Transmissible trimethoprim resistance in strains of Escherichia coli isolated from cases of infantile diarrhoea.

Of 190 isolates of Escherichia coli from children aged up to 5 years with diarrhoea, 72 (37.9%) were resistant to trimethoprim and of the 70 isolates tested, 38 transferred high level trimethoprim resistance (MIC greater than 1000 mg/L) into E. coli EC 1005. Of the enterotoxigenic isolates from which trimethoprim resistance was transferred, 41.2% also contained transmissible toxigenic characteristics. All the trimethoprim-resistant isolates were resistant to other antibiotics.