HEp-2-adherent Escherichia coli strains associated with acute infantile diarrhea, São Paulo, Brazil.
In this paired case-control study of infants with diarrhea in São Paulo, we examined the association between HEp-2-adherent Escherichia coli strains and diarrhea. We tested isolates from stool specimens of infants with diarrhea and matched controls in an HEp-2 cell adherence assay; we then hybridized isolates with DNA probes and identified enteropathogenic E. coli (EPEC), enteroaggregative E. coli (EAEC), and diffusely adherent E. coli (DAEC). From 100 patient-control pairs, we isolated 78 HEp-2-adherent strains; of these, 61 strains were single pathogens identified in stools of infants with diarrhea. While typical EPEC was significantly associated with diarrhea (p<0.001), EAEC was more frequently associated with diarrhea in clinical cases (20%) compared with healthy controls (3%) (p<0.001). Atypical EPEC, showing a localized adherence-like pattern, was also more common in patients than controls (p>0.1). DAEC was isolated with equal frequency from patients and controls (p>0.1).
Universidade Federal de São Paulo, Escola Paulista de Medicina, São Paulo, Brazil. scaletsky@ecb.epm.br
Isabel C A
IC
Scaletsky
Sandra H
SH
Fabbricotti
Sueli O C
SO
Silva
Mauro B
MB
Morais
Ulysses
U
Fagundes-Neto
D001422:Bacterial Adhesion; D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D002460:Cell Line; D003968:Diarrhea, Infantile / Q000453:epidemiology / Q000382:microbiology*; D004926:Escherichia coli / Q000145:classification / Q000302:isolation & purification* / Q000472:pathogenicity*; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male