, stool specimens of children less than 2 years of age with diarrhoea (n5218) and without diarrhoea (n586), living in Vitó ria, Espírito Santo, Brazil, were examined for the presence of diarrhoeagenic Escherichia coli. E. coli isolates were tested by colony blot hybridization with specific DNA probes designed to detect EPEC, ETEC, EIEC, EAEC, DAEC and EHEC/STEC. Diarrhoeagenic E. coli strains were detected as the sole pathogen in stools of 92 (30.3 %) children, including 72 (33.0 %) with diarrhoea and 20 (23.2 %) without diarrhoea. DAEC was the most frequent pathotype and was found significantly more often from patients (18.3 %) than from controls (8.1 %) (P,0.05), particularly among children more than 1 year of age (P50.01). Atypical EPEC and EAEC isolates were isolated from both patients (5.5 % and 4.6 %, respectively) and controls (6.9 % and 6.9 %, respectively). ETEC was more frequently isolated from patients (3.2 %) than controls (1.2 %). Typical EPEC (0.9 %) and EIEC (0.4 %) isolates were detected only in children with diarrhoea. In conclusion, our data suggest that DAEC should be considered potential pathogens in the region of Brazil studied. INTRODUCTIONDiarrhoeagenic Escherichia coli constitute an important group of pathogens associated with enteric diseases. Six E. coli pathotypes associated with diarrhoea are currently recognized: enteropathogenic E. coli (EPEC), enterotoxigenic E. coli (ETEC), enteroinvasive E. coli (EIEC), enterohaemorrhagic E. coli (EHEC) or Shiga toxin-producing E. coli (STEC), enteroaggregative E. coli (EAEC), and diffusely adherent E. coli (DAEC). EPEC are divided into typical (tEPEC) and atypical (aEPEC) subgroups depending on the presence or absence of the EPEC adherence factor (EAF) plasmid, respectively (Nataro & Kaper, 1998).Each type of diarrhoeagenic E. coli is defined on the basis of distinct virulence characteristics, and DNA probes for these characteristics have been developed to distinguish types of diarrhoeagenic E. coli from each other and from nonpathogenic E. coli strains of normal flora (Nataro & Kaper, 1998).It has become clear that there are regional differences in the relative prevalence of the different types of diarrhoeagenic E. coli and such differences may affect the overall regional prevalence of diarrhoeal diseases. In Brazil, several studies have investigated the relative prevalence of diarrhoeagenic E. coli among children with and without diarrhoea. However, most of these studies have been performed predominantly in the cities of São Paulo and Rio de Janeiro, two large urban centres in south-eastern Brazil (Rosa et al., 1998;Gomes et al., 1991;Scaletsky et al., 1999Scaletsky et al., , 2002bRegua-Mangia et al., 2004;Araujo et al., 2007). The aim of the present study was to determine the relative prevalence and the role of the different E. coli pathotypes as cause of acute diarrhoea in the city of Vitó ria, Espírito Santo, another large urban centre in south-eastern Brazil, where childhood diarrhoea is endemic.Abbreviations: DAEC, diffusely adherent E. c...