[Yellowish psoriasis revealing dermal lipomatous metaplasia]

Dermal lipomatous metaplasia is a particular histological presentation characterized by the presence of mature fat cells in the dermis. It is found in the tissue stroma of certain skin tumours and in a single reported case of psoriasis, imparting an orange-yellow tint. Herein we report a second case of this type.

An 82-year-old woman was consulting for an extensive, rapidly spreading psoriasis flare-up that had appeared 3 months earlier. Her psoriasis had been present for 30 years and had rarely been treated. The clinical examination revealed orange-yellow patches, either alone or mixed with psoriasis plaques. The laboratory lipid balance was without abnormalities. Protein electrophoresis revealed chronic inflammation. Histopathology and immunohistochemistry findings supported the diagnosis of dermal lipomatous metaplasia. Acitretin 20mg/day produced marked improvement in the rash within one month.

Dermal lipomatous metaplasia is a highly specific and rare entity that should be considered where orange-yellow lesions are seen.