Recurrent UTIs in Women: How to Refine Your Care
Which risk factors are (really) associated with recurrence? Which prophylactic and nonpharmacologic strategies are useful? This guide provides the answers.
PREVENTION DOS AND DON’TS
Popular myth suggests that recurrent UTIs are more common in patients who do not void after intercourse or those who douche, consume caffeinated beverages, or wear noncotton underwear. Research, however, has failed to show a relationship between any of these factors and recurrent UTIs.13,18 Clinicians should therefore stop recommending that patients modify these behaviors to decrease recurrent infections.
Antibiotic prophylaxis decreases the rate of recurrent UTI by 95%.29 It has been recommended for women who have had two or more UTIs in the past six months or three or more UTIs in the past year. 29,30 Effective strategies to prevent recurrent UTI are low-dose continuous antibiotic prophylaxis or postcoital antibiotic prophylaxis.
While a test-of-cure culture is not typically recommended following treatment for uncomplicated UTI, you will want to obtain a confirmatory urine culture one to two weeks before starting low-dose antibiotic prophylaxis. Base your choice of antibiotic on known patient allergies and previous culture results. Agents typically used are trimethoprim, TMP-SMX, or nitrofurantoin (see Table 4), none of which demonstrated superiority in a Cochrane review.31-33 Although the same review showed no optimal duration of treatment, six to 24 months of treatment is usually recommended.29,33
A single dose of antibiotic following intercourse may be as effective as daily low-dose prophylaxis for women whose UTIs are related to sexual activity.34 Studies have shown that single doses of TMP-SMX, nitrofurantoin, cephalexin, or a fluoroquinolone (see earlier notes about the FDA warning on fluoroquinolone use) are similarly effective in decreasing the rate of recurrence (see Table 4).31,35,36
Several nonpharmacologic strategies have been suggested for prevention of recurrent UTI. Among them are use of cranberry products, lactobacillus, vaginal estrogen in postmenopausal women, methenamine salts, and
A 2012 Cochrane review of 24 studies found that cranberry products were less effective in preventing recurrent UTIs than previously thought, with no statistically significant difference between women who took them and those who did not.37
Results have been mixed in using lactobacilli or probiotics to prevent recurrent UTIs. One study examining the use of lactobacilli to colonize the vaginal flora found a reduction in the number of recurrent infections in premenopausal women taking intravaginal lactobacillus over 12 months.38 A second study, involving postmenopausal women, found that those who were randomized to take lactobacillus tablets for 12 months had more frequent recurrences of UTIs than women randomized to take daily TMP-SMX.39 However, this last study was designed as a noninferiority trial, and its results do not negate the prior study’s findings. Additionally, vaginal estrogen, which is thought to work through colonization of the vagina with lactobacilli, has prevented recurrent UTIs in postmenopausal women.40
Ascorbic acid (which is bacteriostatic), methenamine salts (which are hydrolyzed to bactericidal ammonia and formaldehyde), and
As noted, the only behavioral modifications that have been shown to decrease the risk for recurrent UTI are discontinuing the use of spermicides/spermicide-coated condoms or oral contraceptives, and decreasing the frequency of intercourse.13
Joan is started on a three-day course of TMP-SMX. Further questioning reveals that each of her three UTIs followed sexual intercourse. Her clinician discusses the options of self-directed therapy using continuous prophylaxis or postcoital prophylaxis, either of which would be an appropriate evidence-based intervention for her. After engaging in shared decision-making, she is prescribed TMP-SMX to be taken as a single dose following intercourse in the future.
