Study finds why UTI occurs more in postmenopausal women

A study has found why Urinary Tract Infections (UTIs) have a high recurrence rate in postmenopausal women.

The study was published in the journal, 'Journal of Molecular Biology'.

The treatment of UTI is the most common reason for antibiotic prescriptions in older women.

"Recurrent UTI (RUTI) reduces the quality of life, places a significant burden on the health care system, and contributes to antimicrobial resistance," said Dr Kim Orth, senior author of the study.

The investigation demonstrates that several species of bacteria can work their way inside the human bladder's surface area, called the urothelium, in UTI patients. Bacterial diversity, antibiotic resistance, and the adaptive immune response all play important roles in this disease, the study suggests.

"Our findings represent a step in understanding RUTIs in postmenopausal women," said Orth.

"We will need to use methods other than antibiotics to treat this disease, as now we observe diverse types of bacteria in the bladder wall of these patients," she added.

Since the advent of antibiotics in the 1950s, patients and physicians have relied on antibiotics for UTI treatment.

"As time went on, however, major antibiotic allergy and resistance issues have emerged, leading to very challenging and complex situations for which few treatment choices are left and one's life can be on the line," said Dr Philippe Zimmern, one of the senior authors of the research. "Therefore, this new body of data in women affected by RUTIs exemplifies what a multidisciplinary collaboration can achieve going back and forth between the laboratory and the clinic."

UTIs are one of the most common types of bacterial infections in women, accounting for nearly 25 per cent of all infections. Recurrence can range from 16-36 per cent in premenopausal women to 55 per cent following menopause. Factors responsible for higher UTI rates in postmenopausal women include pelvic organ prolapse, diabetes, lack of estrogen, loss of Lactobacilli in the vaginal flora, and increased colonization of tissues surrounding the urethra by Escherichia coli, the research finds.

The team of researchers examined bacteria in bladder biopsies from 14 RUTI patients using targeted fluorescent markers, a technique that had not been used to look for bacteria in human bladder tissue.

"The bacteria we observed are able to infiltrate deep into the bladder wall tissue, even past the urothelium layer," said Dr Nicole De Nisco who initiated the research. We also found that the adaptive immune response is quite active in human RUTIs," Zimmern added.

Accessing human tissue was key, the researchers note, as the field has largely relied on mouse models that are limited to lifespans of 1.3 to 3 years, depending on the breed.

Future studies will focus on determining effective techniques to remove these bacteria and chronic inflammation from the bladder, finding new strategies to enhance immune system response and pinpointing the various bacterial pathogens involved in RUTIs.