Distribution of O groups Among Escherichia coli Strains Isolated from Urinary Tract Infections, and Their Drug Reristance

Abstract

The present paper describes the frequency distribution of serological groups of Escherichia coli isolated from specimens of urines from patients (mostly cystitis) in the Shinshu University Hospital (Matsumoto City, Japan) during a period between December 1964 and March 1966.
One hundred and twenty three strains of E. coli isolated from 123 patients were identified by the biochemical examinations, then were submitted for serological grouping. The serological typing was carried out with O1 to O146, and H1 to H48 antisera.
Eighty-six strains out of 123 (70%) were serologically classified; 26 strains (21%) were smooth but were not agglutinated by any antisera of O groups used, and 10 strains (8%), were rough. Among twenty different serogroups which were identified, serogroups O2, O4, O6, O23 and O75 were encountered more frequently than others. These five common groups accounted for 68% of the typable strains.
These results are well agreed with the reports of others in Europe, U.S.A., Canada etc. in which serogroups O1, O2, O4, O6, O23, and O75 are prevalent, usually accounted for about 60 per cent of the typable strains, among E. coli isolated from the urinary tract infections.
Approximately 60 per cent of E. coli strains described here were resistant to a number of common antibiotics such as chloramphenicol, tetracyclines, streptomycin, and sulfonamides. It was demonstrated that the drug resistance was due maily to the possession of the so called “multiple drug-rsesistant transfer factor” which is known being transmissible from cell to cell by conjugation.