Lichen amyloidosis in a dark skinned patient
R De Pasquale1, R Caltabiano, F Dinotta
1Department of Dermatology, University of Catania, G. Rodolico Polyclinic, Catania, Italy. dermorocco@libero.it
Summary
Lichen amyloidosis, a skin condition causing itchy bumps, was observed in a dark-skinned patient. Biopsy confirmed amyloid deposits in the dermis, characteristic of this localized cutaneous amyloidosis.
Area of Science:
- Dermatology
- Pathology
Background:
- Lichen amyloidosis is a primary localized cutaneous amyloidosis.
- It presents as a persistent, pruritic eruption of hyperkeratotic papules.
- The exact cause is unknown, with chronic skin irritation being a potential factor.
Observation:
- A typical case in a dark-skinned patient is reported.
- Physical examination showed shiny, brownish papules on the legs.
- No associated macular lesions were present.
Findings:
- Biopsy revealed amorphous, eosinophilic deposits in the dermis.
- These deposits stained positively with Congo red, confirming amyloid presence.
- Amyloid exhibited apple-green birefringence under polarized light.
Implications:
- This case highlights lichen amyloidosis presentation in diverse skin tones.
- Confirms diagnostic criteria for lichen amyloidosis through histopathology.
- Contributes to understanding localized cutaneous amyloidosis.
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