Catalina Matiz, MD

Diagnosis

During the visit, skin scrapings were performed, revealing several Demodex mites, confirming the diagnosis of demodicosis.

Demodicosis refers to an infestation and sensitivity to Demodex spp. mites, usually in older adults or immunocompromised individuals. Demodex folliculorum and Demodex brevis are the two common species implicated. The life cycle of Demodex spp. occurs in the sebaceous glands, leading to mechanical and chemical irritation of the skin.

dibrulebethiphovecriuistikothihafriclavedribuhebrilecisurohodolashidroshedidraspifrodrislatidrihuwroswikiphadruchisubujire

Various immune responses are also triggered, such as a keratinocyte response via Toll-like receptor 2. Patients usually present with non-specific symptoms such as skin erythema, irritation, peeling, and dryness on the cheeks, eyelids, and paranasal areas. Patients may develop a maculopapular or rosacea-like rash.

Diagnosis is often made through microscopic examination of a skin sample in KOH solution. In rare occasions, a skin surface standardization biopsy method may be used, which determines the density of mites per 1 cm². Dermoscopy may identify spiky white structures. Molecular methods such as PCR can be used but are not standard.

Matiz_Catalina_SanDiego.jpg

The differential diagnosis may include acne, rosacea, folliculitis, and Candida infection. Demodicosis can be differentiated by history and further studies including dermoscopy.

Acne vulgaris is an inflammatory disease of the skin’s pilosebaceous unit, primarily involving the face and trunk. It can present with comedones, papules, pustules, and nodules. Secondary signs suggestive of acne vulgaris include scars, erythema, and hyperpigmentation. All forms of acne share a common pathogenesis resulting in the formation of microcomedones, precursors for all clinical acne lesions. In this patient, the absence of microcomedones and the presence of primary inflammatory papules localized to the nose and cheeks suggested an alternative diagnosis.

ribabocicriphiuujonahobarofredovecopegecludobriwikeclogolustotufrucluclephiwochameclewruwrecapalutupruclafruclovatehoclicinatuthabretropruliwrudrufronebrephujepephestuwidracimochanufracahalichelufreshiuasteninofrojutribrichedrasli

Rosacea was also considered in the differential diagnosis. Rosacea is an inflammatory dermatosis characterized by erythema, telangiectasia, recurrent flushing, and inflammatory lesions including papulopustules and swelling, primarily affecting the face. The pathogenesis of rosacea is not fully understood but is suggested to involve immune-mediated responses. Vascular dysregulation and reactive oxygen species damage keratinocytes, fibroblasts, and endothelial cells. A higher incidence of rosacea in those with a family history and UV exposure is a known trigger. Demodex folliculorum and Helicobacter pylori are also implicated. Occasionally, Demodex infestation and rosacea may co-occur, and treatment with topical metronidazole can be helpful.

Folliculitis is an infection and inflammation of the hair follicles, forming pustules or erythematous papules over hair-covered skin. It is commonly caused by bacterial infection but can also be due to fungi, viruses, and noninfectious causes such as eosinophilic folliculitis. Diagnosis is clinical, based on physical exam and history, such as recent increased sweating or scratching. KOH prep can be used for Malassezia folliculitis and skin biopsy for eosinophilic folliculitis. Treatment targets the underlying cause. Most bacterial folliculitis cases resolve without treatment, but topical antibiotics may be used. Fungal folliculitis requires oral antifungals, and herpes simplex folliculitis can be treated with antiviral medications.

Cutaneous candidiasis is an infection of the skin by various Candida species, commonly C. albicans. Superficial infections of the skin and mucous membranes, such as intertrigo, are common types. Risk factors include immunosuppression, endocrine disorders, or compromised blood flow. Increased humidity, occlusion, broken skin barriers, and altered skin microbial flora contribute to Candida infection. Diagnosis is clinical but can be confirmed by KOH prep, microscopy, and culture. Treatment involves anti-inflammatory, antibacterial, and antifungal medications. Topical clotrimazole, nystatin, and miconazole are commonly used. Recurrence is prevented by keeping the affected area dry with barrier creams.

Therapeutic goals include arresting mite reproduction, elimination, and preventing recurrent infestations. Treatment may last several months, and the choice of drug depends on patient factors. There have been no standardized treatment studies or long-term effectiveness analyses. Antibiotics such as tetracycline, metronidazole, doxycycline, and ivermectin may be used to prevent proliferation. Permethrin, benzyl benzoate, crotamiton, lindane, and sulfur have also been used. Metronidazole is a common treatment for demodicosis, as was used in our patient for several weeks until the lesions cleared. Systemic metronidazole therapy may be indicated for reducing Demodex spp. density. Severe cases, particularly in immunocompromised individuals, may require oral ivermectin. Appropriate hygiene is important for prevention, such as washing the face with non-oily cleansers and laundering linens regularly.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego. Mr. Lee is a medical student at the University of California San Diego.

Suggested Reading

Chudzicka-Strugała I et al. Demodicosis in different age groups and alternative treatment options—A review. J Clin Med. 2023 Feb 19;12(4):1649. doi: 10.3390/jcm12041649.

Eichenfield DZ et al. Management of acne vulgaris: A review. JAMA. 2021 Nov 23;326(20):2055-2067. doi: 10.1001/jama.2021.17633.

Sharma A et al. Rosacea management: A comprehensive review. J Cosmet Dermatol. 2022 May;21(5):1895-1904. doi: 10.1111/jocd.14816.

Taudorf EH et al. Cutaneous candidiasis — an evidence-based review of topical and systemic treatments to inform clinical practice. J Eur Acad Dermatol Venereol. 2019 Oct;33(10):1863-1873. doi: 10.1111/jdv.15782.

Winters RD, Mitchell M. Folliculitis. [Updated 2023 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024. Available from: https://www.ncbi.nlm.nih.gov/books/NBK547754/
 

Diagnosis

During the visit, skin scrapings were performed, revealing several Demodex mites, confirming the diagnosis of demodicosis.

Demodicosis refers to an infestation and sensitivity to Demodex spp. mites, usually in older adults or immunocompromised individuals. Demodex folliculorum and Demodex brevis are the two common species implicated. The life cycle of Demodex spp. occurs in the sebaceous glands, leading to mechanical and chemical irritation of the skin.

dibrulebethiphovecriuistikothihafriclavedribuhebrilecisurohodolashidroshedidraspifrodrislatidrihuwroswikiphadruchisubujire

Various immune responses are also triggered, such as a keratinocyte response via Toll-like receptor 2. Patients usually present with non-specific symptoms such as skin erythema, irritation, peeling, and dryness on the cheeks, eyelids, and paranasal areas. Patients may develop a maculopapular or rosacea-like rash.

Diagnosis is often made through microscopic examination of a skin sample in KOH solution. In rare occasions, a skin surface standardization biopsy method may be used, which determines the density of mites per 1 cm². Dermoscopy may identify spiky white structures. Molecular methods such as PCR can be used but are not standard.

Matiz_Catalina_SanDiego.jpg

The differential diagnosis may include acne, rosacea, folliculitis, and Candida infection. Demodicosis can be differentiated by history and further studies including dermoscopy.

Acne vulgaris is an inflammatory disease of the skin’s pilosebaceous unit, primarily involving the face and trunk. It can present with comedones, papules, pustules, and nodules. Secondary signs suggestive of acne vulgaris include scars, erythema, and hyperpigmentation. All forms of acne share a common pathogenesis resulting in the formation of microcomedones, precursors for all clinical acne lesions. In this patient, the absence of microcomedones and the presence of primary inflammatory papules localized to the nose and cheeks suggested an alternative diagnosis.

ribabocicriphiuujonahobarofredovecopegecludobriwikeclogolustotufrucluclephiwochameclewruwrecapalutupruclafruclovatehoclicinatuthabretropruliwrudrufronebrephujepephestuwidracimochanufracahalichelufreshiuasteninofrojutribrichedrasli

Rosacea was also considered in the differential diagnosis. Rosacea is an inflammatory dermatosis characterized by erythema, telangiectasia, recurrent flushing, and inflammatory lesions including papulopustules and swelling, primarily affecting the face. The pathogenesis of rosacea is not fully understood but is suggested to involve immune-mediated responses. Vascular dysregulation and reactive oxygen species damage keratinocytes, fibroblasts, and endothelial cells. A higher incidence of rosacea in those with a family history and UV exposure is a known trigger. Demodex folliculorum and Helicobacter pylori are also implicated. Occasionally, Demodex infestation and rosacea may co-occur, and treatment with topical metronidazole can be helpful.

Folliculitis is an infection and inflammation of the hair follicles, forming pustules or erythematous papules over hair-covered skin. It is commonly caused by bacterial infection but can also be due to fungi, viruses, and noninfectious causes such as eosinophilic folliculitis. Diagnosis is clinical, based on physical exam and history, such as recent increased sweating or scratching. KOH prep can be used for Malassezia folliculitis and skin biopsy for eosinophilic folliculitis. Treatment targets the underlying cause. Most bacterial folliculitis cases resolve without treatment, but topical antibiotics may be used. Fungal folliculitis requires oral antifungals, and herpes simplex folliculitis can be treated with antiviral medications.

Cutaneous candidiasis is an infection of the skin by various Candida species, commonly C. albicans. Superficial infections of the skin and mucous membranes, such as intertrigo, are common types. Risk factors include immunosuppression, endocrine disorders, or compromised blood flow. Increased humidity, occlusion, broken skin barriers, and altered skin microbial flora contribute to Candida infection. Diagnosis is clinical but can be confirmed by KOH prep, microscopy, and culture. Treatment involves anti-inflammatory, antibacterial, and antifungal medications. Topical clotrimazole, nystatin, and miconazole are commonly used. Recurrence is prevented by keeping the affected area dry with barrier creams.

Therapeutic goals include arresting mite reproduction, elimination, and preventing recurrent infestations. Treatment may last several months, and the choice of drug depends on patient factors. There have been no standardized treatment studies or long-term effectiveness analyses. Antibiotics such as tetracycline, metronidazole, doxycycline, and ivermectin may be used to prevent proliferation. Permethrin, benzyl benzoate, crotamiton, lindane, and sulfur have also been used. Metronidazole is a common treatment for demodicosis, as was used in our patient for several weeks until the lesions cleared. Systemic metronidazole therapy may be indicated for reducing Demodex spp. density. Severe cases, particularly in immunocompromised individuals, may require oral ivermectin. Appropriate hygiene is important for prevention, such as washing the face with non-oily cleansers and laundering linens regularly.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego. Mr. Lee is a medical student at the University of California San Diego.

Suggested Reading

Chudzicka-Strugała I et al. Demodicosis in different age groups and alternative treatment options—A review. J Clin Med. 2023 Feb 19;12(4):1649. doi: 10.3390/jcm12041649.

Eichenfield DZ et al. Management of acne vulgaris: A review. JAMA. 2021 Nov 23;326(20):2055-2067. doi: 10.1001/jama.2021.17633.

Sharma A et al. Rosacea management: A comprehensive review. J Cosmet Dermatol. 2022 May;21(5):1895-1904. doi: 10.1111/jocd.14816.

Taudorf EH et al. Cutaneous candidiasis — an evidence-based review of topical and systemic treatments to inform clinical practice. J Eur Acad Dermatol Venereol. 2019 Oct;33(10):1863-1873. doi: 10.1111/jdv.15782.

Winters RD, Mitchell M. Folliculitis. [Updated 2023 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024. Available from: https://www.ncbi.nlm.nih.gov/books/NBK547754/
 

Diagnosis

During the visit, skin scrapings were performed, revealing several Demodex mites, confirming the diagnosis of demodicosis.

Demodicosis refers to an infestation and sensitivity to Demodex spp. mites, usually in older adults or immunocompromised individuals. Demodex folliculorum and Demodex brevis are the two common species implicated. The life cycle of Demodex spp. occurs in the sebaceous glands, leading to mechanical and chemical irritation of the skin.

dibrulebethiphovecriuistikothihafriclavedribuhebrilecisurohodolashidroshedidraspifrodrislatidrihuwroswikiphadruchisubujire

Various immune responses are also triggered, such as a keratinocyte response via Toll-like receptor 2. Patients usually present with non-specific symptoms such as skin erythema, irritation, peeling, and dryness on the cheeks, eyelids, and paranasal areas. Patients may develop a maculopapular or rosacea-like rash.

Diagnosis is often made through microscopic examination of a skin sample in KOH solution. In rare occasions, a skin surface standardization biopsy method may be used, which determines the density of mites per 1 cm². Dermoscopy may identify spiky white structures. Molecular methods such as PCR can be used but are not standard.

Matiz_Catalina_SanDiego.jpg

The differential diagnosis may include acne, rosacea, folliculitis, and Candida infection. Demodicosis can be differentiated by history and further studies including dermoscopy.

Acne vulgaris is an inflammatory disease of the skin’s pilosebaceous unit, primarily involving the face and trunk. It can present with comedones, papules, pustules, and nodules. Secondary signs suggestive of acne vulgaris include scars, erythema, and hyperpigmentation. All forms of acne share a common pathogenesis resulting in the formation of microcomedones, precursors for all clinical acne lesions. In this patient, the absence of microcomedones and the presence of primary inflammatory papules localized to the nose and cheeks suggested an alternative diagnosis.

ribabocicriphiuujonahobarofredovecopegecludobriwikeclogolustotufrucluclephiwochameclewruwrecapalutupruclafruclovatehoclicinatuthabretropruliwrudrufronebrephujepephestuwidracimochanufracahalichelufreshiuasteninofrojutribrichedrasli

Rosacea was also considered in the differential diagnosis. Rosacea is an inflammatory dermatosis characterized by erythema, telangiectasia, recurrent flushing, and inflammatory lesions including papulopustules and swelling, primarily affecting the face. The pathogenesis of rosacea is not fully understood but is suggested to involve immune-mediated responses. Vascular dysregulation and reactive oxygen species damage keratinocytes, fibroblasts, and endothelial cells. A higher incidence of rosacea in those with a family history and UV exposure is a known trigger. Demodex folliculorum and Helicobacter pylori are also implicated. Occasionally, Demodex infestation and rosacea may co-occur, and treatment with topical metronidazole can be helpful.

Folliculitis is an infection and inflammation of the hair follicles, forming pustules or erythematous papules over hair-covered skin. It is commonly caused by bacterial infection but can also be due to fungi, viruses, and noninfectious causes such as eosinophilic folliculitis. Diagnosis is clinical, based on physical exam and history, such as recent increased sweating or scratching. KOH prep can be used for Malassezia folliculitis and skin biopsy for eosinophilic folliculitis. Treatment targets the underlying cause. Most bacterial folliculitis cases resolve without treatment, but topical antibiotics may be used. Fungal folliculitis requires oral antifungals, and herpes simplex folliculitis can be treated with antiviral medications.

Cutaneous candidiasis is an infection of the skin by various Candida species, commonly C. albicans. Superficial infections of the skin and mucous membranes, such as intertrigo, are common types. Risk factors include immunosuppression, endocrine disorders, or compromised blood flow. Increased humidity, occlusion, broken skin barriers, and altered skin microbial flora contribute to Candida infection. Diagnosis is clinical but can be confirmed by KOH prep, microscopy, and culture. Treatment involves anti-inflammatory, antibacterial, and antifungal medications. Topical clotrimazole, nystatin, and miconazole are commonly used. Recurrence is prevented by keeping the affected area dry with barrier creams.

Therapeutic goals include arresting mite reproduction, elimination, and preventing recurrent infestations. Treatment may last several months, and the choice of drug depends on patient factors. There have been no standardized treatment studies or long-term effectiveness analyses. Antibiotics such as tetracycline, metronidazole, doxycycline, and ivermectin may be used to prevent proliferation. Permethrin, benzyl benzoate, crotamiton, lindane, and sulfur have also been used. Metronidazole is a common treatment for demodicosis, as was used in our patient for several weeks until the lesions cleared. Systemic metronidazole therapy may be indicated for reducing Demodex spp. density. Severe cases, particularly in immunocompromised individuals, may require oral ivermectin. Appropriate hygiene is important for prevention, such as washing the face with non-oily cleansers and laundering linens regularly.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego. Mr. Lee is a medical student at the University of California San Diego.

Suggested Reading

Chudzicka-Strugała I et al. Demodicosis in different age groups and alternative treatment options—A review. J Clin Med. 2023 Feb 19;12(4):1649. doi: 10.3390/jcm12041649.

Eichenfield DZ et al. Management of acne vulgaris: A review. JAMA. 2021 Nov 23;326(20):2055-2067. doi: 10.1001/jama.2021.17633.

Sharma A et al. Rosacea management: A comprehensive review. J Cosmet Dermatol. 2022 May;21(5):1895-1904. doi: 10.1111/jocd.14816.

Taudorf EH et al. Cutaneous candidiasis — an evidence-based review of topical and systemic treatments to inform clinical practice. J Eur Acad Dermatol Venereol. 2019 Oct;33(10):1863-1873. doi: 10.1111/jdv.15782.

Winters RD, Mitchell M. Folliculitis. [Updated 2023 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024. Available from: https://www.ncbi.nlm.nih.gov/books/NBK547754/
 

KOH analysis of the scales from the scalp areas revealed no fungal elements. Given the observed erythema and scaling, a punch biopsy was conducted. Histopathological examination of the biopsy sample displayed interface inflammation affecting both the infundibular and lower portions of hair follicles. The presence of folliculosebaceous units transitioning from intermediate to terminal size follicles was noted. A perifollicular, peri eccrine, superficial, and deep perivascular lymphoplasmacytic infiltrate was identified, alongside increased dermal mucin, findings consistent with a diagnosis of discoid lupus erythematosus.

Subsequent laboratory investigations were largely unremarkable, except for an elevated ANA titer (1:320, with a speckled pattern). The patient was initiated on a treatment regimen comprising intralesional triamcinolone and oral hydroxychloroquine (Plaquenil).

167686_scalp1_web.jpg

Discussion

Pediatric discoid lupus erythematosus (DLE) is a rare but chronic autoimmune condition, representing one of the most prevalent forms of cutaneous lupus erythematosus. It predominantly affects adults, yet pediatric cases account for 5%-7% of DLE diagnoses, with a significant predominance in females. Pediatric scalp DLE is particularly concerning due to its potential for causing scarring and permanent hair loss, which can significantly impact the psychological wellbeing of affected children.

The pathogenesis of DLE is multifactorial, involving genetic predispositions, environmental factors like UV light exposure, and immunological mechanisms leading to skin damage.

In children, DLE typically presents as well-demarcated, erythematous plaques with scale and follicular plugging, primarily affecting the scalp. Lesions may also exhibit changes in pigmentation, atrophy, and telangiectasia. The scalp involvement often leads to scarring alopecia, which can be distressing for pediatric patients. Unlike systemic lupus erythematosus (SLE), DLE is usually limited to the skin without systemic involvement. The progression of DLE to systemic lupus erythematosus in children has been previously described to be 22.2%. In a recent report of 201 pediatric cases of DLE, 12% of the cases progressed to systemic lupus erythematosus (SLE) and 14.5% had concurrent SLE. The onset of symptoms before the age of 10 years was the only statistically significant predictor for progression to SLE. Pruritus is a common symptom and may be correlated with disease activity.

The differential diagnosis for this patient encompassed a variety of conditions, including tinea capitis, alopecia areata, trichotillomania, and lichen planopilaris, each considered based on clinical presentation but ultimately excluded through clinical, microscopic, and biopsy findings.

Matiz_Catalina_SanDiego.jpg

Conclusion

The prognosis for pediatric scalp DLE can be favorable with timely and appropriate management, underscoring the importance of early diagnosis and intervention to prevent scarring and hair loss. However, ongoing surveillance is crucial for monitoring potential progression to systemic lupus erythematosus, albeit a low-risk transformation.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

1. George PM and Tunnessen WW. Childhood discoid lupus erythematosus. Arch Dermatol. 1993;129(5):613-617.

2. Hawat T et al. Pediatric discoid lupus erythematosus: Short report. Dermatol Ther. 2022 Jan;35(1):e15170. doi: 10.1111/dth.15170.

3. Arkin LM et al. Practice-based differences in paediatric discoid lupus erythematosus. Br J Dermatol. 2019 Oct;181(4):805-810. doi: 10.1111/bjd.17780.

KOH analysis of the scales from the scalp areas revealed no fungal elements. Given the observed erythema and scaling, a punch biopsy was conducted. Histopathological examination of the biopsy sample displayed interface inflammation affecting both the infundibular and lower portions of hair follicles. The presence of folliculosebaceous units transitioning from intermediate to terminal size follicles was noted. A perifollicular, peri eccrine, superficial, and deep perivascular lymphoplasmacytic infiltrate was identified, alongside increased dermal mucin, findings consistent with a diagnosis of discoid lupus erythematosus.

Subsequent laboratory investigations were largely unremarkable, except for an elevated ANA titer (1:320, with a speckled pattern). The patient was initiated on a treatment regimen comprising intralesional triamcinolone and oral hydroxychloroquine (Plaquenil).

167686_scalp1_web.jpg

Discussion

Pediatric discoid lupus erythematosus (DLE) is a rare but chronic autoimmune condition, representing one of the most prevalent forms of cutaneous lupus erythematosus. It predominantly affects adults, yet pediatric cases account for 5%-7% of DLE diagnoses, with a significant predominance in females. Pediatric scalp DLE is particularly concerning due to its potential for causing scarring and permanent hair loss, which can significantly impact the psychological wellbeing of affected children.

The pathogenesis of DLE is multifactorial, involving genetic predispositions, environmental factors like UV light exposure, and immunological mechanisms leading to skin damage.

In children, DLE typically presents as well-demarcated, erythematous plaques with scale and follicular plugging, primarily affecting the scalp. Lesions may also exhibit changes in pigmentation, atrophy, and telangiectasia. The scalp involvement often leads to scarring alopecia, which can be distressing for pediatric patients. Unlike systemic lupus erythematosus (SLE), DLE is usually limited to the skin without systemic involvement. The progression of DLE to systemic lupus erythematosus in children has been previously described to be 22.2%. In a recent report of 201 pediatric cases of DLE, 12% of the cases progressed to systemic lupus erythematosus (SLE) and 14.5% had concurrent SLE. The onset of symptoms before the age of 10 years was the only statistically significant predictor for progression to SLE. Pruritus is a common symptom and may be correlated with disease activity.

The differential diagnosis for this patient encompassed a variety of conditions, including tinea capitis, alopecia areata, trichotillomania, and lichen planopilaris, each considered based on clinical presentation but ultimately excluded through clinical, microscopic, and biopsy findings.

Matiz_Catalina_SanDiego.jpg

Conclusion

The prognosis for pediatric scalp DLE can be favorable with timely and appropriate management, underscoring the importance of early diagnosis and intervention to prevent scarring and hair loss. However, ongoing surveillance is crucial for monitoring potential progression to systemic lupus erythematosus, albeit a low-risk transformation.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

1. George PM and Tunnessen WW. Childhood discoid lupus erythematosus. Arch Dermatol. 1993;129(5):613-617.

2. Hawat T et al. Pediatric discoid lupus erythematosus: Short report. Dermatol Ther. 2022 Jan;35(1):e15170. doi: 10.1111/dth.15170.

3. Arkin LM et al. Practice-based differences in paediatric discoid lupus erythematosus. Br J Dermatol. 2019 Oct;181(4):805-810. doi: 10.1111/bjd.17780.

KOH analysis of the scales from the scalp areas revealed no fungal elements. Given the observed erythema and scaling, a punch biopsy was conducted. Histopathological examination of the biopsy sample displayed interface inflammation affecting both the infundibular and lower portions of hair follicles. The presence of folliculosebaceous units transitioning from intermediate to terminal size follicles was noted. A perifollicular, peri eccrine, superficial, and deep perivascular lymphoplasmacytic infiltrate was identified, alongside increased dermal mucin, findings consistent with a diagnosis of discoid lupus erythematosus.

Subsequent laboratory investigations were largely unremarkable, except for an elevated ANA titer (1:320, with a speckled pattern). The patient was initiated on a treatment regimen comprising intralesional triamcinolone and oral hydroxychloroquine (Plaquenil).

167686_scalp1_web.jpg

Discussion

Pediatric discoid lupus erythematosus (DLE) is a rare but chronic autoimmune condition, representing one of the most prevalent forms of cutaneous lupus erythematosus. It predominantly affects adults, yet pediatric cases account for 5%-7% of DLE diagnoses, with a significant predominance in females. Pediatric scalp DLE is particularly concerning due to its potential for causing scarring and permanent hair loss, which can significantly impact the psychological wellbeing of affected children.

The pathogenesis of DLE is multifactorial, involving genetic predispositions, environmental factors like UV light exposure, and immunological mechanisms leading to skin damage.

In children, DLE typically presents as well-demarcated, erythematous plaques with scale and follicular plugging, primarily affecting the scalp. Lesions may also exhibit changes in pigmentation, atrophy, and telangiectasia. The scalp involvement often leads to scarring alopecia, which can be distressing for pediatric patients. Unlike systemic lupus erythematosus (SLE), DLE is usually limited to the skin without systemic involvement. The progression of DLE to systemic lupus erythematosus in children has been previously described to be 22.2%. In a recent report of 201 pediatric cases of DLE, 12% of the cases progressed to systemic lupus erythematosus (SLE) and 14.5% had concurrent SLE. The onset of symptoms before the age of 10 years was the only statistically significant predictor for progression to SLE. Pruritus is a common symptom and may be correlated with disease activity.

The differential diagnosis for this patient encompassed a variety of conditions, including tinea capitis, alopecia areata, trichotillomania, and lichen planopilaris, each considered based on clinical presentation but ultimately excluded through clinical, microscopic, and biopsy findings.

Matiz_Catalina_SanDiego.jpg

Conclusion

The prognosis for pediatric scalp DLE can be favorable with timely and appropriate management, underscoring the importance of early diagnosis and intervention to prevent scarring and hair loss. However, ongoing surveillance is crucial for monitoring potential progression to systemic lupus erythematosus, albeit a low-risk transformation.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

1. George PM and Tunnessen WW. Childhood discoid lupus erythematosus. Arch Dermatol. 1993;129(5):613-617.

2. Hawat T et al. Pediatric discoid lupus erythematosus: Short report. Dermatol Ther. 2022 Jan;35(1):e15170. doi: 10.1111/dth.15170.

3. Arkin LM et al. Practice-based differences in paediatric discoid lupus erythematosus. Br J Dermatol. 2019 Oct;181(4):805-810. doi: 10.1111/bjd.17780.

During examination, the patient was observed repetitively cracking his knuckles, making a fist with the right hand, placing the left hand on top, and rubbing the hand, a behavior he routinely did multiple times daily. The observed pattern of finger involvement on the dorsum of the right hand corresponded to areas subjected to significant pressure during the described activity. Consequently, a diagnosis of lichen simplex chronicus (LSC) secondary to mechanical rubbing, along with associated pachydermodactyly on the fingers of the right hand, was established.

166925_clenched_hands_web.jpg

Lichen simplex chronicus and pachydermodactyly are both attributed to microtrauma inflicted upon the skin. Lichen simplex chronicus often constitutes a diagnosis of exclusion and is characterized by repetitive trauma-induced keratinocyte proliferation and melanocyte activation, resulting in hyperpigmentation and skin thickening. Although typically observed in women between the fourth and fifth decades of life, LSC is rarely reported in children. In adults, LSC-related rubbing or scratching frequently arises from chronic pruritic dermatitis such as eczema or psoriasis, neurodermatitis from dysesthesia, or habitual movements, as exhibited by this young patient. While generally benign, LSC may become infected. In rare instances, malignant transformation may occur.

The association with pachydermodactyly implicates microtrauma, necessitating careful observation and questioning to elucidate the cause, as demonstrated in this case. Lesions are typically hyperpigmented, though cases of associated hypopigmentation or depigmentation have been documented. Affected areas typically fall within the patient’s hand and finger reach, with lesion improvement over several months achievable through trigger avoidance.
 

Pachydermodactyly, a rare but benign fibromatosis around the proximal interphalangeal joints, is often misdiagnosed as juvenile idiopathic arthritis, potentially leading to unnecessary treatments and patient anxiety. Microtrauma history due to digit manipulation is prevalent among affected individuals, with most also exhibiting neuropsychiatric disorders. Histological examination of pachydermodactyly reveals hypergranulosis and dermal thickening, accompanied by increased fibroblasts and collagen types I, III, and V, differing from the epidermal changes seen in LSC.

The differential diagnosis also included phytophotodermatitis, a phototoxic dermatologic reaction following exposure to ultraviolet light subsequent to contact with furocoumarin-containing plant chemicals. However, the persistence of the patient’s lesions for over a year precluded this diagnosis. Secondary hyperpigmentation was also contemplated but excluded due to the absence of preceding inflammatory dermatitis.

Matiz_Catalina_SanDiego.jpg

Treatment of LSC primarily involves identifying and addressing any underlying conditions, repairing the skin barrier, reducing inflammation, and modifying behaviors contributing to chronic microtrauma, as observed in this patient. Topical corticosteroids may aid in decreasing epidermal thickening and discoloration, though lesion resolution necessitates behavior cessation.

It’s important to identify these types of skin changes in children to avoid unnecessary medical treatments for these benign conditions.
 

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested Reading

Seier JA, Dissemond J. Lichen Simplex Chronicus Due to Mechanical Irritation. Dtsch Arztebl Int. 2022 Nov 18;119(46):802. doi: 10.3238/arztebl.m2022.0213.

Small S et al. A 12-Year-Old Boy Presenting With Unilateral Proximal Interphalangeal Joint Swelling. BMJ Case Rep. 2011 Apr 13:2011:bcr0120113719. doi: 10.1136/bcr.01.2011.3719.

Voicu C et al Lichen Simplex Chronicus as an Essential Part of the Dermatologic Masquerade. Open Access Maced J Med Sci. 2017 Jul 24;5(4):556-557. doi: 10.3889/oamjms.2017.133.

During examination, the patient was observed repetitively cracking his knuckles, making a fist with the right hand, placing the left hand on top, and rubbing the hand, a behavior he routinely did multiple times daily. The observed pattern of finger involvement on the dorsum of the right hand corresponded to areas subjected to significant pressure during the described activity. Consequently, a diagnosis of lichen simplex chronicus (LSC) secondary to mechanical rubbing, along with associated pachydermodactyly on the fingers of the right hand, was established.

166925_clenched_hands_web.jpg

Lichen simplex chronicus and pachydermodactyly are both attributed to microtrauma inflicted upon the skin. Lichen simplex chronicus often constitutes a diagnosis of exclusion and is characterized by repetitive trauma-induced keratinocyte proliferation and melanocyte activation, resulting in hyperpigmentation and skin thickening. Although typically observed in women between the fourth and fifth decades of life, LSC is rarely reported in children. In adults, LSC-related rubbing or scratching frequently arises from chronic pruritic dermatitis such as eczema or psoriasis, neurodermatitis from dysesthesia, or habitual movements, as exhibited by this young patient. While generally benign, LSC may become infected. In rare instances, malignant transformation may occur.

The association with pachydermodactyly implicates microtrauma, necessitating careful observation and questioning to elucidate the cause, as demonstrated in this case. Lesions are typically hyperpigmented, though cases of associated hypopigmentation or depigmentation have been documented. Affected areas typically fall within the patient’s hand and finger reach, with lesion improvement over several months achievable through trigger avoidance.
 

Pachydermodactyly, a rare but benign fibromatosis around the proximal interphalangeal joints, is often misdiagnosed as juvenile idiopathic arthritis, potentially leading to unnecessary treatments and patient anxiety. Microtrauma history due to digit manipulation is prevalent among affected individuals, with most also exhibiting neuropsychiatric disorders. Histological examination of pachydermodactyly reveals hypergranulosis and dermal thickening, accompanied by increased fibroblasts and collagen types I, III, and V, differing from the epidermal changes seen in LSC.

The differential diagnosis also included phytophotodermatitis, a phototoxic dermatologic reaction following exposure to ultraviolet light subsequent to contact with furocoumarin-containing plant chemicals. However, the persistence of the patient’s lesions for over a year precluded this diagnosis. Secondary hyperpigmentation was also contemplated but excluded due to the absence of preceding inflammatory dermatitis.

Matiz_Catalina_SanDiego.jpg

Treatment of LSC primarily involves identifying and addressing any underlying conditions, repairing the skin barrier, reducing inflammation, and modifying behaviors contributing to chronic microtrauma, as observed in this patient. Topical corticosteroids may aid in decreasing epidermal thickening and discoloration, though lesion resolution necessitates behavior cessation.

It’s important to identify these types of skin changes in children to avoid unnecessary medical treatments for these benign conditions.
 

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested Reading

Seier JA, Dissemond J. Lichen Simplex Chronicus Due to Mechanical Irritation. Dtsch Arztebl Int. 2022 Nov 18;119(46):802. doi: 10.3238/arztebl.m2022.0213.

Small S et al. A 12-Year-Old Boy Presenting With Unilateral Proximal Interphalangeal Joint Swelling. BMJ Case Rep. 2011 Apr 13:2011:bcr0120113719. doi: 10.1136/bcr.01.2011.3719.

Voicu C et al Lichen Simplex Chronicus as an Essential Part of the Dermatologic Masquerade. Open Access Maced J Med Sci. 2017 Jul 24;5(4):556-557. doi: 10.3889/oamjms.2017.133.

During examination, the patient was observed repetitively cracking his knuckles, making a fist with the right hand, placing the left hand on top, and rubbing the hand, a behavior he routinely did multiple times daily. The observed pattern of finger involvement on the dorsum of the right hand corresponded to areas subjected to significant pressure during the described activity. Consequently, a diagnosis of lichen simplex chronicus (LSC) secondary to mechanical rubbing, along with associated pachydermodactyly on the fingers of the right hand, was established.

166925_clenched_hands_web.jpg

Lichen simplex chronicus and pachydermodactyly are both attributed to microtrauma inflicted upon the skin. Lichen simplex chronicus often constitutes a diagnosis of exclusion and is characterized by repetitive trauma-induced keratinocyte proliferation and melanocyte activation, resulting in hyperpigmentation and skin thickening. Although typically observed in women between the fourth and fifth decades of life, LSC is rarely reported in children. In adults, LSC-related rubbing or scratching frequently arises from chronic pruritic dermatitis such as eczema or psoriasis, neurodermatitis from dysesthesia, or habitual movements, as exhibited by this young patient. While generally benign, LSC may become infected. In rare instances, malignant transformation may occur.

The association with pachydermodactyly implicates microtrauma, necessitating careful observation and questioning to elucidate the cause, as demonstrated in this case. Lesions are typically hyperpigmented, though cases of associated hypopigmentation or depigmentation have been documented. Affected areas typically fall within the patient’s hand and finger reach, with lesion improvement over several months achievable through trigger avoidance.
 

Pachydermodactyly, a rare but benign fibromatosis around the proximal interphalangeal joints, is often misdiagnosed as juvenile idiopathic arthritis, potentially leading to unnecessary treatments and patient anxiety. Microtrauma history due to digit manipulation is prevalent among affected individuals, with most also exhibiting neuropsychiatric disorders. Histological examination of pachydermodactyly reveals hypergranulosis and dermal thickening, accompanied by increased fibroblasts and collagen types I, III, and V, differing from the epidermal changes seen in LSC.

The differential diagnosis also included phytophotodermatitis, a phototoxic dermatologic reaction following exposure to ultraviolet light subsequent to contact with furocoumarin-containing plant chemicals. However, the persistence of the patient’s lesions for over a year precluded this diagnosis. Secondary hyperpigmentation was also contemplated but excluded due to the absence of preceding inflammatory dermatitis.

Matiz_Catalina_SanDiego.jpg

Treatment of LSC primarily involves identifying and addressing any underlying conditions, repairing the skin barrier, reducing inflammation, and modifying behaviors contributing to chronic microtrauma, as observed in this patient. Topical corticosteroids may aid in decreasing epidermal thickening and discoloration, though lesion resolution necessitates behavior cessation.

It’s important to identify these types of skin changes in children to avoid unnecessary medical treatments for these benign conditions.
 

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested Reading

Seier JA, Dissemond J. Lichen Simplex Chronicus Due to Mechanical Irritation. Dtsch Arztebl Int. 2022 Nov 18;119(46):802. doi: 10.3238/arztebl.m2022.0213.

Small S et al. A 12-Year-Old Boy Presenting With Unilateral Proximal Interphalangeal Joint Swelling. BMJ Case Rep. 2011 Apr 13:2011:bcr0120113719. doi: 10.1136/bcr.01.2011.3719.

Voicu C et al Lichen Simplex Chronicus as an Essential Part of the Dermatologic Masquerade. Open Access Maced J Med Sci. 2017 Jul 24;5(4):556-557. doi: 10.3889/oamjms.2017.133.

Following the initial presentation, the lesion was initially considered an acquired port wine stain and the child was referred for laser treatment. Upon reassessment during laser treatment a few months later, the lesion had progressed to hyper- and hypopigmented plaques with associated tissue sclerosis and bone atrophy on the mid forehead, nose, and scalp. Patches of alopecia and atrophy were observed on the frontal scalp. The diagnosis was revised to linear morphea en coup de sabre and the child was referred to pediatric rheumatology and commenced treatment with methotrexate and oral corticosteroids.

Matiz_Catalina_SanDiego.jpg

Linear morphea, a rare connective tissue disorder, primarily affects girls in the first 2 decades of life. Lesions can initially present in many ways. Usually, they present as hypo- or hyperpigmented patches, but may also present as lichenoid uncolored or pink plaques resembling lichen striatus. There may also be erythematous patches mimicking a capillary malformation, as seen in our patient. A recent article reviewing the progression of the lesions from erythematous patches to sclerosis suggests it occurs between 3 and 7 months of age. Subsequent stages manifest as significant atrophy, hypo- and hyperpigmentation, and in severe cases, bone atrophy and deformity, often causing substantial cosmetic disfigurement and functional impairment.

Pathophysiologically, linear morphea involves a complex interplay of immunologic, vascular, and fibrotic processes. While the initial triggers remain elusive, dysregulated immune responses leading to endothelial injury, subsequent activation of fibroblasts and myofibroblasts, and excessive collagen deposition are implicated. Angiogenic disturbances exacerbate tissue ischemia, perpetuating the fibrotic cascade. Alterations in cytokine signaling pathways, particularly TGF-beta and interleukin-6, play pivotal roles in promoting fibrosis and modulating the inflammatory milieu.

Diagnosis of linear morphea en coup de sabre relies on clinical examination, imaging (ultrasonography, MRI, CT scan), and skin biopsy for histopathological analysis. Imaging helps evaluate tissue involvement, while histology reveals characteristic dermal sclerosis, collagen deposition, and inflammation. Early-stage histology may show telangiectatic changes, complicating its differentiation from capillary malformation.

Treatment aims to mitigate symptoms, halt disease progression, and improve cosmesis and functionality. This involves a multidisciplinary approach with systemic medications, phototherapy, physical therapy, and surgical interventions in severe cases. Early identification is crucial for systemic treatments such as methotrexate and systemic corticosteroids to arrest disease progression. Other adjunctive therapies include topical corticosteroids, calcineurin inhibitors, and phototherapy. Surgical procedures like tissue expansion or autologous fat grafting may address tissue atrophy and deformities.

Linear morphea en coup de sabre presents diagnostic and therapeutic challenges because of its rarity and variable clinical course. Collaborative efforts among dermatologists, rheumatologists, radiologists, and surgeons are essential for accurate diagnosis, evaluation, and tailored management. Continued research into pathogenesis and novel therapeutic agents is pivotal to enhance understanding and improve outcomes for those affected by this enigmatic dermatologic condition.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Gomez-Garcia LA et al. Pediatr Dermatol. 2022 Mar;39(2):275-80.

Ng SS, Tay YK. J Cosmet Laser Ther. 2015;17(5):277-80.

Nijhawan RI et al. J Am Acad Dermatol. 2011 Apr;64(4):779-82.

Following the initial presentation, the lesion was initially considered an acquired port wine stain and the child was referred for laser treatment. Upon reassessment during laser treatment a few months later, the lesion had progressed to hyper- and hypopigmented plaques with associated tissue sclerosis and bone atrophy on the mid forehead, nose, and scalp. Patches of alopecia and atrophy were observed on the frontal scalp. The diagnosis was revised to linear morphea en coup de sabre and the child was referred to pediatric rheumatology and commenced treatment with methotrexate and oral corticosteroids.

Matiz_Catalina_SanDiego.jpg

Linear morphea, a rare connective tissue disorder, primarily affects girls in the first 2 decades of life. Lesions can initially present in many ways. Usually, they present as hypo- or hyperpigmented patches, but may also present as lichenoid uncolored or pink plaques resembling lichen striatus. There may also be erythematous patches mimicking a capillary malformation, as seen in our patient. A recent article reviewing the progression of the lesions from erythematous patches to sclerosis suggests it occurs between 3 and 7 months of age. Subsequent stages manifest as significant atrophy, hypo- and hyperpigmentation, and in severe cases, bone atrophy and deformity, often causing substantial cosmetic disfigurement and functional impairment.

Pathophysiologically, linear morphea involves a complex interplay of immunologic, vascular, and fibrotic processes. While the initial triggers remain elusive, dysregulated immune responses leading to endothelial injury, subsequent activation of fibroblasts and myofibroblasts, and excessive collagen deposition are implicated. Angiogenic disturbances exacerbate tissue ischemia, perpetuating the fibrotic cascade. Alterations in cytokine signaling pathways, particularly TGF-beta and interleukin-6, play pivotal roles in promoting fibrosis and modulating the inflammatory milieu.

Diagnosis of linear morphea en coup de sabre relies on clinical examination, imaging (ultrasonography, MRI, CT scan), and skin biopsy for histopathological analysis. Imaging helps evaluate tissue involvement, while histology reveals characteristic dermal sclerosis, collagen deposition, and inflammation. Early-stage histology may show telangiectatic changes, complicating its differentiation from capillary malformation.

Treatment aims to mitigate symptoms, halt disease progression, and improve cosmesis and functionality. This involves a multidisciplinary approach with systemic medications, phototherapy, physical therapy, and surgical interventions in severe cases. Early identification is crucial for systemic treatments such as methotrexate and systemic corticosteroids to arrest disease progression. Other adjunctive therapies include topical corticosteroids, calcineurin inhibitors, and phototherapy. Surgical procedures like tissue expansion or autologous fat grafting may address tissue atrophy and deformities.

Linear morphea en coup de sabre presents diagnostic and therapeutic challenges because of its rarity and variable clinical course. Collaborative efforts among dermatologists, rheumatologists, radiologists, and surgeons are essential for accurate diagnosis, evaluation, and tailored management. Continued research into pathogenesis and novel therapeutic agents is pivotal to enhance understanding and improve outcomes for those affected by this enigmatic dermatologic condition.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Gomez-Garcia LA et al. Pediatr Dermatol. 2022 Mar;39(2):275-80.

Ng SS, Tay YK. J Cosmet Laser Ther. 2015;17(5):277-80.

Nijhawan RI et al. J Am Acad Dermatol. 2011 Apr;64(4):779-82.

Following the initial presentation, the lesion was initially considered an acquired port wine stain and the child was referred for laser treatment. Upon reassessment during laser treatment a few months later, the lesion had progressed to hyper- and hypopigmented plaques with associated tissue sclerosis and bone atrophy on the mid forehead, nose, and scalp. Patches of alopecia and atrophy were observed on the frontal scalp. The diagnosis was revised to linear morphea en coup de sabre and the child was referred to pediatric rheumatology and commenced treatment with methotrexate and oral corticosteroids.

Matiz_Catalina_SanDiego.jpg

Linear morphea, a rare connective tissue disorder, primarily affects girls in the first 2 decades of life. Lesions can initially present in many ways. Usually, they present as hypo- or hyperpigmented patches, but may also present as lichenoid uncolored or pink plaques resembling lichen striatus. There may also be erythematous patches mimicking a capillary malformation, as seen in our patient. A recent article reviewing the progression of the lesions from erythematous patches to sclerosis suggests it occurs between 3 and 7 months of age. Subsequent stages manifest as significant atrophy, hypo- and hyperpigmentation, and in severe cases, bone atrophy and deformity, often causing substantial cosmetic disfigurement and functional impairment.

Pathophysiologically, linear morphea involves a complex interplay of immunologic, vascular, and fibrotic processes. While the initial triggers remain elusive, dysregulated immune responses leading to endothelial injury, subsequent activation of fibroblasts and myofibroblasts, and excessive collagen deposition are implicated. Angiogenic disturbances exacerbate tissue ischemia, perpetuating the fibrotic cascade. Alterations in cytokine signaling pathways, particularly TGF-beta and interleukin-6, play pivotal roles in promoting fibrosis and modulating the inflammatory milieu.

Diagnosis of linear morphea en coup de sabre relies on clinical examination, imaging (ultrasonography, MRI, CT scan), and skin biopsy for histopathological analysis. Imaging helps evaluate tissue involvement, while histology reveals characteristic dermal sclerosis, collagen deposition, and inflammation. Early-stage histology may show telangiectatic changes, complicating its differentiation from capillary malformation.

Treatment aims to mitigate symptoms, halt disease progression, and improve cosmesis and functionality. This involves a multidisciplinary approach with systemic medications, phototherapy, physical therapy, and surgical interventions in severe cases. Early identification is crucial for systemic treatments such as methotrexate and systemic corticosteroids to arrest disease progression. Other adjunctive therapies include topical corticosteroids, calcineurin inhibitors, and phototherapy. Surgical procedures like tissue expansion or autologous fat grafting may address tissue atrophy and deformities.

Linear morphea en coup de sabre presents diagnostic and therapeutic challenges because of its rarity and variable clinical course. Collaborative efforts among dermatologists, rheumatologists, radiologists, and surgeons are essential for accurate diagnosis, evaluation, and tailored management. Continued research into pathogenesis and novel therapeutic agents is pivotal to enhance understanding and improve outcomes for those affected by this enigmatic dermatologic condition.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Gomez-Garcia LA et al. Pediatr Dermatol. 2022 Mar;39(2):275-80.

Ng SS, Tay YK. J Cosmet Laser Ther. 2015;17(5):277-80.

Nijhawan RI et al. J Am Acad Dermatol. 2011 Apr;64(4):779-82.

The lesions on the heels are consistent with piezogenic pedal papules. Piezogenic pedal papules are a relatively common and underreported skin condition that can affect people of all ages, including adolescents. They seem to be more common in women and have been described in families, though a genetic link hasn’t been elucidated. PPP manifests as small, soft, compressible papules on the lateral aspects of the skin on the heels, more noticeable when the patient is standing, and can also present on the wrists and legs. While they may not be a cause for serious concern, understanding their causes, associated conditions, and management is important.

Piezogenic pedal papules are flesh-colored or slightly reddish and can range in size from a few millimeters to a centimeter or more. They are described as benign herniations of elastic tissue and subcutaneous fat through the reticular dermis. The lesions are triggered by increased pressure and compression, such as standing or the application of pressure on the heel. The exact etiology is not known. While piezogenic pedal papules are often asymptomatic, some individuals experience discomfort, itching, or mild pain, particularly when walking or applying pressure to the affected area, especially in patients with Ehlers-Danlos syndrome (EDS).

Individuals who may be at risk of developing these lesions include obese patients, individuals with pes planus, and people who have occupations that require long periods of standing. It can also be seen in athletes who participate in long-distance running or high-impact sports. Piezogenic pedal papules have been described as one of the core skin findings in patients with hypermobile Ehlers-Danlos syndrome (hEDS), which also includes skin hyperextensibility, joint hypermobility, tissue fragility with atrophic cutaneous scars, and abnormal bruising and bleeding. Our patient presented with some of these characteristics (piezogenic papules, soft elastic skin, and some joint hypermobility) but did not fulfill all the criteria for the diagnosis of hEDS or other types of EDS.

The diagnosis of hEDS is based on the 2017 diagnostic criteria checklist. To be diagnosed with hEDS, the patient may have all three parts of the diagnostic criteria. The three domains include generalized joint hypermobility (partially met by our patient), evidence of syndromic features, musculoskeletal complications, and/or family history (she had a few of these criteria, including piezogenic papules and striae), and the exclusion of alternative diagnoses (see references for the PDF checklist). As she does have some features, we diagnosed her with hypermobility spectrum disorder. There is no genetic testing available for the hypermobile spectrum disorder or the hypermobile type of EDS. Given that these patients can present with mitral valve prolapse, she was referred to a cardiac echocardiogram, which was reported as normal.

The diagnosis of PPP is made clinically, and rarely a biopsy is required. Biopsies of the lesions show hyperkeratosis, degeneration of the thin fibrous septa between fat lobules, and subsequent coalescence of fat. If the presentation is atypical, a high-frequency ultrasound can be requested to confirm the physical exam findings.

If the lesions are fixed, firm, and solitary, a diagnosis to consider is juvenile aponeurotic fibroma, which occurs more often in children and adolescents on the wrists and is less common on the ankles. If there is suspicion for this condition, a plain radiograph will show stippled calcifications.

PPP are usually asymptomatic and need no further treatment. When they are symptomatic, conservative management should be considered first, which includes behavioral modifications, weight loss, avoidance of prolonged standing, and reduced foot trauma. If these are not successful, compression socks, heel cups, and other orthotics can be recommended. Intralesional injections of betamethasone and bupivacaine have been reported as an option in patients with symptomatic PPP and a history of EDS.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested reading

Edimo CO et al. Int J Womens Dermatol. 2021 Jan. doi: 10.1016/j.ijwd.2021.01.020. Erratum in: Int J Womens Dermatol. 2021 Jul 31;7(5Part B):869-70.

Brown F, Cook C. Piezogenic Pedal Papule. 2023 Aug 16. In: StatPearls [Internet]. Treasure Island, Fla.: StatPearls Publishing, 2023. PMID: 29489228.

Levy HP. Hypermobile Ehlers-Danlos Syndrome. 2004 Oct 22 [Updated 2018 Jun 21]. In: Adam MP, Mirzaa GM, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle: University of Washington, Seattle; 1993-2023. Available from: www.ncbi.nlm.nih.gov/books/NBK1279/.

The International Consortium on Ehlers-Danlos Syndrome & Related Disorders. Diagnostic Criteria for Hypermobile Ehlers-Danlos Syndrome (hEDS). www.ehlers-danlos.com/wp-content/uploads/2017/05/hEDS-Dx-Criteria-checklist-1.pdf.

The lesions on the heels are consistent with piezogenic pedal papules. Piezogenic pedal papules are a relatively common and underreported skin condition that can affect people of all ages, including adolescents. They seem to be more common in women and have been described in families, though a genetic link hasn’t been elucidated. PPP manifests as small, soft, compressible papules on the lateral aspects of the skin on the heels, more noticeable when the patient is standing, and can also present on the wrists and legs. While they may not be a cause for serious concern, understanding their causes, associated conditions, and management is important.

Piezogenic pedal papules are flesh-colored or slightly reddish and can range in size from a few millimeters to a centimeter or more. They are described as benign herniations of elastic tissue and subcutaneous fat through the reticular dermis. The lesions are triggered by increased pressure and compression, such as standing or the application of pressure on the heel. The exact etiology is not known. While piezogenic pedal papules are often asymptomatic, some individuals experience discomfort, itching, or mild pain, particularly when walking or applying pressure to the affected area, especially in patients with Ehlers-Danlos syndrome (EDS).

Individuals who may be at risk of developing these lesions include obese patients, individuals with pes planus, and people who have occupations that require long periods of standing. It can also be seen in athletes who participate in long-distance running or high-impact sports. Piezogenic pedal papules have been described as one of the core skin findings in patients with hypermobile Ehlers-Danlos syndrome (hEDS), which also includes skin hyperextensibility, joint hypermobility, tissue fragility with atrophic cutaneous scars, and abnormal bruising and bleeding. Our patient presented with some of these characteristics (piezogenic papules, soft elastic skin, and some joint hypermobility) but did not fulfill all the criteria for the diagnosis of hEDS or other types of EDS.

The diagnosis of hEDS is based on the 2017 diagnostic criteria checklist. To be diagnosed with hEDS, the patient may have all three parts of the diagnostic criteria. The three domains include generalized joint hypermobility (partially met by our patient), evidence of syndromic features, musculoskeletal complications, and/or family history (she had a few of these criteria, including piezogenic papules and striae), and the exclusion of alternative diagnoses (see references for the PDF checklist). As she does have some features, we diagnosed her with hypermobility spectrum disorder. There is no genetic testing available for the hypermobile spectrum disorder or the hypermobile type of EDS. Given that these patients can present with mitral valve prolapse, she was referred to a cardiac echocardiogram, which was reported as normal.

The diagnosis of PPP is made clinically, and rarely a biopsy is required. Biopsies of the lesions show hyperkeratosis, degeneration of the thin fibrous septa between fat lobules, and subsequent coalescence of fat. If the presentation is atypical, a high-frequency ultrasound can be requested to confirm the physical exam findings.

If the lesions are fixed, firm, and solitary, a diagnosis to consider is juvenile aponeurotic fibroma, which occurs more often in children and adolescents on the wrists and is less common on the ankles. If there is suspicion for this condition, a plain radiograph will show stippled calcifications.

PPP are usually asymptomatic and need no further treatment. When they are symptomatic, conservative management should be considered first, which includes behavioral modifications, weight loss, avoidance of prolonged standing, and reduced foot trauma. If these are not successful, compression socks, heel cups, and other orthotics can be recommended. Intralesional injections of betamethasone and bupivacaine have been reported as an option in patients with symptomatic PPP and a history of EDS.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested reading

Edimo CO et al. Int J Womens Dermatol. 2021 Jan. doi: 10.1016/j.ijwd.2021.01.020. Erratum in: Int J Womens Dermatol. 2021 Jul 31;7(5Part B):869-70.

Brown F, Cook C. Piezogenic Pedal Papule. 2023 Aug 16. In: StatPearls [Internet]. Treasure Island, Fla.: StatPearls Publishing, 2023. PMID: 29489228.

Levy HP. Hypermobile Ehlers-Danlos Syndrome. 2004 Oct 22 [Updated 2018 Jun 21]. In: Adam MP, Mirzaa GM, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle: University of Washington, Seattle; 1993-2023. Available from: www.ncbi.nlm.nih.gov/books/NBK1279/.

The International Consortium on Ehlers-Danlos Syndrome & Related Disorders. Diagnostic Criteria for Hypermobile Ehlers-Danlos Syndrome (hEDS). www.ehlers-danlos.com/wp-content/uploads/2017/05/hEDS-Dx-Criteria-checklist-1.pdf.

The lesions on the heels are consistent with piezogenic pedal papules. Piezogenic pedal papules are a relatively common and underreported skin condition that can affect people of all ages, including adolescents. They seem to be more common in women and have been described in families, though a genetic link hasn’t been elucidated. PPP manifests as small, soft, compressible papules on the lateral aspects of the skin on the heels, more noticeable when the patient is standing, and can also present on the wrists and legs. While they may not be a cause for serious concern, understanding their causes, associated conditions, and management is important.

Piezogenic pedal papules are flesh-colored or slightly reddish and can range in size from a few millimeters to a centimeter or more. They are described as benign herniations of elastic tissue and subcutaneous fat through the reticular dermis. The lesions are triggered by increased pressure and compression, such as standing or the application of pressure on the heel. The exact etiology is not known. While piezogenic pedal papules are often asymptomatic, some individuals experience discomfort, itching, or mild pain, particularly when walking or applying pressure to the affected area, especially in patients with Ehlers-Danlos syndrome (EDS).

Individuals who may be at risk of developing these lesions include obese patients, individuals with pes planus, and people who have occupations that require long periods of standing. It can also be seen in athletes who participate in long-distance running or high-impact sports. Piezogenic pedal papules have been described as one of the core skin findings in patients with hypermobile Ehlers-Danlos syndrome (hEDS), which also includes skin hyperextensibility, joint hypermobility, tissue fragility with atrophic cutaneous scars, and abnormal bruising and bleeding. Our patient presented with some of these characteristics (piezogenic papules, soft elastic skin, and some joint hypermobility) but did not fulfill all the criteria for the diagnosis of hEDS or other types of EDS.

The diagnosis of hEDS is based on the 2017 diagnostic criteria checklist. To be diagnosed with hEDS, the patient may have all three parts of the diagnostic criteria. The three domains include generalized joint hypermobility (partially met by our patient), evidence of syndromic features, musculoskeletal complications, and/or family history (she had a few of these criteria, including piezogenic papules and striae), and the exclusion of alternative diagnoses (see references for the PDF checklist). As she does have some features, we diagnosed her with hypermobility spectrum disorder. There is no genetic testing available for the hypermobile spectrum disorder or the hypermobile type of EDS. Given that these patients can present with mitral valve prolapse, she was referred to a cardiac echocardiogram, which was reported as normal.

The diagnosis of PPP is made clinically, and rarely a biopsy is required. Biopsies of the lesions show hyperkeratosis, degeneration of the thin fibrous septa between fat lobules, and subsequent coalescence of fat. If the presentation is atypical, a high-frequency ultrasound can be requested to confirm the physical exam findings.

If the lesions are fixed, firm, and solitary, a diagnosis to consider is juvenile aponeurotic fibroma, which occurs more often in children and adolescents on the wrists and is less common on the ankles. If there is suspicion for this condition, a plain radiograph will show stippled calcifications.

PPP are usually asymptomatic and need no further treatment. When they are symptomatic, conservative management should be considered first, which includes behavioral modifications, weight loss, avoidance of prolonged standing, and reduced foot trauma. If these are not successful, compression socks, heel cups, and other orthotics can be recommended. Intralesional injections of betamethasone and bupivacaine have been reported as an option in patients with symptomatic PPP and a history of EDS.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

Suggested reading

Edimo CO et al. Int J Womens Dermatol. 2021 Jan. doi: 10.1016/j.ijwd.2021.01.020. Erratum in: Int J Womens Dermatol. 2021 Jul 31;7(5Part B):869-70.

Brown F, Cook C. Piezogenic Pedal Papule. 2023 Aug 16. In: StatPearls [Internet]. Treasure Island, Fla.: StatPearls Publishing, 2023. PMID: 29489228.

Levy HP. Hypermobile Ehlers-Danlos Syndrome. 2004 Oct 22 [Updated 2018 Jun 21]. In: Adam MP, Mirzaa GM, Pagon RA, et al., editors. GeneReviews® [Internet]. Seattle: University of Washington, Seattle; 1993-2023. Available from: www.ncbi.nlm.nih.gov/books/NBK1279/.

The International Consortium on Ehlers-Danlos Syndrome & Related Disorders. Diagnostic Criteria for Hypermobile Ehlers-Danlos Syndrome (hEDS). www.ehlers-danlos.com/wp-content/uploads/2017/05/hEDS-Dx-Criteria-checklist-1.pdf.

At the week follow-up, the lesions were unchanged and the swelling on the left lateral eyebrow was worsening. A biopsy of the yellow lesion on the back and one of the scaly papules on the abdomen was performed. A fungal and bacterial cultures were also ordered.

He was referred to ophthalmology for evaluation of the eyelid swelling and an ultrasound was requested.

The skin biopsy showed a clonal proliferation of reniform histiocytes with eosinophils within the dermis. The cells were positive for S100, CD207 (langerin), and CD1a and negative for pancytokeratin and Melan-A, supportive of the diagnosis of Langerhans cell histiocytosis (LCH).
 

Diagnosis

The patient was admitted to the hospital, where a skeletal survey was performed, which showed an asymmetric lucency involving the left frontal calvarium extending to the superior lateral orbital rim. The brain MRI demonstrated a destructive avidly enhancing soft-tissue process which involved the superior left orbital rim likely with some degree of intracranial extension. This lesion exerts mass effect upon surrounding structures to the left ocular globe. With the skin and skeletal findings, the patient was diagnosed with LCH. His blood count was significant for thrombocytopenia. His liver and kidney function were normal. His electrolytes were also with in normal range. He was started on chemotherapy with vinblastine and systemic corticosteroids with resolution of the rash and decrease on the size of the lesion on the orbit within a few weeks.

Infantile LCH is a rare neoplastic disorder of hematopoietic myeloid precursor cells caused by activating mutations in the mitogen-activated protein kinase (MAPK) pathway, particularly BRAF-V600E mutation. White male children are mostly affected, with a peak incidence of 1-3 years of age. Nine out of 10 children with cutaneous involvement also have multisystemic disease, such as the case of our patient. LCH is classified as single or multisystem organ disease. Two-thirds of the cases present with single system involvement. Organs most commonly affected include the bone (the skull being the most commonly affected), skin, and high-risk organs like the liver, spleen, and bone marrow, and less commonly the lungs, lymph nodes, and central nervous system. Some patients can present with fever, lethargy, and weight loss. None were noted in our patient.

Skin findings of LCH can have multiple morphologies and presentations and often described as a big mimicker. In young infants like our patient, the seborrheic dermatitis–mimicking type is often seen. In other cases, the skin lesions can appear eczematous, petechial, with scabbing, crusting, or purpura. Xanthoma-like lesions, like that one our patient had in the back, have also been described. Resistant diaper dermatitis and cradle cap should prompt the clinician to think about LCH. Lesions can be so varied that can present with hypopigmentation (vitiligo like), hyperpigmentation, varicella-like papulo-pustules, and red blue nodules within others. Oral mucosa and nail involvement can also occur.

Bone involvement can present as soft-tissue mass with swelling and pain as it occur in our patient.

Endocrinopathies have been described in patients with LCH including diabetes insipidus, growth hormone deficiency, and less likely thyroid disease.
 

Multidisciplinary care

The diagnosis of LCH in infants necessitates a combination of clinical, radiological, and histopathologic findings. In infants, cutaneous involvement is a frequent initial presentation, with characteristic lesions that are often misdiagnosed as other dermatologic conditions. Timely recognition of these lesions and appropriate skin biopsies for histological examination are essential steps in achieving an accurate diagnosis.

Radiological imaging, including x-rays, CT, and MRI, plays a crucial role in assessing the extent of involvement.

The management of LCH in infants requires a well-coordinated multidisciplinary approach involving pediatric oncologists, dermatologists, radiologists, orthopedic surgeons, and other relevant specialists. Treatment strategies vary depending on the extent of disease involvement and the presence of risk factors. In localized cases, observation with close monitoring may be considered, as some cases of LCH in infants may undergo spontaneous regression. However, cases with severe symptoms, extensive organ involvement, or high-risk features may require systemic therapies.

Matiz_Catalina_SanDiego.jpg

Chemotherapy agents, including vinblastine and prednisone have been utilized in the treatment of infantile LCH with varying success. The selection of treatment regimens should be tailored to each individual case, considering disease severity, potential toxicities, and long-term effects. In cases of bone lesions causing significant deformities or functional impairment, surgical intervention may be necessary. Skin only disease can be treated with topical corticosteroids.
 

Prognosis

Survival rates in patients with single-organ involvement without risk-organ involvement is close to 100% and with risk-organ involvement of 98% at 5 years.

Long-term follow-up is essential for infants diagnosed with LCH, as recurrence and late effects can occur even after successful treatment. Continued monitoring allows for the timely detection of relapses or the development of secondary complications.

Infants thought to have common skin conditions like eczema, seborrheic dermatitis, or diaper dermatitis not responding to treatment should be referred to pediatric dermatology for evaluation to rule out the possibility of LCH.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1035-44.

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1047-56.

Leung AKC et al. World J Pediatr. 2019 Dec;15(6):536-45.

At the week follow-up, the lesions were unchanged and the swelling on the left lateral eyebrow was worsening. A biopsy of the yellow lesion on the back and one of the scaly papules on the abdomen was performed. A fungal and bacterial cultures were also ordered.

He was referred to ophthalmology for evaluation of the eyelid swelling and an ultrasound was requested.

The skin biopsy showed a clonal proliferation of reniform histiocytes with eosinophils within the dermis. The cells were positive for S100, CD207 (langerin), and CD1a and negative for pancytokeratin and Melan-A, supportive of the diagnosis of Langerhans cell histiocytosis (LCH).
 

Diagnosis

The patient was admitted to the hospital, where a skeletal survey was performed, which showed an asymmetric lucency involving the left frontal calvarium extending to the superior lateral orbital rim. The brain MRI demonstrated a destructive avidly enhancing soft-tissue process which involved the superior left orbital rim likely with some degree of intracranial extension. This lesion exerts mass effect upon surrounding structures to the left ocular globe. With the skin and skeletal findings, the patient was diagnosed with LCH. His blood count was significant for thrombocytopenia. His liver and kidney function were normal. His electrolytes were also with in normal range. He was started on chemotherapy with vinblastine and systemic corticosteroids with resolution of the rash and decrease on the size of the lesion on the orbit within a few weeks.

Infantile LCH is a rare neoplastic disorder of hematopoietic myeloid precursor cells caused by activating mutations in the mitogen-activated protein kinase (MAPK) pathway, particularly BRAF-V600E mutation. White male children are mostly affected, with a peak incidence of 1-3 years of age. Nine out of 10 children with cutaneous involvement also have multisystemic disease, such as the case of our patient. LCH is classified as single or multisystem organ disease. Two-thirds of the cases present with single system involvement. Organs most commonly affected include the bone (the skull being the most commonly affected), skin, and high-risk organs like the liver, spleen, and bone marrow, and less commonly the lungs, lymph nodes, and central nervous system. Some patients can present with fever, lethargy, and weight loss. None were noted in our patient.

Skin findings of LCH can have multiple morphologies and presentations and often described as a big mimicker. In young infants like our patient, the seborrheic dermatitis–mimicking type is often seen. In other cases, the skin lesions can appear eczematous, petechial, with scabbing, crusting, or purpura. Xanthoma-like lesions, like that one our patient had in the back, have also been described. Resistant diaper dermatitis and cradle cap should prompt the clinician to think about LCH. Lesions can be so varied that can present with hypopigmentation (vitiligo like), hyperpigmentation, varicella-like papulo-pustules, and red blue nodules within others. Oral mucosa and nail involvement can also occur.

Bone involvement can present as soft-tissue mass with swelling and pain as it occur in our patient.

Endocrinopathies have been described in patients with LCH including diabetes insipidus, growth hormone deficiency, and less likely thyroid disease.
 

Multidisciplinary care

The diagnosis of LCH in infants necessitates a combination of clinical, radiological, and histopathologic findings. In infants, cutaneous involvement is a frequent initial presentation, with characteristic lesions that are often misdiagnosed as other dermatologic conditions. Timely recognition of these lesions and appropriate skin biopsies for histological examination are essential steps in achieving an accurate diagnosis.

Radiological imaging, including x-rays, CT, and MRI, plays a crucial role in assessing the extent of involvement.

The management of LCH in infants requires a well-coordinated multidisciplinary approach involving pediatric oncologists, dermatologists, radiologists, orthopedic surgeons, and other relevant specialists. Treatment strategies vary depending on the extent of disease involvement and the presence of risk factors. In localized cases, observation with close monitoring may be considered, as some cases of LCH in infants may undergo spontaneous regression. However, cases with severe symptoms, extensive organ involvement, or high-risk features may require systemic therapies.

Matiz_Catalina_SanDiego.jpg

Chemotherapy agents, including vinblastine and prednisone have been utilized in the treatment of infantile LCH with varying success. The selection of treatment regimens should be tailored to each individual case, considering disease severity, potential toxicities, and long-term effects. In cases of bone lesions causing significant deformities or functional impairment, surgical intervention may be necessary. Skin only disease can be treated with topical corticosteroids.
 

Prognosis

Survival rates in patients with single-organ involvement without risk-organ involvement is close to 100% and with risk-organ involvement of 98% at 5 years.

Long-term follow-up is essential for infants diagnosed with LCH, as recurrence and late effects can occur even after successful treatment. Continued monitoring allows for the timely detection of relapses or the development of secondary complications.

Infants thought to have common skin conditions like eczema, seborrheic dermatitis, or diaper dermatitis not responding to treatment should be referred to pediatric dermatology for evaluation to rule out the possibility of LCH.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1035-44.

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1047-56.

Leung AKC et al. World J Pediatr. 2019 Dec;15(6):536-45.

At the week follow-up, the lesions were unchanged and the swelling on the left lateral eyebrow was worsening. A biopsy of the yellow lesion on the back and one of the scaly papules on the abdomen was performed. A fungal and bacterial cultures were also ordered.

He was referred to ophthalmology for evaluation of the eyelid swelling and an ultrasound was requested.

The skin biopsy showed a clonal proliferation of reniform histiocytes with eosinophils within the dermis. The cells were positive for S100, CD207 (langerin), and CD1a and negative for pancytokeratin and Melan-A, supportive of the diagnosis of Langerhans cell histiocytosis (LCH).
 

Diagnosis

The patient was admitted to the hospital, where a skeletal survey was performed, which showed an asymmetric lucency involving the left frontal calvarium extending to the superior lateral orbital rim. The brain MRI demonstrated a destructive avidly enhancing soft-tissue process which involved the superior left orbital rim likely with some degree of intracranial extension. This lesion exerts mass effect upon surrounding structures to the left ocular globe. With the skin and skeletal findings, the patient was diagnosed with LCH. His blood count was significant for thrombocytopenia. His liver and kidney function were normal. His electrolytes were also with in normal range. He was started on chemotherapy with vinblastine and systemic corticosteroids with resolution of the rash and decrease on the size of the lesion on the orbit within a few weeks.

Infantile LCH is a rare neoplastic disorder of hematopoietic myeloid precursor cells caused by activating mutations in the mitogen-activated protein kinase (MAPK) pathway, particularly BRAF-V600E mutation. White male children are mostly affected, with a peak incidence of 1-3 years of age. Nine out of 10 children with cutaneous involvement also have multisystemic disease, such as the case of our patient. LCH is classified as single or multisystem organ disease. Two-thirds of the cases present with single system involvement. Organs most commonly affected include the bone (the skull being the most commonly affected), skin, and high-risk organs like the liver, spleen, and bone marrow, and less commonly the lungs, lymph nodes, and central nervous system. Some patients can present with fever, lethargy, and weight loss. None were noted in our patient.

Skin findings of LCH can have multiple morphologies and presentations and often described as a big mimicker. In young infants like our patient, the seborrheic dermatitis–mimicking type is often seen. In other cases, the skin lesions can appear eczematous, petechial, with scabbing, crusting, or purpura. Xanthoma-like lesions, like that one our patient had in the back, have also been described. Resistant diaper dermatitis and cradle cap should prompt the clinician to think about LCH. Lesions can be so varied that can present with hypopigmentation (vitiligo like), hyperpigmentation, varicella-like papulo-pustules, and red blue nodules within others. Oral mucosa and nail involvement can also occur.

Bone involvement can present as soft-tissue mass with swelling and pain as it occur in our patient.

Endocrinopathies have been described in patients with LCH including diabetes insipidus, growth hormone deficiency, and less likely thyroid disease.
 

Multidisciplinary care

The diagnosis of LCH in infants necessitates a combination of clinical, radiological, and histopathologic findings. In infants, cutaneous involvement is a frequent initial presentation, with characteristic lesions that are often misdiagnosed as other dermatologic conditions. Timely recognition of these lesions and appropriate skin biopsies for histological examination are essential steps in achieving an accurate diagnosis.

Radiological imaging, including x-rays, CT, and MRI, plays a crucial role in assessing the extent of involvement.

The management of LCH in infants requires a well-coordinated multidisciplinary approach involving pediatric oncologists, dermatologists, radiologists, orthopedic surgeons, and other relevant specialists. Treatment strategies vary depending on the extent of disease involvement and the presence of risk factors. In localized cases, observation with close monitoring may be considered, as some cases of LCH in infants may undergo spontaneous regression. However, cases with severe symptoms, extensive organ involvement, or high-risk features may require systemic therapies.

Matiz_Catalina_SanDiego.jpg

Chemotherapy agents, including vinblastine and prednisone have been utilized in the treatment of infantile LCH with varying success. The selection of treatment regimens should be tailored to each individual case, considering disease severity, potential toxicities, and long-term effects. In cases of bone lesions causing significant deformities or functional impairment, surgical intervention may be necessary. Skin only disease can be treated with topical corticosteroids.
 

Prognosis

Survival rates in patients with single-organ involvement without risk-organ involvement is close to 100% and with risk-organ involvement of 98% at 5 years.

Long-term follow-up is essential for infants diagnosed with LCH, as recurrence and late effects can occur even after successful treatment. Continued monitoring allows for the timely detection of relapses or the development of secondary complications.

Infants thought to have common skin conditions like eczema, seborrheic dermatitis, or diaper dermatitis not responding to treatment should be referred to pediatric dermatology for evaluation to rule out the possibility of LCH.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1035-44.

Krooks J et al. J Am Acad Dermatol. 2018 Jun;78(6):1047-56.

Leung AKC et al. World J Pediatr. 2019 Dec;15(6):536-45.

Given the presentation and the unique location of the lesions he was diagnosed with follicular keratosis of the chin (FKC).

This is a rare and poorly understood condition that can be present in older children and young teenagers. In the cases reported by Kanzaki et al.¹ were two boys who presented with the condition; it was thought to be associated with rubbing of the chin with their hands when watching TV or reading. The author described improvement with habit change. This condition is usually described in boys, and some cases presented in brothers,² suggesting a genetic predisposition. Some reports lack a history of rubbing or trauma to the area.

Histopathologic evaluation of the lesions demonstrates dilated hair follicles containing keratotic basophilic material without any signs of inflammation.

Matiz_Catalina_SanDiego.jpg

The lesions can be confused with keratosis pilaris (KP). Keratosis pilaris can be described in association with atopic dermatitis and ichthyosis, which were not present in our patient. The lesions usually present on the sides of the cheeks and lateral region of the arms and legs. Compared with follicular keratosis, KP lesions usually present with associated perifollicular erythema. Our patient did not present with lesions on the cheeks or the sides of the arms or legs. Milia can present on the chin of children, usually if there is history of rubbing or trauma, or on a scar. Milia are micro keratin cysts, usually seen in areas of the face. Lichen spinulous is described as rough small follicular papules that present in oval or circular patches that can grow up to 5 cm and spread rapidly. They usually present on the extensor surfaces of the extremities, neck, abdomen, and knees. These lesions are thought to be secondary to infections, have been associated with atopy, and have been seen in patients with atopic dermatitis. There is a probable genetic predisposition. The lesions are usually treated with gentle soaps and moisturizer containing keratolytics like urea or salicylic acid, and in some cases topical retinoids can also be tried. Follicular mucinosis can also present similarly to keratosis follicularis. The lesions present as scaly plaques or as grouped skin color papules on the face, scalp, or the neck that can also be associated with hair loss. Sometimes a biopsy needs to be done to be able to distinguish it from follicular keratosis. There is an increase of mucin around hair follicles and sebaceous glands with associated inflammation and degeneration of the follicular structures. In patients with primary follicular mucinosis the lesions can resolve spontaneously in a couple of years. Lesions can be treated with topical corticosteroids, oral antibiotics like macrolides or tetracyclines, dapsone, and phototherapy.

KFC can be treated with vitamin D analogues. It is usually unresponsive to corticosteroids, keratolytic lotions, and retinoids. Our patient was prescribed calcipotriene.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego

References

1. Kanzaki T et al. J Am Acad Dermatol. 1992;26(1):134-5.

2. Buechner AA et al. JAMA Dermatol. 2018 Jan 1;154(1):111-2.

Given the presentation and the unique location of the lesions he was diagnosed with follicular keratosis of the chin (FKC).

This is a rare and poorly understood condition that can be present in older children and young teenagers. In the cases reported by Kanzaki et al.¹ were two boys who presented with the condition; it was thought to be associated with rubbing of the chin with their hands when watching TV or reading. The author described improvement with habit change. This condition is usually described in boys, and some cases presented in brothers,² suggesting a genetic predisposition. Some reports lack a history of rubbing or trauma to the area.

Histopathologic evaluation of the lesions demonstrates dilated hair follicles containing keratotic basophilic material without any signs of inflammation.

Matiz_Catalina_SanDiego.jpg

The lesions can be confused with keratosis pilaris (KP). Keratosis pilaris can be described in association with atopic dermatitis and ichthyosis, which were not present in our patient. The lesions usually present on the sides of the cheeks and lateral region of the arms and legs. Compared with follicular keratosis, KP lesions usually present with associated perifollicular erythema. Our patient did not present with lesions on the cheeks or the sides of the arms or legs. Milia can present on the chin of children, usually if there is history of rubbing or trauma, or on a scar. Milia are micro keratin cysts, usually seen in areas of the face. Lichen spinulous is described as rough small follicular papules that present in oval or circular patches that can grow up to 5 cm and spread rapidly. They usually present on the extensor surfaces of the extremities, neck, abdomen, and knees. These lesions are thought to be secondary to infections, have been associated with atopy, and have been seen in patients with atopic dermatitis. There is a probable genetic predisposition. The lesions are usually treated with gentle soaps and moisturizer containing keratolytics like urea or salicylic acid, and in some cases topical retinoids can also be tried. Follicular mucinosis can also present similarly to keratosis follicularis. The lesions present as scaly plaques or as grouped skin color papules on the face, scalp, or the neck that can also be associated with hair loss. Sometimes a biopsy needs to be done to be able to distinguish it from follicular keratosis. There is an increase of mucin around hair follicles and sebaceous glands with associated inflammation and degeneration of the follicular structures. In patients with primary follicular mucinosis the lesions can resolve spontaneously in a couple of years. Lesions can be treated with topical corticosteroids, oral antibiotics like macrolides or tetracyclines, dapsone, and phototherapy.

KFC can be treated with vitamin D analogues. It is usually unresponsive to corticosteroids, keratolytic lotions, and retinoids. Our patient was prescribed calcipotriene.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego

References

1. Kanzaki T et al. J Am Acad Dermatol. 1992;26(1):134-5.

2. Buechner AA et al. JAMA Dermatol. 2018 Jan 1;154(1):111-2.

Given the presentation and the unique location of the lesions he was diagnosed with follicular keratosis of the chin (FKC).

This is a rare and poorly understood condition that can be present in older children and young teenagers. In the cases reported by Kanzaki et al.¹ were two boys who presented with the condition; it was thought to be associated with rubbing of the chin with their hands when watching TV or reading. The author described improvement with habit change. This condition is usually described in boys, and some cases presented in brothers,² suggesting a genetic predisposition. Some reports lack a history of rubbing or trauma to the area.

Histopathologic evaluation of the lesions demonstrates dilated hair follicles containing keratotic basophilic material without any signs of inflammation.

Matiz_Catalina_SanDiego.jpg

The lesions can be confused with keratosis pilaris (KP). Keratosis pilaris can be described in association with atopic dermatitis and ichthyosis, which were not present in our patient. The lesions usually present on the sides of the cheeks and lateral region of the arms and legs. Compared with follicular keratosis, KP lesions usually present with associated perifollicular erythema. Our patient did not present with lesions on the cheeks or the sides of the arms or legs. Milia can present on the chin of children, usually if there is history of rubbing or trauma, or on a scar. Milia are micro keratin cysts, usually seen in areas of the face. Lichen spinulous is described as rough small follicular papules that present in oval or circular patches that can grow up to 5 cm and spread rapidly. They usually present on the extensor surfaces of the extremities, neck, abdomen, and knees. These lesions are thought to be secondary to infections, have been associated with atopy, and have been seen in patients with atopic dermatitis. There is a probable genetic predisposition. The lesions are usually treated with gentle soaps and moisturizer containing keratolytics like urea or salicylic acid, and in some cases topical retinoids can also be tried. Follicular mucinosis can also present similarly to keratosis follicularis. The lesions present as scaly plaques or as grouped skin color papules on the face, scalp, or the neck that can also be associated with hair loss. Sometimes a biopsy needs to be done to be able to distinguish it from follicular keratosis. There is an increase of mucin around hair follicles and sebaceous glands with associated inflammation and degeneration of the follicular structures. In patients with primary follicular mucinosis the lesions can resolve spontaneously in a couple of years. Lesions can be treated with topical corticosteroids, oral antibiotics like macrolides or tetracyclines, dapsone, and phototherapy.

KFC can be treated with vitamin D analogues. It is usually unresponsive to corticosteroids, keratolytic lotions, and retinoids. Our patient was prescribed calcipotriene.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego

References

1. Kanzaki T et al. J Am Acad Dermatol. 1992;26(1):134-5.

2. Buechner AA et al. JAMA Dermatol. 2018 Jan 1;154(1):111-2.

The bacterial, fungal, and atypical mycobacterial cultures from the lesions performed at the emergency department were all negative.

Pediatric dermatology was consulted and a punch biopsy of one of the lesions was done. Histopathologic examination showed a mixed perifollicular infiltrate of predominantly eosinophils with some neutrophils and associated microabscesses. Periodic acid Schiff and Fite stains failed to reveal any organisms. CD1 immunostain was negative. Fresh tissue cultures for bacteria, fungi, and atypical mycobacteria were negative.

Given the clinical presentation of chronic recurrent sterile pustules on an infant with associated eosinophilia and the reported histopathologic findings, the patient was diagnosed with eosinophilic pustular folliculitis of infancy (EPFI).

162996_photo1_web.jpg

EPFI is a rare and idiopathic cutaneous disorder present in children. About 70% of the cases reported occur in the first 6 month of life and rarely present past 3 years of age. EPF encompasses a group of conditions including the classic adult form, or Ofuji disease. EPF is seen in immunosuppressed patients, mainly HIV positive, and EPF is also seen in infants and children.

In EPFI, males are most commonly affected. The condition presents, as it did in our patient, with recurrent crops of sterile papules and pustules mainly on the scalp, but they can occur in other parts of the body. The lesions go away within a few weeks to months without leaving any scars but it can take months to years to resolve. Histopathologic analysis of the lesions show an eosinophilic infiltrate which can be follicular, perifollicular, or periadnexal with associated flame figures in about 26% of cases.

Aggressive treatment is usually not needed as lesions are self-limited. Lesions can be treated with topical corticosteroids and oral antihistamine medications like cetirizine if symptomatic.

If the lesions start to present during the neonatal period, one may consider in the differential diagnosis, neonatal rashes like transient neonatal pustular melanosis and erythema toxicum neonatorum. Both of these neonatal conditions tend to resolve in the first month of life, compared with EPFI where lesions can come and go for months to years. EPFI lesions can be described as pustules and inflammatory papules, as well as furuncles and vesicles. All of the lesions may be seen in one patient at one time, which will not be typical for transient neonatal pustular melanosis or erythema toxicum. Eosinophils can be seen in erythema toxicum but folliculitis is not present. The inflammatory infiltrate seen in transient neonatal pustular melanosis is polymorphonuclear, not eosinophilic.

Early in the presentation, infectious conditions like staphylococcal or streptococcal folliculitis, cellulitis and furunculosis, tinea capitis, atypical mycobacterial infections, herpes simplex, and parasitic infections like scabies should be considered. In young infants, empiric antibiotic treatment may be started until cultures are finalized. If there is a family history of pruritic papules and pustules, scabies should be considered. A scabies prep can be done to rule out this entity.

Langerhans cell histiocytosis can also present with pustules and papules in early infancy and also has a predilection for the scalp. When this condition is in question, a skin biopsy should be performed which shows a CD1 positive histiocytic infiltrate.

In conclusion, EPFI is a benign rare condition that can present in infants as recurrent pustules and papules, mainly on the scalp, which are self-limited and if symptomatic can be treated with topical corticosteroids and antihistamines.
 

References

Alonso-Castro L et al. Dermatol Online J. 2012 Oct 15;18(10):6.

Frølunde AS et al. Clin Case Rep. 2021 May 11;9(5):e04167.

Hernández-Martín Á et al. J Am Acad Dermatol. 2013 Jan;68(1):150-5.

The bacterial, fungal, and atypical mycobacterial cultures from the lesions performed at the emergency department were all negative.

Pediatric dermatology was consulted and a punch biopsy of one of the lesions was done. Histopathologic examination showed a mixed perifollicular infiltrate of predominantly eosinophils with some neutrophils and associated microabscesses. Periodic acid Schiff and Fite stains failed to reveal any organisms. CD1 immunostain was negative. Fresh tissue cultures for bacteria, fungi, and atypical mycobacteria were negative.

Given the clinical presentation of chronic recurrent sterile pustules on an infant with associated eosinophilia and the reported histopathologic findings, the patient was diagnosed with eosinophilic pustular folliculitis of infancy (EPFI).

162996_photo1_web.jpg

EPFI is a rare and idiopathic cutaneous disorder present in children. About 70% of the cases reported occur in the first 6 month of life and rarely present past 3 years of age. EPF encompasses a group of conditions including the classic adult form, or Ofuji disease. EPF is seen in immunosuppressed patients, mainly HIV positive, and EPF is also seen in infants and children.

In EPFI, males are most commonly affected. The condition presents, as it did in our patient, with recurrent crops of sterile papules and pustules mainly on the scalp, but they can occur in other parts of the body. The lesions go away within a few weeks to months without leaving any scars but it can take months to years to resolve. Histopathologic analysis of the lesions show an eosinophilic infiltrate which can be follicular, perifollicular, or periadnexal with associated flame figures in about 26% of cases.

Aggressive treatment is usually not needed as lesions are self-limited. Lesions can be treated with topical corticosteroids and oral antihistamine medications like cetirizine if symptomatic.

If the lesions start to present during the neonatal period, one may consider in the differential diagnosis, neonatal rashes like transient neonatal pustular melanosis and erythema toxicum neonatorum. Both of these neonatal conditions tend to resolve in the first month of life, compared with EPFI where lesions can come and go for months to years. EPFI lesions can be described as pustules and inflammatory papules, as well as furuncles and vesicles. All of the lesions may be seen in one patient at one time, which will not be typical for transient neonatal pustular melanosis or erythema toxicum. Eosinophils can be seen in erythema toxicum but folliculitis is not present. The inflammatory infiltrate seen in transient neonatal pustular melanosis is polymorphonuclear, not eosinophilic.

Early in the presentation, infectious conditions like staphylococcal or streptococcal folliculitis, cellulitis and furunculosis, tinea capitis, atypical mycobacterial infections, herpes simplex, and parasitic infections like scabies should be considered. In young infants, empiric antibiotic treatment may be started until cultures are finalized. If there is a family history of pruritic papules and pustules, scabies should be considered. A scabies prep can be done to rule out this entity.

Langerhans cell histiocytosis can also present with pustules and papules in early infancy and also has a predilection for the scalp. When this condition is in question, a skin biopsy should be performed which shows a CD1 positive histiocytic infiltrate.

In conclusion, EPFI is a benign rare condition that can present in infants as recurrent pustules and papules, mainly on the scalp, which are self-limited and if symptomatic can be treated with topical corticosteroids and antihistamines.
 

References

Alonso-Castro L et al. Dermatol Online J. 2012 Oct 15;18(10):6.

Frølunde AS et al. Clin Case Rep. 2021 May 11;9(5):e04167.

Hernández-Martín Á et al. J Am Acad Dermatol. 2013 Jan;68(1):150-5.

The bacterial, fungal, and atypical mycobacterial cultures from the lesions performed at the emergency department were all negative.

Pediatric dermatology was consulted and a punch biopsy of one of the lesions was done. Histopathologic examination showed a mixed perifollicular infiltrate of predominantly eosinophils with some neutrophils and associated microabscesses. Periodic acid Schiff and Fite stains failed to reveal any organisms. CD1 immunostain was negative. Fresh tissue cultures for bacteria, fungi, and atypical mycobacteria were negative.

Given the clinical presentation of chronic recurrent sterile pustules on an infant with associated eosinophilia and the reported histopathologic findings, the patient was diagnosed with eosinophilic pustular folliculitis of infancy (EPFI).

162996_photo1_web.jpg

EPFI is a rare and idiopathic cutaneous disorder present in children. About 70% of the cases reported occur in the first 6 month of life and rarely present past 3 years of age. EPF encompasses a group of conditions including the classic adult form, or Ofuji disease. EPF is seen in immunosuppressed patients, mainly HIV positive, and EPF is also seen in infants and children.

In EPFI, males are most commonly affected. The condition presents, as it did in our patient, with recurrent crops of sterile papules and pustules mainly on the scalp, but they can occur in other parts of the body. The lesions go away within a few weeks to months without leaving any scars but it can take months to years to resolve. Histopathologic analysis of the lesions show an eosinophilic infiltrate which can be follicular, perifollicular, or periadnexal with associated flame figures in about 26% of cases.

Aggressive treatment is usually not needed as lesions are self-limited. Lesions can be treated with topical corticosteroids and oral antihistamine medications like cetirizine if symptomatic.

If the lesions start to present during the neonatal period, one may consider in the differential diagnosis, neonatal rashes like transient neonatal pustular melanosis and erythema toxicum neonatorum. Both of these neonatal conditions tend to resolve in the first month of life, compared with EPFI where lesions can come and go for months to years. EPFI lesions can be described as pustules and inflammatory papules, as well as furuncles and vesicles. All of the lesions may be seen in one patient at one time, which will not be typical for transient neonatal pustular melanosis or erythema toxicum. Eosinophils can be seen in erythema toxicum but folliculitis is not present. The inflammatory infiltrate seen in transient neonatal pustular melanosis is polymorphonuclear, not eosinophilic.

Early in the presentation, infectious conditions like staphylococcal or streptococcal folliculitis, cellulitis and furunculosis, tinea capitis, atypical mycobacterial infections, herpes simplex, and parasitic infections like scabies should be considered. In young infants, empiric antibiotic treatment may be started until cultures are finalized. If there is a family history of pruritic papules and pustules, scabies should be considered. A scabies prep can be done to rule out this entity.

Langerhans cell histiocytosis can also present with pustules and papules in early infancy and also has a predilection for the scalp. When this condition is in question, a skin biopsy should be performed which shows a CD1 positive histiocytic infiltrate.

In conclusion, EPFI is a benign rare condition that can present in infants as recurrent pustules and papules, mainly on the scalp, which are self-limited and if symptomatic can be treated with topical corticosteroids and antihistamines.
 

References

Alonso-Castro L et al. Dermatol Online J. 2012 Oct 15;18(10):6.

Frølunde AS et al. Clin Case Rep. 2021 May 11;9(5):e04167.

Hernández-Martín Á et al. J Am Acad Dermatol. 2013 Jan;68(1):150-5.

The patient was diagnosed with lichen nitidus, given the characteristic clinical presentation.

Lichen nitidus is a rare chronic inflammatory condition of the skin that most commonly presents in children and young adults and does not seem to be restricted to any sex or race. The classic lesions are described as asymptomatic to slightly pruritic, small (1 mm), skin-colored to hypopigmented flat-topped papules.

Koebner phenomenon is usually seen in which the skin lesions appear in areas of traumatized healthy skin. The extremities, abdomen, chest, and penis are common locations for the lesions to occur. Rarely, the oral mucosa or nails can be involved. It has been described in patients with a diagnosis of Crohn’s disease, Niemann-Pick disease, Down syndrome, and HIV. The rare, generalized purpuric variant has been reported in a few cases associated with interferon and ribavirin treatment for hepatitis C infection and nivolumab treatment for cancer. The pathophysiology of lichen nitidus is unknown.

Lichen nitidus can occur in the presence of other skin conditions like lichen planus, atopic dermatitis, vitiligo, erythema nodosum, and lichen spinulosus. Histopathologic characteristics of lichen nitidus are described as a “ball and claw” of epidermal rete around a lymphohistiocytic infiltrate. Parakeratosis overlying epidermal atrophy and focal basal liquefaction degeneration is also seen.

The differential diagnosis of lichen nitidus includes flat warts, which can present as clusters of small flat-topped papules that can show a pseudo-Koebner phenomenon (where the virus is seeded in traumatized skin). The morphological difference between the condition is that lichen nitidus lesions are usually monomorphic, compared with flat warts, which usually present with different sizes and shapes.

Matiz_Catalina_SanDiego.jpg

Patients with a history of allergic contact dermatitis may present with a generalized monomorphic eruption of skin-colored papules (known as ID reaction) that can sometimes be very similar to lichen nitidus. Allergic contact dermatitis tends to respond fairly quickly to topical or systemic corticosteroids, unlike lichen nitidus. There are a few reports that consider lichen nitidus to be a variant of lichen planus, although they have different histopathologic findings. Lichen planus lesions are described as polygonal, pruritic, purple to pink papules most commonly seen on the wrists, lower back, and ankles. Lichen planus can be seen in patients with hepatitis C and may also occur secondary to medication.

Milia are small keratin cysts on the skin that are commonly seen in babies as primary milia and can be seen in older children secondary to trauma (commonly on the eyelids) or medications. Given their size and monomorphic appearance, they can sometimes be confused with lichen nitidus.

Lichen nitidus is often asymptomatic and the lesions resolve within a few months to years. Topical corticosteroids can be helpful to alleviate the symptoms in patients who present with pruritus. In more persistent and generalized cases, phototherapy, systemic corticosteroids, acitretin, isotretinoin, or cyclosporine can be considered.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Chu J and Lam JM. CMAJ. 2014 Dec 9;186(18):E688.

Lestringant G et al. Dermatology 1996;192:171-3.

Peterson JA et al. Proc (Bayl Univ Med Cent). 2021 Aug 25;35(1):70-2.

Schwartz C and Goodman MB. “Lichen nitidus,” in StatPearls. Treasure Island, Fla.: StatPearls Publishing, 2022.

The patient was diagnosed with lichen nitidus, given the characteristic clinical presentation.

Lichen nitidus is a rare chronic inflammatory condition of the skin that most commonly presents in children and young adults and does not seem to be restricted to any sex or race. The classic lesions are described as asymptomatic to slightly pruritic, small (1 mm), skin-colored to hypopigmented flat-topped papules.

Koebner phenomenon is usually seen in which the skin lesions appear in areas of traumatized healthy skin. The extremities, abdomen, chest, and penis are common locations for the lesions to occur. Rarely, the oral mucosa or nails can be involved. It has been described in patients with a diagnosis of Crohn’s disease, Niemann-Pick disease, Down syndrome, and HIV. The rare, generalized purpuric variant has been reported in a few cases associated with interferon and ribavirin treatment for hepatitis C infection and nivolumab treatment for cancer. The pathophysiology of lichen nitidus is unknown.

Lichen nitidus can occur in the presence of other skin conditions like lichen planus, atopic dermatitis, vitiligo, erythema nodosum, and lichen spinulosus. Histopathologic characteristics of lichen nitidus are described as a “ball and claw” of epidermal rete around a lymphohistiocytic infiltrate. Parakeratosis overlying epidermal atrophy and focal basal liquefaction degeneration is also seen.

The differential diagnosis of lichen nitidus includes flat warts, which can present as clusters of small flat-topped papules that can show a pseudo-Koebner phenomenon (where the virus is seeded in traumatized skin). The morphological difference between the condition is that lichen nitidus lesions are usually monomorphic, compared with flat warts, which usually present with different sizes and shapes.

Matiz_Catalina_SanDiego.jpg

Patients with a history of allergic contact dermatitis may present with a generalized monomorphic eruption of skin-colored papules (known as ID reaction) that can sometimes be very similar to lichen nitidus. Allergic contact dermatitis tends to respond fairly quickly to topical or systemic corticosteroids, unlike lichen nitidus. There are a few reports that consider lichen nitidus to be a variant of lichen planus, although they have different histopathologic findings. Lichen planus lesions are described as polygonal, pruritic, purple to pink papules most commonly seen on the wrists, lower back, and ankles. Lichen planus can be seen in patients with hepatitis C and may also occur secondary to medication.

Milia are small keratin cysts on the skin that are commonly seen in babies as primary milia and can be seen in older children secondary to trauma (commonly on the eyelids) or medications. Given their size and monomorphic appearance, they can sometimes be confused with lichen nitidus.

Lichen nitidus is often asymptomatic and the lesions resolve within a few months to years. Topical corticosteroids can be helpful to alleviate the symptoms in patients who present with pruritus. In more persistent and generalized cases, phototherapy, systemic corticosteroids, acitretin, isotretinoin, or cyclosporine can be considered.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Chu J and Lam JM. CMAJ. 2014 Dec 9;186(18):E688.

Lestringant G et al. Dermatology 1996;192:171-3.

Peterson JA et al. Proc (Bayl Univ Med Cent). 2021 Aug 25;35(1):70-2.

Schwartz C and Goodman MB. “Lichen nitidus,” in StatPearls. Treasure Island, Fla.: StatPearls Publishing, 2022.

The patient was diagnosed with lichen nitidus, given the characteristic clinical presentation.

Lichen nitidus is a rare chronic inflammatory condition of the skin that most commonly presents in children and young adults and does not seem to be restricted to any sex or race. The classic lesions are described as asymptomatic to slightly pruritic, small (1 mm), skin-colored to hypopigmented flat-topped papules.

Koebner phenomenon is usually seen in which the skin lesions appear in areas of traumatized healthy skin. The extremities, abdomen, chest, and penis are common locations for the lesions to occur. Rarely, the oral mucosa or nails can be involved. It has been described in patients with a diagnosis of Crohn’s disease, Niemann-Pick disease, Down syndrome, and HIV. The rare, generalized purpuric variant has been reported in a few cases associated with interferon and ribavirin treatment for hepatitis C infection and nivolumab treatment for cancer. The pathophysiology of lichen nitidus is unknown.

Lichen nitidus can occur in the presence of other skin conditions like lichen planus, atopic dermatitis, vitiligo, erythema nodosum, and lichen spinulosus. Histopathologic characteristics of lichen nitidus are described as a “ball and claw” of epidermal rete around a lymphohistiocytic infiltrate. Parakeratosis overlying epidermal atrophy and focal basal liquefaction degeneration is also seen.

The differential diagnosis of lichen nitidus includes flat warts, which can present as clusters of small flat-topped papules that can show a pseudo-Koebner phenomenon (where the virus is seeded in traumatized skin). The morphological difference between the condition is that lichen nitidus lesions are usually monomorphic, compared with flat warts, which usually present with different sizes and shapes.

Patients with a history of allergic contact dermatitis may present with a generalized monomorphic eruption of skin-colored papules (known as ID reaction) that can sometimes be very similar to lichen nitidus. Allergic contact dermatitis tends to respond fairly quickly to topical or systemic corticosteroids, unlike lichen nitidus. There are a few reports that consider lichen nitidus to be a variant of lichen planus, although they have different histopathologic findings. Lichen planus lesions are described as polygonal, pruritic, purple to pink papules most commonly seen on the wrists, lower back, and ankles. Lichen planus can be seen in patients with hepatitis C and may also occur secondary to medication.

Milia are small keratin cysts on the skin that are commonly seen in babies as primary milia and can be seen in older children secondary to trauma (commonly on the eyelids) or medications. Given their size and monomorphic appearance, they can sometimes be confused with lichen nitidus.

Lichen nitidus is often asymptomatic and the lesions resolve within a few months to years. Topical corticosteroids can be helpful to alleviate the symptoms in patients who present with pruritus. In more persistent and generalized cases, phototherapy, systemic corticosteroids, acitretin, isotretinoin, or cyclosporine can be considered.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.

References

Chu J and Lam JM. CMAJ. 2014 Dec 9;186(18):E688.

Lestringant G et al. Dermatology 1996;192:171-3.

Peterson JA et al. Proc (Bayl Univ Med Cent). 2021 Aug 25;35(1):70-2.

Schwartz C and Goodman MB. “Lichen nitidus,” in StatPearls. Treasure Island, Fla.: StatPearls Publishing, 2022.

A biopsy of the edge of one of lesions on the torso was performed. Histopathology demonstrated hyperkeratosis of the stratum corneum with focal thickening of the granular cell layer, basal layer degeneration of the epidermis, and a band-like subepidermal lymphocytic infiltrate with Civatte bodies consistent with lichen planus. There was some reduction in the elastic fibers on the papillary dermis.

161428_Picture2_web.jpg

Given the morphology of the lesions and the histopathologic presentation, he was diagnosed with annular atrophic lichen planus (AALP). Lichen planus is a chronic inflammatory condition that can affect the skin, nails, hair, and mucosa. Lichen planus is seen in less than 1% of the population, occurring mainly in middle-aged adults and rarely seen in children. Though, there appears to be no clear racial predilection, a small study in the United States showed a higher incidence of lichen planus in Black children. Lesions with classic characteristics are pruritic, polygonal, violaceous, flat-topped papules and plaques.

There are different subtypes of lichen planus, which include papular or classic form, hypertrophic, vesiculobullous, actinic, annular, atrophic, annular atrophic, linear, follicular, lichen planus pigmentosus, lichen pigmentosa pigmentosus-inversus, lichen planus–lupus erythematosus overlap syndrome, and lichen planus pemphigoides. The annular atrophic form is the least common of all, and there are few reports in the pediatric population. AALP presents as annular papules and plaques with atrophic centers that resolve within a few months leaving postinflammatory hypo- or hyperpigmentation and, in some patients, permanent atrophic scarring.

In histopathology, the lesions show the classic characteristics of lichen planus including vacuolar interface changes and necrotic keratinocytes, hypergranulosis, band-like infiltrate in the dermis, melanin incontinence, and Civatte bodies. In AALP, the center of the lesion shows an atrophic epidermis, and there is also a characteristic partial reduction to complete destruction of elastic fibers in the papillary dermis in the center of the lesion and sometimes in the periphery as well, which helps differentiate AALP from other forms of lichen planus.

The differential diagnosis for AALP includes tinea corporis, which can present with annular lesions, but they are usually scaly and rarely resolve on their own. Pityriasis rosea lesions can also look very similar to AALP lesions, but the difference is the presence of an inner collaret of scale and a lack of atrophy in pityriasis rosea. Pityriasis rosea is a rash that can be triggered by viral infections, medications, and vaccines and self-resolves within 10-12 weeks. Secondary syphilis can also be annular and resemble lesions of AALP. Syphilis patients are usually sexually active and may have lesions present on the palms and soles, which were not seen in our patient.

Granuloma annulare should also be included in the differential diagnosis of AALP. Granuloma annulare lesions present as annular papules or plaques with raised borders and a slightly hyperpigmented center that may appear more depressed compared to the edges of the lesion, though not atrophic as seen in AALP. Pityriasis lichenoides chronica is an inflammatory condition of the skin in which patients present with erythematous to brown papules in different stages which may have a mica-like scale, usually not seen on AALP. Sometimes a skin biopsy will be needed to differentiate between these conditions.

It is very important to make a timely diagnosis of AALP and treat the lesions early as it may leave long-lasting dyspigmentation and scarring. Though AAPL lesions can be resistant to treatment with topical medications, there are reports of improvement with superpotent topical corticosteroids and calcineurin inhibitors. In recalcitrant cases, systemic therapy with isotretinoin, acitretin, methotrexate, systemic corticosteroids, dapsone, and hydroxychloroquine can be considered. Our patient was treated with clobetasol propionate ointment 0.05% with good response.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.
 

References

Bowers S and Warshaw EM. J Am Acad Dermatol. 2006 Oct;55(4):557-72; quiz 573-6.

Gorouhi F et al. Scientific World Journal. 2014 Jan 30;2014:742826.

Santhosh P and George M. Int J Dermatol. 2022.61:1213-7.

Sears S et al. Pediatr Dermatol. 2021;38:1283-7.

Weston G and Payette M. Int J Womens Dermatol. 2015 Sep 16;1(3):140-9.

A biopsy of the edge of one of lesions on the torso was performed. Histopathology demonstrated hyperkeratosis of the stratum corneum with focal thickening of the granular cell layer, basal layer degeneration of the epidermis, and a band-like subepidermal lymphocytic infiltrate with Civatte bodies consistent with lichen planus. There was some reduction in the elastic fibers on the papillary dermis.

161428_Picture2_web.jpg

Given the morphology of the lesions and the histopathologic presentation, he was diagnosed with annular atrophic lichen planus (AALP). Lichen planus is a chronic inflammatory condition that can affect the skin, nails, hair, and mucosa. Lichen planus is seen in less than 1% of the population, occurring mainly in middle-aged adults and rarely seen in children. Though, there appears to be no clear racial predilection, a small study in the United States showed a higher incidence of lichen planus in Black children. Lesions with classic characteristics are pruritic, polygonal, violaceous, flat-topped papules and plaques.

There are different subtypes of lichen planus, which include papular or classic form, hypertrophic, vesiculobullous, actinic, annular, atrophic, annular atrophic, linear, follicular, lichen planus pigmentosus, lichen pigmentosa pigmentosus-inversus, lichen planus–lupus erythematosus overlap syndrome, and lichen planus pemphigoides. The annular atrophic form is the least common of all, and there are few reports in the pediatric population. AALP presents as annular papules and plaques with atrophic centers that resolve within a few months leaving postinflammatory hypo- or hyperpigmentation and, in some patients, permanent atrophic scarring.

In histopathology, the lesions show the classic characteristics of lichen planus including vacuolar interface changes and necrotic keratinocytes, hypergranulosis, band-like infiltrate in the dermis, melanin incontinence, and Civatte bodies. In AALP, the center of the lesion shows an atrophic epidermis, and there is also a characteristic partial reduction to complete destruction of elastic fibers in the papillary dermis in the center of the lesion and sometimes in the periphery as well, which helps differentiate AALP from other forms of lichen planus.

The differential diagnosis for AALP includes tinea corporis, which can present with annular lesions, but they are usually scaly and rarely resolve on their own. Pityriasis rosea lesions can also look very similar to AALP lesions, but the difference is the presence of an inner collaret of scale and a lack of atrophy in pityriasis rosea. Pityriasis rosea is a rash that can be triggered by viral infections, medications, and vaccines and self-resolves within 10-12 weeks. Secondary syphilis can also be annular and resemble lesions of AALP. Syphilis patients are usually sexually active and may have lesions present on the palms and soles, which were not seen in our patient.

Granuloma annulare should also be included in the differential diagnosis of AALP. Granuloma annulare lesions present as annular papules or plaques with raised borders and a slightly hyperpigmented center that may appear more depressed compared to the edges of the lesion, though not atrophic as seen in AALP. Pityriasis lichenoides chronica is an inflammatory condition of the skin in which patients present with erythematous to brown papules in different stages which may have a mica-like scale, usually not seen on AALP. Sometimes a skin biopsy will be needed to differentiate between these conditions.

It is very important to make a timely diagnosis of AALP and treat the lesions early as it may leave long-lasting dyspigmentation and scarring. Though AAPL lesions can be resistant to treatment with topical medications, there are reports of improvement with superpotent topical corticosteroids and calcineurin inhibitors. In recalcitrant cases, systemic therapy with isotretinoin, acitretin, methotrexate, systemic corticosteroids, dapsone, and hydroxychloroquine can be considered. Our patient was treated with clobetasol propionate ointment 0.05% with good response.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.
 

References

Bowers S and Warshaw EM. J Am Acad Dermatol. 2006 Oct;55(4):557-72; quiz 573-6.

Gorouhi F et al. Scientific World Journal. 2014 Jan 30;2014:742826.

Santhosh P and George M. Int J Dermatol. 2022.61:1213-7.

Sears S et al. Pediatr Dermatol. 2021;38:1283-7.

Weston G and Payette M. Int J Womens Dermatol. 2015 Sep 16;1(3):140-9.

A biopsy of the edge of one of lesions on the torso was performed. Histopathology demonstrated hyperkeratosis of the stratum corneum with focal thickening of the granular cell layer, basal layer degeneration of the epidermis, and a band-like subepidermal lymphocytic infiltrate with Civatte bodies consistent with lichen planus. There was some reduction in the elastic fibers on the papillary dermis.

161428_Picture2_web.jpg

Given the morphology of the lesions and the histopathologic presentation, he was diagnosed with annular atrophic lichen planus (AALP). Lichen planus is a chronic inflammatory condition that can affect the skin, nails, hair, and mucosa. Lichen planus is seen in less than 1% of the population, occurring mainly in middle-aged adults and rarely seen in children. Though, there appears to be no clear racial predilection, a small study in the United States showed a higher incidence of lichen planus in Black children. Lesions with classic characteristics are pruritic, polygonal, violaceous, flat-topped papules and plaques.

There are different subtypes of lichen planus, which include papular or classic form, hypertrophic, vesiculobullous, actinic, annular, atrophic, annular atrophic, linear, follicular, lichen planus pigmentosus, lichen pigmentosa pigmentosus-inversus, lichen planus–lupus erythematosus overlap syndrome, and lichen planus pemphigoides. The annular atrophic form is the least common of all, and there are few reports in the pediatric population. AALP presents as annular papules and plaques with atrophic centers that resolve within a few months leaving postinflammatory hypo- or hyperpigmentation and, in some patients, permanent atrophic scarring.

In histopathology, the lesions show the classic characteristics of lichen planus including vacuolar interface changes and necrotic keratinocytes, hypergranulosis, band-like infiltrate in the dermis, melanin incontinence, and Civatte bodies. In AALP, the center of the lesion shows an atrophic epidermis, and there is also a characteristic partial reduction to complete destruction of elastic fibers in the papillary dermis in the center of the lesion and sometimes in the periphery as well, which helps differentiate AALP from other forms of lichen planus.

The differential diagnosis for AALP includes tinea corporis, which can present with annular lesions, but they are usually scaly and rarely resolve on their own. Pityriasis rosea lesions can also look very similar to AALP lesions, but the difference is the presence of an inner collaret of scale and a lack of atrophy in pityriasis rosea. Pityriasis rosea is a rash that can be triggered by viral infections, medications, and vaccines and self-resolves within 10-12 weeks. Secondary syphilis can also be annular and resemble lesions of AALP. Syphilis patients are usually sexually active and may have lesions present on the palms and soles, which were not seen in our patient.

Granuloma annulare should also be included in the differential diagnosis of AALP. Granuloma annulare lesions present as annular papules or plaques with raised borders and a slightly hyperpigmented center that may appear more depressed compared to the edges of the lesion, though not atrophic as seen in AALP. Pityriasis lichenoides chronica is an inflammatory condition of the skin in which patients present with erythematous to brown papules in different stages which may have a mica-like scale, usually not seen on AALP. Sometimes a skin biopsy will be needed to differentiate between these conditions.

It is very important to make a timely diagnosis of AALP and treat the lesions early as it may leave long-lasting dyspigmentation and scarring. Though AAPL lesions can be resistant to treatment with topical medications, there are reports of improvement with superpotent topical corticosteroids and calcineurin inhibitors. In recalcitrant cases, systemic therapy with isotretinoin, acitretin, methotrexate, systemic corticosteroids, dapsone, and hydroxychloroquine can be considered. Our patient was treated with clobetasol propionate ointment 0.05% with good response.

Dr. Matiz is a pediatric dermatologist at Southern California Permanente Medical Group, San Diego.
 

References

Bowers S and Warshaw EM. J Am Acad Dermatol. 2006 Oct;55(4):557-72; quiz 573-6.

Gorouhi F et al. Scientific World Journal. 2014 Jan 30;2014:742826.

Santhosh P and George M. Int J Dermatol. 2022.61:1213-7.

Sears S et al. Pediatr Dermatol. 2021;38:1283-7.

Weston G and Payette M. Int J Womens Dermatol. 2015 Sep 16;1(3):140-9.