The bacteria responsible for causing most urinary tract infections is becoming resistant to the most common antibiotics, and researchers warn that it may be nearly impossible to identify when alternative treatments should be used.
Approximately 6% of patients with urinary tract infections who visited a Northern California emergency department between August 2016 and July 2017 tested positive for strains of E. coli bacteria that were resistant to ceftriaxone, an antibiotic used routinely to treat a variety of infections. Among patients with a drug-resistant UTI, 78% initially received antibiotic therapies that didn't effectively treat the infection, according to a study published this week in the Annals of Emergency Medicine.
Nearly half of patients that had a drug-resistant UTI hadn't been in another healthcare setting where they could have contracted the bacteria. Their infections were categorized as "community-associated."
Traditionally, the vast majority of these types of drug-resistant infections have emanated from hospitals. But drug-resistant E. coli has spread in community settings throughout Europe, Asia and South America over the past two decades. Studies published in the past several years have shown drug-resistant strains of E. coli are beginning to spread within U.S. communities.
Study lead author Dr. Bradley Frazee, an attending physician at Alameda Health System Highland Hospital, said the findings should serve as a "canary in the coal mine" for providers to take the time to adhere to recommended procedures and protocols when dealing with seemingly routine UTIs, such as performing a urine culture test for all patients with the condition.
"Some of the antibiotics that we routinely use aren't going to adequately treat these drug-resistant bacteria," Frazee said. "The problem that we found was that you can't really identify people very easily who are at increased risk."
Frazee said prescribing an antibiotic for UTIs is still acceptable because drug-resistant E. coli is still relatively rare. But that could be riskier if the UTI is more severe and has formed in the kidneys, which carries risk of permanent kidney damage if not treated quickly.
Using the wrong antibiotic further exposes pathogens to these medications, which can exacerbate antimicrobial resistance.
The study recommended clinicians reconsider routine use of ceftriaxone and follow Infectious Diseases Society of America guidelines for treating bladder UTIs with alternative antibiotics such as nitrofurantoin. Researchers found that was effective in 77% of drug-resistant UTI cases.
Frazee also said providers should consider wider use of urine culture tests and increasing follow-up care for patients. Hospitals can help emergency physicians become more aware of their facility's antibiogram, which helps provide information that shows what antibiotics work against certain bacteria.
But antibiotic stewardship alone is not enough in the fight against antimicrobial resistance. Newer antibiotics need to be developed to address these disease threats, experts say.
It has become more difficult to develop drugs that can keep up with the pace at which pathogens are becoming drug-resistant. Antibiotics also have a poor return on investment compared with chronic disease medications, which gives drugmakers little incentive to develop new treatments.
"Addressing the causes of antibiotic resistance, and developing novel drugs, is imperative," Frazee said. "A society without working antibiotics would be like returning to preindustrial times, when a small injury or infection could easily become life-threatening."