Perioral dermatitis.

Perioral dermatitis is a relatively common inflammatory facial skin disorder that predominantly affects women. It is rarely diagnosed in children. A typical perioral dermatitis presentation involves the eruption of papules and pustules that may recur over weeks to months, occasionally with fine scales. The differential diagnosis includes seborrheic dermatitis, systemic lupus erythematosus, acne vulgaris, lupus miliaris disseminatus faciei, polymorphous light eruption, steroid-induced rosacea, granulomatous perioral dermatitis, contact dermatitis (allergic and irritant), and even basal cell carcinoma. The histopathology is similar to that of rosacea, with a perivascular and perifollicular lymphohistiocytic infiltrate and sebaceous hyperplasia. The etiology of perioral dermatitis is unknown, but the uncritical use of topical corticosteroids often precedes skin lesions. Physical sunscreens with high sun protection factors may cause perioral dermatitis in children.