Allergic contact dermatitis from chironomids.

Although Type I allergy to chironomids is well-known, allergic contact dermatitis caused by these cosmopolitan insects has not previously been reported. In the case we describe in this report, patch tests disclosed a delayed-type hypersensitivity to 4 different species of chironomids (larvae of Chironomus thummi, Chironomus plumosus, and 2 different species of Glyptotendipes) as the probable cause of airborne facial contact dermatitis. An additional asymptomatic immediate-type allergy to chironomids was demonstrated by scratch tests and specific IgE. The possible sources of exposure to chironomids, their allergens and their distribution are discussed with regard to clinical implications.