Both the American Urological Association and the Infectious Disease Society of America recommend that fluoroquinolones be avoided, if possible, in the treatment of uncomplicated UTIs.5 A better therapeutic choice would be nitrofurantoin or trimethoprim-sulfamethoxazole.
WHAT THIS EVIDENCE MEANS FOR PRACTICE
Postcoital antibiotic prophylaxis is an effective strategy for the prevention of UTIs associated with sexual intercourse in premenopausal women. Although the optimal duration of such a regimen was not addressed in this study, it would be appropriate to revisit the need for prophylaxis after 1 year.
Dieter AA, Amundsen CL, Visco AG, Siddiqui NY. Treatment for urinary tract infection after midurethral sling: a retrospective study comparing patients who receive short-term postoperative catheterization and patients who pass a void trial on the day of surgery. Female Pelvic Med Reconstr Surg. 2012;18(3):175–178.
Urinary tract catheterization and urogynecologic surgery are associated with an increased risk for UTI. The risk of UTI following a midurethral sling procedure, in particular, ranges from 4.1% to 33.6% in the literature.6,7 To further explore the risk of UTI after placement of a midurethral sling, Dieter and colleagues followed 138 women who had undergone the procedure with and without concomitant pelvic surgery. The primary outcome was treatment of UTI within the first 3 weeks postoperatively.
Catheterization increased the risk of UTI
Fifty-eight percent of women required placement of a catheter postoperatively—either an indwelling Foley or intermittent self-catheterization. The duration of catheterization ranged from 1 to 14 days, with a mean of 4 days. The incidence of UTI was significantly higher in the group that was catheterized postoperatively, compared with the group that was not (30.0% vs 5.2%), and catheterization remained an independent risk factor for UTI after adjusting for other confounding factors.
Data may not be applicable to other types of surgery
This large retrospective cohort study of a well-characterized population was based on consistent postoperative data related to catheterization and UTI treatment. Because the study focused on patients who had undergone placement of a midurethral sling, its findings may not be applicable to women undergoing other types of pelvic surgery, including general gynecologic procedures. However, given the significant difference in the rate of UTI between the two groups, the increased risk of UTI may be at least partially attributable to short-term postoperative catheterization rather than urinary tract instrumentation during the procedure.
WHAT THIS EVIDENCE MEANS FOR PRACTICE
The risk of UTI is increased with short-term catheterization following placement of a midurethral sling. There may be a role for antibiotic prophylaxis in the setting of short-term postoperative catheterization; however, a prospective, randomized, placebo-controlled study is needed to determine whether the rate of UTI would be reduced.
Vaginal estrogen prevents recurrent UTIs among postmenopausal women
Raz R, Stamm WE. A controlled trial of intravaginal estriol in postmenopausal women with recurrent urinary tract infections. N Engl J Med. 1993;329(11):753–756.
The tissues of the vagina, urethra, bladder, and pelvic floor musculature all express estrogen receptors.8 In postmenopausal women, the effects of decreased estrogen on the urinary tract include a rise in the vaginal pH level and decreased colonization with Lactobacillus. These effects predispose this population to an increased risk for UTI.3 The literature does not support the use of oral estrogen replacement as a therapy for recurrent UTI; however, data suggest that vaginal estrogen replacement may be helpful.9
Raz and Stamm conducted their randomized trial of 93 postmenopausal women with a history of recurrent UTIs to elucidate the effects of vaginal estrogen on the risk of UTI. Fifty women were randomly assigned to treatment with intravaginal estriol cream (0.5 mg nightly for 2 weeks, followed by 0.5 mg twice weekly for 8 months), and 43 women were randomly assigned to placebo (equivalent regimen). Compared with the placebo group, the women treated with estriol experienced a significantly reduced risk of UTI (0.5 vs 5.9 infections per patient-year), increased lactobacilli on vaginal cultures (61% vs 0%), decreased vaginal pH, and a lower rate of colonization with Enterobacteriaceae species.
Although this rigorous double-blind, randomized, placebo-controlled trial was published 20 years ago, its findings remain significant—and have been corroborated in other studies.9
Pros and cons of vaginal estrogen replacement
Raz and Stamm utilized vaginal estriol; the preparations used most commonly today are conjugated estrogens (Premarin) and estradiol (Estrace). Vaginal estrogen formulations can be expensive. Compliance also can wane over time. This study, in particular, showed a discontinuation rate of 28%; mild local reactions were the reason. Although the women who discontinued treatment in this study were included in the final analysis, no subanalysis of these patients was published.