This series of posts explores the treatment and prevention of urinary tract infections in women. We continue today with a discussion of frequent or recurrent UTI and how to evaluate and prevent them.
Urinary Tract Infections (UTI) understandably can cause considerable discomfort and inconvenience. These infections may result in inconvenient trips to a health provider, lead to absence from work, and overall have a negative impact on quality of life. Many people, unfortunately, know that a single UTI can turn into a vicious circle where infections follow each other, one after another. I frequently see women and men suffering from this miserable cycle. Determining the underlying cause and how to best treat this is often relatively simple.
A discussion of recurrent urinary tract infections (rUTI) begins with understanding that, generally, UTI are defined by the presence of disease-causing bacteria in the urine along with urinary symptoms (such as burning, urinary frequency, incontinence, etc.). When those symptomatic infections become too frequent, we call theme recurrent. We usually consider 2 separate UTI in 6 months or 3 UTI in one year to be recurrent. I say “separate” because developing an infection, being treated initially with an ineffective antibiotic (often due to bacterial resistance), followed by a second antibiotic, would be considered one UTI. I also want to stress that just because infections are less than 3 times per year does not make them “normal” or that they should not be evaluated. Rather, infections that are more frequent may require a closer evaluation.
Another area of confusion surrounds “complicated” urinary tract infections versus recurrent infections. Complicated infections are associated with abnormal factors such as a urinary dysfunction or multiple drug resistance of bacteria. Common urinary tract dysfunctions would include being unable to empty the bladder (urinary retention), a bladder stone, or a pocket/pouch off of the bladder or urethra (diverticulum). Most patients with recurrent UTI do not have one of these complicating factors and so do not have a complicated UTI. This is important because longer courses of antibiotics should be prescribed for complicated UTI but should not be used for uncomplicated, recurrent UTI.
One of the greatest concerns that I hear from patients is the high number of antibiotics they end up receiving for their recurrent UTI. These multiple courses of antibiotics can have profound effects on the normal bacteria that populate the intestines, vagina, bladder and skin. A serious infection of the colon called C. difficile colitis can result and is more common with some types of antibiotics. But even without this serious infection, the repeated use of antibiotics to treat recurrent UTI is associated with more frequent urinary infections, including infections involving the kidney. Antibiotic use in recurrent UTI can also be more problematic as there seems to be a tendency for patients to be prescribed longer courses of antibiotics for recurrent infections, even when this provides no added benefit.
I begin the evaluation of a patient referred for recurrent UTI by first trying to determine if they are having symptoms from infections. This sounds simplistic but it might be surprising to learn the number of patients who either do not have a history of symptoms (so very unlikely to have UTI) or have symptoms without evidence of bacteria. Those with urinary symptoms without bacteria should have an investigation of an alternate cause.
Invasive testing such as looking into the bladder with a scope (cystoscopy) or radiology tests including ultrasound or CT are not routinely ordered on all patients with recurrent UTI. However, those patients who have a history to suggest an abnormality of the kidney or bladder such as a prior pelvic surgery, prior kidney or bladder stones, or pelvic radiation may benefit from a more detailed evaluation. But it is important to remember that most patients with recurrent infections will not have a complicating factor that would show up on an ultrasound or scope looking in the bladder.
If an underlying abnormality is not identified, there are numerous strategies to reduce the frequency of recurrent UTI. Many of these focus on attempting to restore the normal bacteria inhabiting the bladder and vagina, by reducing the need for further antibiotics.
Cranberry prophylaxis has shown mixed results with cranberry juice probably providing some benefits but limited by a taste most people find objectionable. Cranberry extracts have widely varying levels of the proantrhrocyadins (PAC) thought to prevent UTI and may not be reliable for that reason.
Recent evidence supports the use of D-mannose, a sugar which can be taken twice daily by mouth, in reducing the risk of recurrent infections. While not thought to be effective for all types of bacteria, it is likely to be active against the most common types of bacteria causing urinary tract infections. My clinical experience with D-mannose with hundreds of patients over several years suggests that it has a significant impact on the rates of urinary tract infections. I recommend this for most of my recurrent UTI patients.
In some women, the use of longer courses of low-dose antibiotics may provide benefit. While these preventative (prophylactic) antibiotics reduce the occurrence of infections while the medication is taken, risk of infection typically returns upon stopping. There are risks of side effects (some severe) from these longer courses and there is no evidence supporting taking antibiotics in this way for multiple years. I uncommonly use low-dose prophylaxis in my recurrent UTI patients and typically only for 3-6 months.
Women who have undergone menopause or who are near menopause can see a reduction in the frequency of infection by using estrogen applied directly to the vagina. Risks are lower than those of estrogen taken by mouth because absorption by the rest of the body of vaginal estrogen is low. Even women with a history of breast cancer may discuss use of vaginal estrogen with their oncologist.
Recurrent UTI represent a significant problem for millions of women in which the antibiotic treatment of the last infection can contribute to development of the next infection by harming normal bacteria which live in the vagina and bladder. Patients benefit from an evaluation that rules out complicating factors and women without these factors do not require longer courses of antibiotics for treatment of infections. There are various means of prevention of recurrent UTI including use of antibiotic prevention but also use of non-antibiotic agents including cranberry juice, D-mannose, and vaginal estrogen.