The patient is a 68-year-old male presenting for treatment of a rash affecting his nasolabial folds, eyelashes, forehead, and scalp. He complains that the condition is itchy and unsightly and that it is most severe in the colder months. Medical history is positive for hypertension, cigarette smoking, and moderate alcohol use. Examination reveals erythema and scaling of the affected areas.
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Seborrheic dermatitis is a papulosquamous disorder common in the sebum-rich areas of the body, including the scalp, face, and upper trunk.1 The dermatitis can range from mild dandruff to severe exfoliative erythroderma. It has been linked to Malassezia, immunologic abnormalities, and activation of complement.2,3
Patients most frequently present with scaling and itching of the scalp with more extensive cases involving the forehead, nasolabial folds, ears, and chest. Improvement during the summer months is common. The dermatitis can vary from mild, patchy scaling to widespread, thick adherent crusts. The lesions on the skin appear as greasy scales over erythematous skin. In African Americans, the skin may become hypo-pigmented. A secondary infection should be considered if oozing or crusting is present.
The cause of seborrheic dermatitis is unclear; the improvement with antifungals suggests a relationship with Malassezia.3 The density of this microorganism correlates with disease severity.4 Seborrheic dermatitis of the scalp (dandruff) may respond to shampoos containing either tar, zinc, or ketoconazole. In addition to topical antifungals, low-potency topical steroids mitigate inflammation and are also effective.
Rebecca Geiger, PA-C, is a physician assistant on staff at the DermDox Dermatology Center in Hazleton, Pennsylvania. Stephen Schleicher, MD, is an associate professor of medicine at the Commonwealth Medical College in Scranton, Pennsylvania, and an adjunct assistant professor of dermatology at the Perelman School of Medicine at the University of Pennsylvania in Philadelphia.
- 1. Shi VY, Leo M, Hassoun L, Chahal DS, Maibach HI, Sivamani RK. Role of sebaceous glands in inflammatory dermatoses. J Am Acad Dermatol. 2015:73:856-863.
- 2. Handler MZ. Seborrheic dermatitis. Updated April 10, 2017. Accessed August 3, 2017. Available at: http://emedicine.medscape.com/article/1108312-overview
- 3. Kamamoto C, Nishikaku A, Fernandes F, et al. Malassezia yeasts in seborrheic dermatitis and seborrhea. J Am Acad Dermatol. 2016:74(Suppl 1):AB61.
- 4. Dessinioti C., Katsambas A. Seborrheic dermatitis: etiology, risk factors, and treatments: facts and controversies. Clin Dermatol. 2013;31:343-351.