ABSTRACT
Enteropathogenic Escherichia coli (EPEC) often exhibits localized adherence or diffuse adherence to HEp-2 cells. We recently provided evidence that HEp-2 cell-adherent or enteroadherent E. coli (EAEC) not belonging to EPEC serogroups was the cause of diarrhea among U.S. travelers to Mexico. In the present study, we looked for EAEC and EPEC in stool specimens from 154 children with acute diarrhea and 137 well children seen at several outpatient clinics in Guadalajara, Mexico. EAEC showing localized adherence (EAEC-L) was isolated from 13.0% of the patients and 0.7% of the controls (P less than 0.0001). EAEC showing diffuse adherence (EAEC-D) was recovered from 20.8% of the patients and 7.3% of the controls (P less than 0.001). EPEC was isolated from 4.5 and 6.7% of the patients and controls, respectively. Among all enteropathogens, only enterotoxigenic E. coli occurred as commonly (21.4%) as EAEC-D and EAEC-L did in children with diarrhea. Of the EAEC-L strains isolated from children with diarrhea, 20% belonged to recognized EPEC serogroups, and 3.1% of EAEC-D strains belonged to recognized EPEC serogroups. This study suggests that EAEC may be an important pediatric enteropathogen in Mexican children with diarrhea and further supports the observation that adherence to HEp-2 cells may be a marker of virulence independent of EPEC serogroup among E. coli strains.
Subject(s)
Bacterial Adhesion , Diarrhea/microbiology , Escherichia coli Infections/microbiology , Escherichia coli/pathogenicity , Cell Line , Child , Child, Preschool , Diarrhea/epidemiology , Diarrhea, Infantile/epidemiology , Diarrhea, Infantile/microbiology , Escherichia coli Infections/epidemiology , Humans , Infant , Mexico , VirulenceABSTRACT
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.
