RUTI refers to more than two infections in six months or more than three infections in one year. Most recurrences are thought to represent reinfection rather than relapse, although occasionally a persistent focus can produce relapsing infection. It’s useful to try to distinguish clinically between relapse and reinfection, because relapsing infection warrants more extensive urologic evaluation, longer therapy, and, in some cases, surgery.
Who gets recurrent UTIs and how common is it?
Recurrent UTIs are common among young, healthy women with anatomically and physiologically normal urinary tracts. In a recent study of college women with their first UTI, 27% experienced at least one recurrence within the six months following the initial infection and 2.7% had a second recurrence during this same time period. When the first infection is caused by Escherichia coli, women appear to be more likely to develop a second UTI within six months than those with a first UTI due to another organism.
What’s interesting is that established evidence suggests that changes of the normal vaginal bacteria, especially the loss of lactobacilli, may predispose women to colonization with E. coli and to UTI. This is the reason most physicians would recommend women not to douche, and to not to overuse perfumed soaps.
Reinfection vs. Relapse:
For most physicians it’s often very difficult to distinguish between a relapse and reinfection. A recurrent UTI is classified as a reinfection if the recurrence is caused by a different strain of bacteria than the one responsible for the original infection. In clinical practice, a recurrent UTI is defined as a relapse if the infecting strain is the same and the recurrence occurs within two weeks of the completion of treatment for the original infection. Moreover, long-term studies have shown that E. coli strains are capable of causing recurrent UTI one to three years later, despite appropriate treatment and disappearance of the organism in repeated urine cultures.
- Biologic or genetic factors: Women with recurrent UTI have been shown to have an increased susceptibility to vaginal colonization with bacteria compared with women without a history of recurrences.
- Postmenopausal women: In postmenopausal women factors that affect bladder emptying contribute to chronic/recurrent UTIs, with the main risk factors in those women being urinary incontinence, and the presence of a cystocele (bladder prolapse).
- Behavioral risk factors: Sexual intercourse, spermicide use, and a history of recurrent UTI are strong risk factors for UTI. Even spermicide-coated condom use results in an increased risk of UTI. Recent antibiotic use, which adversely affects vaginal flora, also is strongly associated with an increased risk of UTI.
- The strongest risk factor is the frequency of sexual intercourse; Other risk factors include: having a new sex partner during the past year, having a first UTI at or before 15 years of age and having a mother with a history of UTIs
- Pelvic anatomy: Pelvic anatomy may predispose to recurrent UTI in some women, especially those who do not have other risk factors for UTI. As an example of this, the distance from the urethra to anus was significantly shorter in patients with recurrent UTIs in some studies
- Contraception: Women with recurrent UTIs who are sexually active or who use spermicides (particularly when used with diaphragms), should be counseled about the possible association between their infections and the use of spermicides.
- Voiding after intercourse and drinking lots of water: Voiding right after intercourse and more liberal fluid intake may reduce the risk of recurrent
- Cranberry juice: Cranberry juice has been touted as an effective home remedy for preventing UTI. How does it work? Well, studies have shown that cranberry juice inhibits adherence of bacteria to uroepithelial cells.
- Taking antibiotics to prevent recurrent UTI: Antibiotic prophylaxis has been shown to be effective in reducing the risk of recurrent UTI in women. Individualized decisions to be made with your doctor are whether you should use continuous antibiotics, or just antibiotics after intercourse– both of which have been supported as effective for prevention.