In acute pyelonephritis, bacterial resistance to co-trimoxazole predicts treatment failure, but the clonal basis of such resistance is undefined. We did molecular and serological analyses of 170 Escherichia coli urine isolates obtained in 1994-96 from women with acute pyelonephritis. 12 (7%) of the pyelonephritis isolates were in clonal group A (CGA; responsible for 38-51% of co-trimoxazole resistance in acute cystitis), including ten (34%) of 29 isolates that were resistant to co-trimoxazole. CGA isolates were obtained from diverse locations across the USA and were related to the O15:K52:H1 clone of the 1986-87 outbreak in London, UK. Thus, CGA is broadly disseminated and contributes to co-trimoxazole resistance in pyelonephritis as well as in cystitis.
Bibliographical noteFunding Information:
This paper is based on work supported by Office of Research and Development, Medical Research Service, Department of Veterans Affairs; National Institutes of Health grant DK-47504; National Research Initiative Competitive Grants Program/US Department of Agriculture grant 00-35212-9408; Bayer; Wyeth-Ayerst; and Alameda County District Attorney General's Fund. The sponsors of the study had no role in study design, data collection, data analysis, data interpretation, or writing of the report.