Clinical and laboratory predictors of bacterial diarrhea in a tropical environment.

A total of 180 patients with diarrhea, 6 years and below, were seen and evaluated in our pediatric clinic during the months of July to December, 1986. A bacterial pathogen was isolated from the stools in 24/180 (13%). The best historical factors for predictive accuracies were abrupt onset, no vomiting before the onset of diarrhea, and greater than four stools per 24 hours. The presence of fecal leukocytes was the best screening tool for stool culture positivity. The patients identified with the above three historical factors and positive for fecal leukocytes had an 83% probability of having a positive bacterial stool culture compared to only a 5% probability if any one of the factors was absent. We were able to identify a subpopulation of American dependents in a tropical environment with diarrhea who had a high probability of having a bacterial stool pathogen based on historical factors and the fecal leukocyte test.