Enteropathogenic and enteroadherent-aggregative Escherichia coli in children with persistent diarrhoea and...

Our investigation of 61 children with persistent diarrhoea and malnutrition (PDM) aimed to characterize in them the range of enteropathogenic E. coli. Age- and sex-matched control groups consisted of 42 healthy children and 16 children with marasmus but without diarrhoea. E. coli isolates from stool cultures were serotyped, examined for Vero cells cytotoxicity, tested for enterotoxin production (LT, ST, VTI, and VTII). Synthetic oligonucleotide probes were used to test for enteroinvasivity, EPEC adherence factor, and for EAggEC. Classical E. coli serotypes commonly associated with diarrhoea (O18, O26, O119, O126) were isolated from six of 60 (10%) children with PDM. Serotype O126 was isolated from two of 42 (4.8%) healthy children and serotype O119 from one of 16 (6%) marasmic controls. Testing for Vero toxin production was negative in all isolates. Classical ETEC were confirmed in four of 60 (ST 2; LT 2) cases of PDM; no ETEC were recovered from 58 control patients. EAggEC were identified in five children with PDM and in five healthy controls without diarrhoea or malnutrition. This controlled study has shown that, in The Gambia, E. coli carrying known virulence factors are prevalent but, with the exception of enterotoxigenic E. coli, the various forms of pathogenic E. coli do not seem to be important pathogens in children with persistent diarrhoea.