Efficacy of trimethoprim-sulfamethoxazole in treatment of acute diarrhea in a Mexican pediatric population.

The efficacy of trimethoprim-sulfamethoxazole (TMP-SMX) and placebo were compared in a randomized double-blind study of 141 Mexican children with acute diarrhea. Patients who met specific entry criteria received TMP-SMX or an identical appearing placebo for 5 days. Stools were examined for bacterial, viral, and parasitic pathogens. Enterotoxigenic Escherichia coli were the most commonly isolated pathogens (22% of total). Patients given TMP-SMX had a significantly shorter time to "last illness stool" than did those given placebo, but no difference in number of unformed stools in 5 days was found between treatment groups. However, TMP-SMX significantly shortened the illness in patients with fever or many fecal leukocytes. When stool cultures positive for any bacterial pathogen or for enterotoxigenic E. coli were analyzed as separate groups, a significantly faster recovery was observed in patients given TMP-SMX. TMP-SMX is efficacious in the treatment of Mexican children with diarrhea and culture-proved bacterial infection or when the clinical signs and symptoms suggest bacterial enteritis.