Association between Escherichia coli bacteriuria and renal function in women: long-term follow-up.

BACKGROUND

We sought to investigate whether Escherichia coli bacteriuria is associated with a decline in renal function or with the development of end-stage renal failure after long-term follow-up.

METHODS

We performed a full cohort analysis for women who participated in 2 population-based studies. The baseline cohort consisted of women who collected morning midstream urine samples that were stored. In the cohort study, the presence of E coli bacteriuria was subsequently determined by real-time polymerase chain reaction. After a mean +/- SD follow-up of 11.5 +/- 1.7 years, blood samples were drawn from 490 women. In the nested case-control study, cases comprised all women who underwent kidney therapy (hemodialysis or renal transplantation) between participation in the baseline cohort study and a mean +/- SD of 13.8 +/- 7.4 years later.

RESULTS

The mean +/- SD age at baseline was 45.0 +/- 3.2 years, and 48 women (10%) had E coli bacteriuria. After 11.5 years, the mean +/- SD creatinine clearance (Cockroft-Gault formula) was similar between the 2 groups (87 +/- 21 mL/min [1.5 +/- 0.4 mL/s] and 85 +/- 18 mL/min [1.4 +/- 0.3 mL/s] for women who had and those who did not have bacteriuria, respectively). In the nested case-control study, the prevalence of E coli bacteriuria was 14% among cases and control subjects. The odds ratio corrected for age for the development of end-stage renal failure in the presence of E coli bacteriuria at baseline was 1.1 (95% confidence interval, 0.4-2.8; P = .86).

CONCLUSION

Escherichia coli bacteriuria is not associated with a decline in renal function or with the development of end-stage renal failure in a population of generally healthy women during 12 to 14 years of follow-up.