PROSPECTIVE-STUDY OF LABORATORY-ANIMAL ALLERGY - FACTORS PREDISPOSINGTO SENSITIZATION AND DEVELOPMENT OF ALLERGIC SYMPTOMS

In a prospective study of laboratory technicians, selected indicators of allergy and atopy were studied in an attempt to determine predictor s of laboratory-animal allergy (LAA). Laboratory technicians underwent spirometry, methacholine provocation tests, and blood sampling, and r esponded to a questionnaire during training and after 2 years' work. A mong 38 laboratory-animal-exposed subjects, total IgE before exposure gave the best correlation (P< 0.01; Mann-Whitney U-test) to reported s ymptoms caused by laboratory animals (n = 8) at follow-up. The prevale nce of atopy and allergic symptoms had increased in exposed technician s at follow-up, but this was also found among unexposed matched refere nts (n = 36 pairs). One subject in the exposed group reported asthma b efore exposure, compared with seven at follow-up (P<0.05; Fisher's exa ct test). However, the prevalence of asthma had increased from two to six (not significant) also among unexposed technicians. There were no significant differences between the groups in any measured variable at follow-up. Among 43 subjects who later worked with laboratory animals , 21% had a positive skin prick test for common allergens, as compared with 37% among 112 without animal exposure (P = 0.06; chi(2) test), s uggesting selection for laboratory animal work.