Hyperpigmentation-Ashy Dermatosis

Abstract

Ashy dermatosis-like hyperpigmentation Erythema dyschromicum perstans (EDP), also known as ashy dermatosis, is a hypermelanotic condition characterised by the development of a slate-grey macula in otherwise healthy individuals. Here, we describe sudden-onset EDP in a 19-year-old male patient.His lesions had started 3 months ago and increased in the last 2 weeks. Dermatological examination revealed pigmented macules and patches of different sizes, which tended to coalesce, on the back and anterior aspect of the trunk. The lesions did not regress after local treatment with a prescribed corticosteroid cream of moderate potency. The patient was free from systemic disease, was not taking any drugs and had no relevant family history. Histopathological examination of lesional biopsy tissue from the back and anterior of the trunk revealed EDP, characterised by vacuolar degeneration of the basal layer, mild lymphohistiocytic inflammatory cell infiltration around the vessels in the upper dermis, melanophages, pigment incontinence, and low-level lymphocyte exocytosis in the epithelium. Dapsone (100 mg/day) controlled the lesions. EDP is a rare dermatosis, for which differential diagnosis and treatment may thus sometimes be inadequate.