Virulence characteristics and DNA fingerprints of Escherichia coli isolated from women with acute uncomplicated pyelonephritis.

PURPOSE

Previous studies indicated that acute pyelonephritis in infants is initiated by the dominance of uropathogenic strains in fecal flora. Such pathogenic evidence, however, is still lacking for adult women. In this study, the validity of a fecal-perineal-urethral hypothesis in acute uncomplicated pyelonephritis of adult women was assessed at a genetic level.

MATERIALS AND METHODS

A total of 1,200 Escherichia coli isolates from the urine and rectal swab of 12 adult women with acute uncomplicated pyelonephritis were examined. The clonality of the urinary and fecal isolates was evaluated by genotyping of 6 urovirulence determinants and pulsed-field gel electrophoresis. Furthermore, urovirulence genotypes were examined in E. coli isolates from the rectal swab of 30 normal healthy women (mean 26.7 isolates per person).

RESULTS

The E. coli strains causing pyelonephritis were present in the rectal swab in 10 of 12 patients and were a predominant fecal clone in 9 cases. Also, P-fimbriated strains dominated in the fecal flora in 10 of 30 normal healthy women.

CONCLUSIONS

The clonal identity of the urinary and fecal strains in acute pyelonephritis clearly supports the fecal-perineal-urethral hypothesis.