Perioral (periorificial) dermatitis is a distinct clinical entity that can easily be confused with rosacea, seborrheic dermatitis, eczematous dermatitis, or acne. It primarily affects young women and is usually found around the mouth (Figs. 31-1 and 31-2) but occasionally around the nose or eyes. Pediatric cases are more common in boys. The underlying cause is unclear. Candida, Demodex, fluorinated toothpastes, chapping, irritation, and oral contraceptives have been implicated. As with rosacea, prolonged use of potent topical or inhaled corticosteroids can cause an eruption with similar features and can perpetuate preexisting disease.

Perioral (periorificial) dermatitis is found at a significantly increased rate in atopic individuals. Compared with patients with rosacea, those with perioral dermatitis have significantly increased transepidermal water loss and atopic diathesis.

Although often described as a variant of rosacea, perioral (periorificial) dermatitis is distinct. It may be distinguished by the absence of flushing or telangiectasias, the morphology and distribution of the papules, and its incidence in the pediatric population.

Discrete erythematous or flesh-colored papules and papulopustules are seen singly, in clusters, or in confluent plaques around the mouth, sparing of a 3- to 5-mm zone below the vermillion border. Lesions may occasionally occur around the nose and on the malar areas below and lateral to the eyes. Pediatric patients particularly may have periocular and perinasal papules. In 10% to 20% of patients, the disease will extend to the glabella and the periocular region. There is often a persistent erythema of the nasolabial folds that may extend around the mouth and onto the chin. Long-standing lesions show a flatter, more confluent eruption, with superimposed dry scaling. The differential diagnosis includes seborrheic dermatitis, acne, rosacea, contact or irritant dermatitis, nutritional deficiencies, or the rare glucagonoma syndrome (Table 31-1).

The diagnosis of perioral dermatitis is usually made with clinical observation. No specific laboratory testing is indicated. Skin biopsy is rarely needed, but would most commonly demonstrate similar findings to rosacea.