Because urinary tract infections (UTIs) affect about half of women at some point during their lifetime, they’re a major burden on global healthcare. What’s more, 1 in 4 women with a UTI will experience a recurrent infection within six months and 50 percent will have one within a year. This problem is exacerbated by increasing antibiotic resistance because typical treatments will often just stop working.
This clinical challenge was the inspiration for a recent study conducted by the the University of Queensland in Australia and published in Nature Communications.
What Did the Study Find?
Researchers found that a single strain of bacteria can cause multiple UTIs, which paves the way for new treatments designed to meet the needs of individual patients.
To come to this conclusion, the study followed one woman who suffered from long-term, recurrent UTIs for roughly 45 years — since 1974. The longest she’d ever gone without a UTI was nine months, and she’d taken many different antibiotics. UTIs are one of the most common bacterial infections in humans, and recurrent UTIs are caused by the reintroduction of bacteria into the urinary tract or the resurgence of bacterial reservoirs after a previous UTI has resolved, the authors note.
Researchers isolated E. coli from the woman’s urine during a UTI and determined its entire DNA sequence. The analysis showed that the bacteria causing the recurring UTIs were identical. As co-author Mark A. Schembri, PhD, professor in the University of Queensland’s School of Chemistry and Molecular Biosciences explains it, the same bacteria had survived and escaped treatment.
Why Does the Study Matter?
UTIs are one of the most common bacterial infections in humans, and recurrent UTIs are caused by the reintroduction of bacteria into the urinary tract or the resurgence of bacterial reservoirs after a previous UTI has resolved, the authors note.
As a result of this study, it will be “possible” to create more effective treatments for “some patients,” Dr. Schembri tells Florence Health. “For example, if the same strain keeps causing recurrent UTI, and it is also identified in the intestinal microbiome, then we could design tailored treatment to eliminate the bacteria from not just the patient’s urine, but also the intestinal reservoir that seeds the recurrent UTI.”
Perhaps one of the biggest learnings from the study? “We now know that bacteria can reside in the intestine for very long periods and cause recurring UTIs, despite antibiotic treatment,” said co-author Scott Beatson, an associate professor at the University of Queensland, in a statement.
What Should Clinicians Know About This Study?
The results of the study indicate that “patients suffering recurrent UTIs will likely be infected by bacteria resistant to multiple antibiotics,” Schembri says. Therefore, clinicians should “practice careful monitoring of antibiotic use.”
“If the patient suffers recurrent UTI caused by the same strain, as was the case for our patient, then this highlights a likely reservoir as the source of the repeat infections,” he explains. “If recurrent UTIs are caused by different organisms, then other underlying conditions that might predispose the patient to repeat infection need to be investigated.”
Beatson added: “It’s time we consider using antibiotics that will not just treat the UTI in the bladder, but also eliminate the infection reservoir in the intestine that seeds recurrent infection of the bladder.”
Population dynamics of an Escherichia coli ST131 lineage during recurrent urinary tract infection. Nature Communications.
Last updated 8/23/2019