Immunoglobulin E in feces of children with intestinal Ascaris lumbricoides infestation.

Five of 6 fecal extracts from small children with intestinal Ascaris lumbricoides infection were IgE-positive before antiparasitic treatment with mebendazole was given. After treatment one patient still showed high fecal IgE level, but the samples from the remaining children showed either undetectable IgE values, or values just above the limit of detection. The serum IgE concentrations, however, decreased more slowly than the fecal IgE levels did. In the child with persistent high fecal IgE level after therapy, ova from Hymenolepis nana could still be found in feces, although the A. lumbricoides infection had been successfully treated. Gel filtration studies showed that fecal IgE from a patient with the parasitic infection was degraded to fragments corresponding to a molecular weight of approximately 40,000 daltons, similar to that of fecal IgE from a patient with gastrointestinal allergy. The number of IgE-positive fecal extracts in those patients before antiparasitic treatment was given differed significantly from the number of positive fecal IgE extracts from healthy nonallergic children (p less than 0.01), but not from children with different kinds of allergy (p greater than 0.20). The fecal IgA concentrations were not different before and after antiparasitic therapy. The finding of IgE in feces from individuals with intestinal ascaris infection and nearly complete disappearance of IgE in feces after successful therapy is further evidence of local production of IgE in the gut mucosa.