Allergy to asticot maggots. Identification of allergens

There are some written reports of allergic reactions after contact with Asticot larvae in anglers and occupationally exposed workers. Clinical and immunological studies were performed to confirm the allergens involved in the case of a 12-year-old male who developed respiratory symptoms shortly after contact with Asticot maggots used as fish bait.

Aqueous extracts of Asticot maggots were taken for in vivo and in vitro tests. The protein concentration as determined by turbidimetric assay was 1.4 mg/ml. Skin prick test with Asticot extract was positive with an immediate response. Ten atopic and ten nonatopic control subjects did not react to the extract. Specific serum IgE antibodies against Asticot were found in the patient's serum (ELISA). Coomasie staining after SDS-PAGE separation of Asticot extract showed three protein bands of 30, 40 and 60 kDa. IgE immunoblot showed one antigenic band of 60 kDa specifically recognized by the patient's IgE. Specific nasal challenge test with Asticot extract using a Rhinospir 164 rhinomanometer showed immediate response (1/10 w/v), with a 200% increase in nasal resistances from baseline.

One main allergen of MW 60 kDa was specifically recognized by our patient's IgE. There are no previous reports in the literature that characterize the allergens involved in Asticot hypersensitivity. Asticot maggots should be taken into account as a possible causative agent of respiratory symptoms due to a type I hypersensitivity mechanism in anglers who are exposed to emanations of these live fish baits.