[Perioral dermatitis--an allergic disease?].

Perioral dermatitis was diagnosed in 329 patients. Sparing a thin white strip round the red border of the lips erythemas with papules and pseudopustules are arising around the mouth, on nose, eyes, chin, forehead, cheeks and the lateral parts of the neck. The duration of the infection ranged from two weeks up to three years. In many patients the following allergens were detected by patch testing: cosmetics, dental pastes, washing powders, chloric water, mohair, synthetics, and flowers. In 80 patients demodex was discovered. Its role in the pathogenesis of perioral dermatitis is doubtful. Biopsis were taken from 10 patients. Treatment with liquid nitrogen gives good results while antibiotics and corticosteroids are of little effect.