Antimicrobial resistance of enteropathogenic Escherichia coli strains from a nosocomial outbreak in Kenya

Abstract

The majority of the 78 enteropathogenic (EPEC) and the 151 non-EPEC Escherichia coli strains isolated from preterm neonates during an outbreak of gastroenteritis in a hospital in Nairobi, Kenya, were resistant to trimethoprim-sulfamethoxaxole, chloramphenicol, oxytetracycline and ampicillin, but only a few strains were resistant to cefazolin, cefamandole, cefotaxime, amikacin and nalidixic acid. Fourteen different antimicrobial resistance patterns were observed in the 229 strains of E. coli analysed. Eighty-two percent of the EPEC strains belonged to two resistance patterns compared with 79% of non-EPEC strains which exhibited three resistance patterns. There was no consistent relationship between plasmid profile group and antimicrobial resistance pattern, although one resistance pattern was more frequently observed in EAF-positive strains belonging to the dominant plasmid profile group. Nine percent of the EPEC strains were resistant to gentamicin compared to 37% in the non-EPEC group. No correlation was observed between administration of gentamicin and percentage of resistant strains isolated. None of the nine neonates receiving gentamicin died during the outbreak. Gentamicin resistance was observed in E. coli strains from six out of these nine neonates. Five out of fourteen neonates who received other antimicrobials, or no antibiotic treatment at all, died.