Enteroadherent Escherichia coli and diarrhea in children: a prospective case-control study.

The relative contribution of diarrheagenic Escherichia coliwas examined during a 1-year prospective study of hospitalized children in Clermont-Ferrand, France, including 220 case patients (with diarrhea) and 211 matched controls. Fecal isolates were characterized by means of their pattern of adherence to HEp-2 cells and by colony hybridization with DNA probes specific for the six categories of diarrheagenic E. coli. No enteroinvasive or enterotoxigenic E. coli isolates were isolated. Twenty-eight (6.5%) eae-positive isolates and 39 (9%) enteroaggregative E. coliisolatescharacterizedwiththeaggregativeadherenceprobeand/orbytheiradherence pattern were detected; they were equally distributed among the patients and the controls. Diffusely adhering E. coliwasthepredominantpathotype:30.7%weredetectedbytheiradherencepatternand13.7%weredetected with the daaCprobe. They were isolated with similar frequencies from the patients and the controls, thereby showing no association with diarrhea. However, daaC-positive strains were significantly associated with a past record of urinary tract infections. These results suggest that the diffusely adhering E. coliorganisms isolated in the present study are not true intestinal pathogens but may be regarded as resident colonic strains.