Seborrheic Dermatitis: Diagnosis and Treatment

Overview / Definition Seborrheic dermatitis is a chronic inflammatory skin disorder that primarily affects the scalp, face, and upper body. It is characterized by erythematous patches with greasy, yellowish scales. While often seen in adults, it can also occur in infants as cradle cap. Epidemiology This condition is prevalent in the general population, with a higher incidence observed in: Adults aged 30-60 years Individuals with oily skin or hair Patients with neurological disorders, such as Parkinson's disease HIV/AIDS patients Infants (commonly as cradle cap) Overall, seborrheic dermatitis affects approximately 3-5% of the general population. Pathophysiology / Mechanism The exact cause of seborrheic dermatitis is not completely understood, but it is believed to involve: Malassezia yeast: Overgrowth of this fungus on the skin may trigger an inflammatory response. Sebum production: Increased sebum production may provide a favorable environment for Malassezia. Immune response: An abnormal immune response to the yeast and other environmental factors contributes to inflammation. Genetics and environmental factors may also play a role in the disease's development. Clinical Presentation Patients typically present with: Erythematous patches with greasy, yellowish scales Itching, which can be mild to moderate Locations: scalp (dandruff), face (nasolabial folds, eyebrows), chest, and back In infants: thick, crusted lesions on the scalp (cradle cap) Symptoms may worsen with stress, cold weather, or hormonal changes. Diagnosis / Workup The diagnosis of seborrheic dermatitis is primarily clinical, based on history and physical examination. However, differential diagnoses should be considered, including: Psoriasis Atopic dermatitis Contact dermatitis Tinea capitis Dermatophyte infections In cases where the diagnosis is uncertain, a skin scraping or biopsy may be performed to rule out other conditions. Treatment / Management Management of seborrheic dermatitis involves: Topical