The FP diagnosed seborrheic dermatitis, which can cause erythema and greasy scale of the external ear and ear canal. The seborrheic dermatitis itself causes breaks in the skin and the coexisting pruritus may lead a patient to damage his or her ear canal while scratching with a Q-tip or other implement. Scratching in this manner also puts the patient at risk for a secondary infection. Fortunately, the patient in this case did not have a secondary infection.
Treatment for seborrhea anywhere on the skin or scalp involves decreasing the Malassezia overgrowth with antifungal agents and using a topical steroid to control the inflammation. Typical antifungal agents include dandruff shampoos with selenium sulfide, zinc pyrithione, or ketoconazole. Patients are directed to use the shampoo on their hair and scalp and then apply the lather to other affected areas such as the ears. It helps if this is done daily or every other day.
Low-potency topical steroids are sufficient to treat the inflammation of seborrhea in most cases. Studies show that desonide cream or lotion is a good choice for seborrheic dermatitis. Topical antifungal creams including the azoles may also be used, if needed.
This patient was treated with OTC selenium sulfide shampoo and topical desonide lotion with good results.
Photos courtesy of Dr. Eric Kraus and text for Photo Rounds Friday courtesy of Richard P. Usatine, MD. This case was adapted from: Rayala B. Otitis externa. In: Usatine R, Smith M, Mayeaux EJ, et al, eds. Color Atlas of Family Medicine. 2nd ed. New York, NY: McGraw-Hill; 2013:180-184.
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