Caution: Reptile pets shuttle grasshopper allergy and asthma into homes

Abstract

The numbers of reptiles in homes has at least doubled in the last decade in Europe and the USA. Reptile purchases are increasingly triggered by the attempt to avoid potentially allergenic fur pets like dogs and cats. Consequently, reptiles are today regarded as surrogate pets initiating a closer relationship with the owner than ever previously observed. Reptile pets are mostly fed with insects, especially grasshoppers and/or locusts, which are sources for aggressive airborne allergens, best known from occupational insect breeder allergies. Exposure in homes thus introduces a new form of domestic allergy to grasshoppers and related insects. Accordingly, an 8-year old boy developed severe bronchial hypersensitivity and asthma within 4 months after purchase of a bearded dragon. The reptile was held in the living room and regularly fed with living grasshoppers. In the absence of a serological allergy diagnosis test, an IgE immunoblot on grasshopper extract and prick-to-prick test confirmed specific sensitization to grasshoppers. After 4 years of allergen avoidance, a single respiratory exposure was sufficient to trigger a severe asthma attack again in the patient. Based on literature review and the clinical example we conclude that reptile keeping is associated with introducing potent insect allergens into home environments. Patient interviews during diagnostic procedure should therefore by default include the question about reptile pets in homes.

Keywords: Allergy; Asthma; Grasshopper; IgE; Pets; Reptile; Reptile pets.

Fig. 1

a Nymph of Egyptian locust species Anacridium aegyptium (Fotolia© paulrommer). b Confirmation of specific sensitization by Prick-to-Prick test with Egyptian grasshopper.Crushed wing material of a frozen Egyptian locust (H) and saliva of the boy’s bearded dragon Sony (S) was pricked on the forearm of the patient, in addition to the standard Prick test with inhalant allergens. c Reactivity of patient’s IgE on blotted extracts of migratory grasshopper (Locusta migratoria) legs (a) and wings (b), and from Egyptian locust (Anacridium aegypticum) legs (c) and wings (d). As negative control, a serum of a non-allergic person was tested (0). Bound IgE was detected by peroxidase-labeled anti-IgE antibody and the reaction developed with ECL