Current Understanding of Seborrheic Dermatitis: Presentation, Diagnosis, and Special Populations.

Seborrheic dermatitis is a chronic inflammatory skin condition characterized by erythematous patches and plaques with white-to-yellow greasy scale often localized to the scalp and face. Its presentation varies between children and adults, as well as across different skin tones. Notably, in patients with more richly pigmented skin, postinflammatory pigment alteration can also be a feature of seborrheic dermatitis, highlighting the importance of considering skin colour differences in the diagnosis. Clinical manifestations of seborrheic dermatitis can overlap with several other dermatoses, including atopic dermatitis, psoriasis, and rosacea, thereby necessitating careful evaluation for accurate diagnosis. The pathophysiology of seborrheic dermatitis involves a complex interplay between dermatological, neurological, immunological, and microbiome-related factors. The multifaceted nature of seborrheic dermatitis underscores the need for a comprehensive approach to its diagnosis, considering age, skin colour, cultural practices, and comorbidities. This is the second in a series of 3 reviews, each addressing different aspects of seborrheic dermatitis, including its epidemiology, diagnosis, and treatment considerations.