How do antibiotics change the smell of urine?

Antibiotic resistance: harmless or urinary infection?

Because their urethra is much shorter than that of men, women are about four times more likely to develop cystitis. A team led by microbiologist Evgeni Sokurenko from the University of Washington School of Medicine has now found that antibiotic-resistant intestines are relatively common in women Escherichia coli-Bacteria frolic. The researchers found exactly the same microbes in the urine of more than 40 percent of the test subjects, even though the women did not suffer from cystitis at all at the time of the study. In the journal Clinical Infectious Diseases, the research team reports that certain fluoroquinolone-resistant bacterial strains survived longer in the women's intestines - and smuggled their way into the urinary tract more often than others E. coli- tribes.

Sokurenko's team examined the intestinal flora of over 1,000 women who had been spared from cystitis in the past twelve months. The researchers found bacteria that are resistant to fluoroquinolones in almost nine percent of them. In the past, doctors often prescribed these active ingredients, for example for mild urinary tract infections. Due to their serious side effects, official authorities have restricted the use of gyrase inhibitors more and more in recent years. But the funds have apparently left their mark. The researchers found the multi-resistant bacteria particularly common - at least in comparison to other fluoroquinolone-resistant bacteria E. coliStrains ST1193 and ST131-H30R. According to Florian Wagenlehner, Director of the Clinic for Urology, Pediatric Urology and Andrology at the Giessen University Hospital, the latter is responsible for around ten percent of urinary tract infections in this country. In their study, Sokurenko and his colleagues were unable to identify any direct connection between the use of antibiotics and the first appearance of resistant germs. However, there were only about eight months between the examinations, and only 151 women even provided a second stool sample. In the meantime, fluoroquinolone-resistant bacteria had resettled in the intestines of seven test subjects, five of which were the strains ST1193 and ST131-H30R. Even though none of the women had taken antibiotics in the meantime.

Sokurenko sees the occurrence of resistant germs in the intestines of healthy women as a sign that these strains are superior to others. They linger in our intestines and can spread - even in the absence of the selecting antibiotic. In addition, they apparently cleverly smuggle themselves into the urinary tract: The researchers discovered ST1193 and ST131-H30R in the urine of women twice as often as others E. coli- tribes. However, only 3 of the 45 people who had fluoroquinolone-resistant bacteria in their urine developed cystitis within the next three months. It was already known that bacteria in the urine (bacteriuria) do not always have to be a sign of an acute infection. However, knowing which antibiotics they are resistant to can help defeat them more quickly in an emergency, says Sokurenko.

He considers his method, which he has named and patented as "high-resolution clonal typing", to be suitable for predicting not only a fluoroquinolone resistance, but also other resistances in our intestinal and urinary tract inhabitants. To do this, Sokurenko looks at special areas of the bacterial genome. Up to now, testing for multi-resistant germs (MRE screening) has been quite time-consuming: The gold standard is still the cultivation of isolated bacteria in the presence of various antibiotics. Common molecular biological methods cannot detect many bacterial resistance genes or only very roughly. In addition, it usually takes days before the laboratory results are available - too long in the case of acute cystitis. An effective antibiotic must be found quickly, otherwise the pathogens can reach the kidneys and possibly cause blood poisoning. According to Sokurenko, his new method could also be used to determine antibiotic resistance during an existing infection.

The urologist Wagenlehner currently does not consider preventive microbiome examinations to be useful. It cannot be answered at the moment whether therapeutic interventions will play a role in the future. "Most of the pathogens are still sensitive here in Germany," says Wagenlehner. The resistance rates are around 30 percent. In most cases, the prescribed medication works quickly. If not, switch to another antibiotic - there is still enough choice.