Predictive value of Escherichia coli susceptibility in strains causing asymptomatic bacteriuria for women with recurrent symptomatic urinary tract infections receiving prophylaxis.

A significant proportion of women develop a recurrence following an initial urinary tract infection (UTI). In women with recurrent UTI, the predictive value of asymptomatic bacteriuria (ASB) for the development of a subsequent UTI has not yet been established and it is not known whether information from an asymptomatic sample is useful in guiding antimicrobial therapy. To address these questions, we used data that originated from the 'Non-antibiotic prophylaxis for recurrent urinary tract infections' (NAPRUTI) study: two randomized controlled trials on the prevention of recurrent UTI in non-hospitalized premenopausal and postmenopausal women (n=445). During 15months of follow-up, no difference was observed in the time to a subsequent UTI between women with and without ASB at baseline (hazard ratio: 1.07, 95% CI 0.80-1.42). The antimicrobial susceptibility and pulsed-field gel-electrophoresis (PFGE) pattern of 50 Escherichia coli strains causing a UTI were compared with those of the ASB strain isolated 1month previously. The predictive values of the susceptibility pattern of the ASB strain, based on resistance prevalence at baseline, were ≥76%, except in the case of nitrofurantoin- and amoxicillin-clavulanic acid-resistance. Asymptomatic and symptomatic isolates had similar PFGE patterns in 70% (35/50) of the patients. In the present study among women with recurrent UTI receiving prophylaxis, ASB was not predictive for the development of a UTI. However, the susceptibility pattern of E. coli strains isolated in the month before a symptomatic E. coli UTI can be used to make informed choices for empirical antibiotic treatment in this patient population.

Antibiotic susceptibility of unselected uropathogenic Escherichia coli from female Dutch general practice patients: a comparison of two surveys with a 5 year interval.

OBJECTIVES: To optimize empirical treatment of urinary tract infections (UTIs), regular evaluation of the antibiotic susceptibility of the most common uropathogen, Escherichia coli, is necessary. We compared the antibiotic prescription rate for UTIs in women and the E. coli antibiotic susceptibility results, including the prevalence of extended-spectrum ß-lactamase (ESBL)-producing strains, in 2009 with data collected 5 years earlier. PATIENTS AND METHODS: Urinary samples from female patients with symptoms of uncomplicated UTI in 42 general practices were collected over a 6 month period. Uropathogens were identified and the antibiotic susceptibility of E. coli was determined. RESULTS: We analysed 970 urine cultures, of which 785 (81%) were considered positive (≥ 10(3) cfu/mL). E. coli accounted for 72% of the isolates. ESBLs showed an increase between the two surveys (0.1% versus 1%; P < 0.001), while no difference in antibiotic susceptibility to the commonly used antimicrobial agents for UTIs was observed. A significantly lower susceptibility rate to co-amoxiclav was observed in the eastern region of the Netherlands, as compared with the northern region (80% versus 92%; P <  0.05). Consistent with national guidelines, the prescription rate of trimethoprim decreased over time (19% versus 5%; P  < 0.05) whereas nitrofurantoin and fosfomycin rates showed an increase (58% versus 66% and 0% versus 6% respectively, both P  < 0.05). CONCLUSIONS: Over a 5 year period, the antibiotic susceptibility of uropathogenic E. coli did not change in female patients with uncomplicated UTI in the Netherlands, but ESBL prevalence increased. With respect to the prescription of antimicrobial agents, compliance with national UTI guidelines was good.