The most common bacterial infections in women of all ages are those that affect the urinary system.
In 30% to 44% of these women, the infection is not cured with the initial treatment, leading to a recurrence within six months of the initial infection. In fact, despite the widespread belief that the cause is anatomical, experts point out that healthy women with normal urological anatomy represent the majority of patients with recurrent urinary tract infections.
“A recurrent urinary tract infection is usually defined as the reappearance of 3 or more episodes within a year, or 2 or more within six months. Escherichia coli causes approximately 75% of recurrent UTIs, while high rates of infections are also caused by Enterococcus faecalis, Proteus mirabilis, Klebsiella, or Staphylococcus saprophyticus. The type of microbe that caused the initial infection is usually also responsible for recurrences,” explains surgeon urologist-andrologist Dr. Markos Karavitakis. The most common symptoms of recurrent infections are dysuria, i.e., difficulty initiating urination, frequent urination, and stranguria, i.e., painful urination.
Diagnosis is made after taking the patient’s medical history and performing a clinical examination. A urinary tract infection should be confirmed with at least one urine culture to verify the diagnosis and determine the appropriate treatment. Beyond these, further evaluation is useful when findings from the history or examination suggest a complicated infection or another disease.
What, then, are the risk factors for recurrent urinary tract infections?
According to Dr. Karavitakis, independent risk factors in premenopausal women include sexual intercourse 3 or more times per week, spermicide use, having new or multiple sexual partners, and a history of UTI before the age of 15. In postmenopausal women, estrogen deficiency and urinary retention are strong factors.
Frequent sexual intercourse causes contamination of the urethra and bladder by bacteria living in the intestine, while spermicide use disrupts the healthy Lactobacillus flora of the vagina, thereby allowing uropathogens to increase. In premenopausal women, sexual intercourse three or more times a week triples the risk. “Body mass index, wiping technique after defecation, and frequent tampon use have not been proven to be risk factors. Similarly, hot baths, showers, increased fluid intake, and the use of cotton underwear have no effect on the risk of UTI recurrence, according to studies.
However, post-coital urination, although it appears to have a small protective effect, is a logical and safe practice,” notes Dr. Karavitakis. “Other risk factors in postmenopausal women include incontinence, cystocele, type 1 or 2 diabetes mellitus, as well as a history of more than five UTIs. Activities that increase intra-abdominal pressure (e.g., long-distance hiking) may worsen incontinence, cystocele, or lead to post-void residual urine, and may be predisposing factors for the occurrence of recurrent UTIs in women who engage in these activities,” he adds.
Is the predisposition to UTIs hereditary?
Hereditary factors appear to influence a woman’s susceptibility to multiple episodes. Having a first-degree relative with a history of five or more UTIs is a risk factor for recurrent urinary tract infections. “Specific inheritance patterns may reduce the immune system’s ability to clear bacteria or prevent their adhesion to the uroepithelium,” he further explains. Additionally, differences in urogenital tract anatomy, including a short urethral-anal distance, may predispose some women to UTIs.
When is further clinical evaluation recommended?
As Dr. Karavitakis clarifies, a history suggesting simple cystitis in patients with a previously confirmed UTI is usually sufficient for diagnosing recurrent infection. Clinical examination, laboratory, and imaging tests have limited utility and are generally not recommended.
What are the benefits of patient-initiated treatment?
Patient-initiated treatment for recurrent urinary tract infections reduces diagnostic costs, the number of medical visits, and the number of days patients suffer from symptoms, compared to physician-initiated treatment. However, it does not achieve a reduction in recurrences. Also, antibiotic prophylaxis effectively limits UTI recurrence but increases the risk of antibiotic resistance and adverse effects.
How can I protect myself?
Daily or post-coital low-dose antibiotic prophylactic regimens reduce the recurrence of symptomatic UTIs by approximately 95%, although patients may return to pre-prophylaxis recurrence rates once drug therapy is discontinued.
Are there alternative therapeutic strategies to limit antibiotic use?
Taking analgesics or anti-inflammatory drugs to manage UTI symptoms can limit antibiotic use in willing patients when closely monitored by their treating physician. Delaying the initiation of antibiotic therapy until urological test results are available in patients with typical symptoms is not recommended.
As an alternative to antibiotics, the doctor may suggest cranberry products, which can reduce recurrent UTIs in premenopausal women, but are less effective than antibiotic prophylaxis. However, data from studies are conflicting, and the optimal dosage is unknown. Finally, postmenopausal women with atrophic vaginitis may benefit from local estrogen therapy.