Seborrhoeic Dermatitis

Abstract

Seborrhoeic dermatitis is a common, chronic, inflammatory dermatosis that has a predilection for the scalp, facial creases and large flexures including the ano‐genital area. It affects adults of all ages and often runs a relapsing course. A short‐lived infantile variant is also recognized. The cause is unclear, but increasing evidence supports a pathogenic role for lipophilic Malassezia yeasts, which comprise part of the normal skin microbiome. Most affected individuals are healthy, but seborrhoeic dermatitis may be a presenting feature of HIV infection, so at‐risk individuals should be tested. Treatment is aimed at reducing scalp yeasts and/or the inflammatory response, with topically applied imidazole antifungal drugs, mild potency corticosteroids and calcineurin antagonists.

The Role of Yeasts in Human Health: A Review

“…Fungi such as Malassezia is found in the sebaceous gland where lipids are the main source of energy. As this yeast is usually commensal, the mechanism that triggers this disease has been increasingly investigated [60]. Its DNA has been detected in about 90% of skin lesions; the skin lesions of atopic dermatitis and colonization increase with the severity of the disease [90].…”