Objective
To investigate the role of helminth-induced IgE in the worm-atopy relationship, the levels of IgE directed against helminthic antigens (Ascaris, Echinococcus, and Schistosoma) and total IgE were determined by radioimmunoassay in the sera of 106 atopic subjects, using extrinsic allergen-specific IgE.
Materials and Methods
A cross-sectional study was conducted in Mosul city, Iraq. Adolescents aged 11-19 years were the target population. The age was classified into three categories:
- Early (11-13 years)
- Middle (14-16 years)
- Late (17-19 years)
The rates of positive attitude among adolescents were presented in a table. The association was tested by chi-square test.
Results
Helminth-specific IgE was detected in ten of the 106 atopic patients. Serum total IgE levels in atopic subjects with helminth-specific IgE (geometric mean, 2101 μg/L) were approximately five-fold higher than those with no helminth-specific IgE (geometric mean, 430 μg/L). The differences were highly significant (P <0.005).
Discussion
IgE holds a unique position among immunoglobulins and is normally present in extremely small amounts. However, generally elevated levels of IgE occur in patients with atopic diseases and individuals infected with helminth parasites. The detection of helminth-specific IgE in 9.4% of our atopic subjects suggests not only that helminth-induced IgE does not protect against atopic reactions but also that individuals can be worm infected and yet produce large quantities of allergen-specific IgE–enough to precipitate clinical atopic reactions.
Conclusion
These results are consistent with findings from other studies, which suggest that IgE production induced by helminths does not always protect against atopic reactions.
Leave a Reply