Chronic non-specific diarrhea of infancy successfully treated with trimethoprim-sulfamethoxazole.

Fifteen children who fulfilled the criteria of chronic non-specific diarrhea of infancy were evaluated for intestinal bacterial overgrowth. In 10 of 11 successfully investigated children we found bacterial overgrowth of the small intestine by upper respiratory tract microflora. In 9 of 10 children (group I) treated with trimethoprim-sulfamethoxazole the diarrhea ceased immediately, whereas in all children in group II (n = 5; 3 children excluded because of growth of Yersinia enterocolitica) treated with low-lactose diet the diarrhea persisted (p = 0.004). The results indicate that bacterial overgrowth of the small intestine by upper respiratory tract microflora may be a cause of chronic non-specific diarrhea and that this diarrhea may be successfully treated with trimethoprim-sulfamethoxazole.