Chironomids are insects which inhabit wetlands. In countries such as Sudan, The United States, Egypt and Japan they are the cause of serious environmental allergy.
In Europe, and particularly in Spain, allergy to Chironomids is infrequent and has only been described in patients who handle Chironomid larvae which form part of certain fish foods.

Materials and methods: We report a case of hypersensitivity to the Chironomid Midge (Chironomus thummi thummi) in a 23-year-old patient who on two occasions, after being in contact with fishfood, suffered rash, rhinoconjunctivitis, dyspnea and dysphagia.
A Prick test was carried out with the habitual pneumoallergens, Chironomid Midge extract (PBS: 1.3 mg/ml), Common Mosquito (Culex pipiens), Squid, Mussel, Prawn and Anisakis. Conjunctival provocation was also carried out with Chironomid Midge extract; detection of specific IgE for Chironomid Midge, Common Mosquito (Aedes comunis), Mussel, Squid, Shrimp, Anisakis, house dust and house mites by means of the CAP technique; detection of IgE by means of ELISA in response to Chironomid Midge, Aedes mosquito, Squid, Prawn, Mussel and Anisakis; ELISA-inhibition and Immunoblott-inhibition.

Results: The positive results of the cutaneous tests, the detection of specific IgE and conjunctival provocation confirmed the existence of an IgE-mediated mechanism. In our patient, the in vitro techniques demonstrated cross reactivity with the Common Mosquito.

Conclusions: We report on a patient with a case history of rhinoconjunctivitis, rash, dyspnea, and dysphagia after handling fish food. The etiological agent was the Chironomid larvae. The sensitization of our patient has been demonstrated by means of in vivo and in vitro techniques.

Key words: Chironomids, allergy to insects, chironomid midge, fish food, cutaneous test.