can be considered in treatment-refractory disease.

Chilblain lupus erythematosus is a rare chronic form of CLE that typically occurs sporadically but also has a familial form that has been described in several families. It most commonly is observed in middle-aged women, but we describe a case in a young man. Although CHLE typically does not respond well to traditional lupus therapies used in the management of SLE, good effects have been observed with cold avoidance, calcium channel blockers, and topical or oral steroids. For treatment-refractory cases, mycophenolate mofetil and other immunosuppressive agents have been shown to be effective.

To the Editor:

A 20-year-old man with no notable medical history presented to our dermatology clinic for evaluation of mildly painful, hemorrhagic bullae on the bilateral halluces of 1 month’s duration. On initial presentation the patient reported the lesions developed after wearing a new pair of tight-fitting shoes, suggesting a diagnosis of trauma-induced bullae. The patient was instructed to wear loose-fitting shoes and to follow up in 6 weeks to assess for improvement. At follow-up the bullae had resolved with residual violaceous patches on the bilateral distal halluces. He additionally developed a faint retiform erythematous patch on the left distal toe (Figure 1). The patient also had reticulate erythematous patches on the dorsal aspects of the hands extending to the forearms and legs resembling livedo reticularis. The patient was unsure if the skin lesions were triggered or worsened by cold exposure and reported that he smoked half a pack of cigarettes daily. At this time, the differential diagnosis still included trauma; however, there was concern for either embolic, thrombotic, or connective-tissue disease. A 4-mm punch biopsy of the left distal hallux demonstrated basal vacuolar interface dermatitis with superficial and deep perivascular inflammation and deep periadnexal mucin deposition (Figure 2) consistent with lupus dermatitis.

Serologic workup revealed increased antinuclear antibody titers of 1:320 (reference range, <1:40) and anti-Ro/Sjögren syndrome antigen antibodies of 86 (reference range, <20). There was no elevation in anti–double-stranded DNA, anti-Smith, antiribonucleoprotein, or anticardiolipin antibodies. Complement levels also were within reference range. Furthermore, the patient denied a history of Raynaud phenomenon, photosensitivity, oral ulcers, joint pain, shortness of breath, pleuritic chest pain, arthritis, blood clots, or any other systemic symptoms. Additional evaluation by the rheumatology department did not support criteria for systemic lupus erythematosus (SLE). In the context of the clinical presentation, histologic findings, and serologic markers, a diagnosis of chilblain lupus erythematosus (CHLE) was made. He was counseled on sun protection and smoking cessation and declined systemic therapy citing concern for side effects. Follow-up with the dermatology and rheumatology departments was advised.

Cutaneous lupus erythematosus (CLE) comprises various forms of lupus, including acute cutaneous lupus, subacute cutaneous lupus, and chronic cutaneous lupus. Chilblain lupus erythematosus is a rare subset of chronic CLE that first was described in 1888¹ and is characterized by tender violaceous papules and plaques that typically present in an acral distribution (ie, fingers, toes, nose, cheeks, ears). The skin lesions often are triggered or exacerbated by cold temperatures and dampness. As the lesions evolve, they can ulcerate, fissure, become hyperkeratotic, or result in atrophic plaques with scarring.^2,3 A subset of patients also may have concurrent Raynaud phenomenon.¹ Up to 20% of patients will eventually develop SLE, especially those patients with concurrent discoid lupus erythematosus, warranting close long-term follow-up.³ Serologic studies can reveal antinuclear antibodies, anti-Ro/Sjögren syndrome antigen antibodies, rheumatic factor, and anti–double-stranded DNA antibodies.^1,4 Hypergammaglobulinemia also is a common finding in patients with CHLE, affecting more than two-thirds of patients.¹ Typical features of CHLE seen on histopathology include interface dermatitis, perivascular lymphocytic infiltrate, apoptotic keratinocytes, lichenoid tissue reaction, and increased dermal mucin.^1,4

Chilblain lupus erythematosus most commonly presents sporadically; however, there is a familial form that has been previously described.⁵ Sporadic CHLE usually occurs in middle-aged females, in contrast to familial CHLE, which presents in early childhood.¹ The pathogenesis of the sporadic form is poorly understood, but it is thought to be stimulated by vasoconstriction or microvascular injury provoked by cold exposure. Furthermore, hypergammaglobulinemia and the presence of autoantibodies may contribute to the pathogenesis by increasing blood viscosity.¹ The familial form is caused by heterozygous mutations in either TREX1, a gene encoding the 3′ to 5′ repair exonuclease 1, or SAMHD1, the gene encoding for SAM domain and HD domain 1. TREX1 is an intracellular deoxyribonuclease that has specificity for single-stranded DNA. It is hypothesized that a deficiency in TREX1 leads to the accumulation of nucleic acids, which activate innate immune sensors and lead to a type I interferon response that favors the development of autoimmunity.⁵

Several drugs including thiazides, terbinafine, calcium channel blockers, angiotensin-converting enzyme inhibitors, and chemotherapeutic agents have been reported to trigger CHLE.⁴ Tumor necrosis factor α inhibitors have been shown to precipitate CHLE.⁶ Of note, drug-induced CHLE usually is limited to the skin and has not been shown to progress to SLE.⁶ Lebeau et al⁴ described a patient with breast cancer and preexisting CHLE that flared while the patient received docetaxel therapy, suggesting that certain drugs may not only induce but also may aggravate CHLE.

Many of the therapies that are effective in SLE such as antimalarial agents (ie, chloroquine, hydroxychloroquine) often are less efficacious in treating the lesions of CHLE.¹ However, these patients often can be managed successfully by physical protection from the cold environment.¹ Calcium channel blockers such as nifedipine also have been implicated, as they counteract vasoconstriction, which is thought to contribute to the pathogenesis of CHLE.¹ Topical and systemic steroids also have been used to treat CHLE. Dapsone and pentoxifylline are other treatment modalities that have been effective in select cases of CHLE.⁵ Boehm and Bieber⁷ reported near resolution of CHLE with mycophenolate mofetil in an elderly woman with skin lesions that had been refractory to systemic steroids, antimalarial agents, azathioprine, dapsone, and pentoxifylline, suggesting that mycophenolate mofetil may be a therapeutic option for recalcitrant cases of CHLE. Local immunosuppressive agents such as tacrolimus also can be considered in treatment-refractory disease.

Chilblain lupus erythematosus is a rare chronic form of CLE that typically occurs sporadically but also has a familial form that has been described in several families. It most commonly is observed in middle-aged women, but we describe a case in a young man. Although CHLE typically does not respond well to traditional lupus therapies used in the management of SLE, good effects have been observed with cold avoidance, calcium channel blockers, and topical or oral steroids. For treatment-refractory cases, mycophenolate mofetil and other immunosuppressive agents have been shown to be effective.