[Toxocara and bronchial hyperreactivity--results of a seroprevalence study]

For more than 30 years the ascarid Toxocara canis, a parasite of the dog, has been considered a possible cause of allergic-pulmonal irritations (i.e. asthma bronchial) in man. According to a British study thousands of people are presumably suffering from asthma bronchial as a consequence of Toxocara infestations. The aim of our recent study was the assessment of the Toxocara seroprevalence in patients of varying bronchial reactivity and status of atopy suffering from respiratory disturbances. 191 serum samples from 59 male (mean age: 31.7 years) and 132 female patients (mean age: 36.6 years) with varying atopy status and degree of bronchial reactivity, living in or near Vienna, were examined for specific IgG antibodies against excretory-secretory (E/S) Toxocara canis antigen with enzyme-linked immunosorbent assay (TES-ELISA) and Western blot (TES-WB). In total a Toxocara seroprevalence of 9.4% could be assessed among these patients. 10% of the patients with and 7.8% of the patients without bronchial hyperreactivity were Toxocara-positive. Atopic patients were serologically positive in 7.1% of the cases tested whereas non-atopics showed an antibody prevalence of 14.3%. A comparison of Toxocara seroprevalence assessed within the recent study and in an earlier study among healthy pregnant women in Vienna did not show significant differences. The results of this study carried out in Vienna indicate that patients with bronchial hyper-reactivity or atopy show no higher seroprevalence than the normal population.