SUMMARY
A conjugative R-plasmid PE004, Inc F11, conferring resistance to ampicillin, tetracycline, streptomycin, kanamycin and trimethoprim was obtained from an E. coli serotype 026 isolate from the stool of a child with acute diarrhoea. The R-plasmid PE004 also co-transfers an enteropathogenicity antigen without the production of enterotoxins or manifestation of invasiveness. It is not yet known whether this transferable antigen mediates enterocyte damage with consequent diarrhoea. The R-plasmid was of molecular weight 2·4 megadaltons (3·7 kilobase) with a transfer frequency of 6 × 10-4 cfu/ml E. coli J53-1.
The uncontrolled medication with antibiotics in cases of acute diarrhoea could select gut bacteria not only possessing R-plasmids conferring resistance to several antibiotics but with associated undesirable extrachromosomal genes.