Although acute urinary tract infections are common in young women, the associated risk factors have not been defined prospectively.

Background. Urinary tract infections (UTIs) are common among women and frequently recur. Depletion of vaginal lactobacilli is associated with UTI risk, which suggests that repletion may be beneficial. We conducted a double-blind placebo-controlled trial of a Lactobacillus crispatus intravaginal suppository probiotic (Lactin-V; Osel) for prevention of recurrent UTI in premenopausal women. Methods. One hundred young women with a history of recurrent UTI received antimicrobials for acute UTI and then were randomized to receive either Lactin-V or placebo daily for 5 days, then once weekly for 10 weeks. Participants were followed up at 1 week and 10 weeks after intervention and for UTIs; urine samples for culture and vaginal swabs for real-time quantitative 16S ribosomal RNA gene polymerase chain reaction for L. crispatus were collected. Results. Recurrent UTI occurred in 7/48 15% of women receiving Lactin-V compared with 13/48 27% of women receiving placebo (relative risk [RR], .5; 95% confidence interval, .2–1.2). High-level vaginal colonization with L. crispatus (≥10⁶ 16S RNA gene copies per swab) throughout follow-up was associated with a significant reduction in recurrent UTI only for Lactin-V (RR for Lactin-V, .07; RR for placebo, 1.1; P < .01). Conclusions. Lactin-V after treatment for cystitis is associated with a reduction in recurrent UTI. Larger efficacy trials of this novel preventive method for recurrent UTI are warranted. Clinical Trials Registration. NCT00305227.

To define host factors associated with an increased risk of recurrent urinary tract infection (RUTI), a case-control study was conducted in 2 populat

Bacterial siderophores are known to bind various metals in vitro but are generally thought of as iron chelators in vivo. MS now demonstrates that yersiniabactin binds copper in vivo, with yersiniabactin expression correlated to bacterial fitness. Bacterial pathogens secrete chemically diverse iron chelators called siderophores, which may exert additional distinctive functions in vivo. Among these, uropathogenic Escherichia coli often coexpress the virulence-associated siderophore yersiniabactin (Ybt) with catecholate siderophores. Here we used a new MS screening approach to reveal that Ybt is also a physiologically favorable Cu(II) ligand. Direct MS detection of the resulting Cu(II)–Ybt complex in mice and humans with E. coli urinary tract infections demonstrates copper binding to be a physiologically relevant in vivo interaction during infection. Ybt expression corresponded to higher copper resistance among human urinary tract isolates, suggesting a protective role for this interaction. Chemical and genetic characterization showed that Ybt helps bacteria resist copper toxicity by sequestering host-derived Cu(II) and preventing its catechol-mediated reduction to Cu(I). Together, these studies reveal a new virulence-associated function for Ybt that is distinct from iron binding.

The objective of this study was to examine genital tissue, vaginal fluid, and vaginal microbial flora at 3 phases of the menstrual cycle in asymptom

Extraintestinal Escherichia coli (ExPEC), a heterogeneous group of pathogens, encompasses avian, neonatal meningitis, and uropathogenic E. coli strains. While several virulence factors are associated with ExPEC, there is no core set of virulence factors that can be used to definitively differentiate these pathotypes. Here we describe a multiplex of four virulence factor-encoding genes, yfcV , vat , fyuA , and chuA , highly associated with uropathogenic E. coli strains that can distinguish three groups of E. coli : diarrheagenic and animal-associated E. coli strains, human commensal and avian pathogenic E. coli strains, and uropathogenic and neonatal meningitis E. coli strains. Furthermore, human intestinal isolates that encode all four predictor genes express them during exponential growth in human urine and colonize the bladder in the mouse model of ascending urinary tract infection in higher numbers than human commensal strains that do not encode the four predictor genes ( P = 0.02), suggesting that the presence of the predictors correlates with uropathogenic potential.