[Correlation of urinary tract infections with the vaginal colonization in postmenopausal women]

Estrogen deficiency is a major contributor to the pathogenesis of urinary tract infections (UTI) in postmenopausal women. After menopause, the vaginal pH increases, lactobacilli disappear from the vaginal flora, and the vagina is predominantly colonized by Enterobacteriaceae, especially Escherichia coli. To better understand the associations between post-menopausal vaginal flora and the development of UTI, we conducted a prospective study among 87 postmenopausal women ages between 50-65 years. Vaginal samples were collected from lateral vaginal wall of women to perform a smear on a glass slide and placed on appropriate media. The smear was then stained with Gram stain. Urine samples were collected and cultured by standard bacteriologic techniques. Vaginal lactobacilli were present in 55.2%, and vaginal Enterobacteriaceae were present in 40.2% of the subjects. Heavy growth of lactobacilli was associated with a lower frequency of vaginal colonization with Enterobacteriaceae members (p<0.001), Streptococcus sp. (p<0.05) and Pseudomonas sp. (p<0.05). The most commonly isolated microorganism was E. coli. The frequency of asymptomatic bacteriuria and symptomatic UTI among postmenopausal women were found 17.5% (15/87) and 11.5% (10/87), respectively. As a result, Enterobacteriaceae colonization of the vagina in postmenopausal women increases the prevalence of asymptomatic bacteriuria and symptomatic UTI (p<0.01 and p<0.05, respectively).