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Widespread antibiotic use linked to rise of ‘almost incurable’ superbug

Widespread antibiotic use linked to rise of ‘almost incurable’ superbug

Common antibiotic used for treatment liver disease can lead to “almost incurable” superbugscientists warned in a new study.

antibioticRifaximin contributed to the global emergence of vancomycin-resistant Enterococcus faecium, or VRE, a superbug that often causes serious infections in hospitalized patients, according to an eight-year study published in the journal. Nature.

The international team of researchers who conducted the study warns that the use of rifaximin leads to an increase in illness. bacterial resistance to daptomycin, one of the latest effective treatment options for VRE infections.

The results challenge the long-held belief that rifaximin poses a “low risk” of causing antibiotic resistance.

Antibiotics rifaximin and VRE bacteria on a petri dish (Adrianna Turner)Antibiotics rifaximin and VRE bacteria on a petri dish (Adrianna Turner)

Antibiotics rifaximin and VRE bacteria on a petri dish (Adrianna Turner)

The researchers emphasize the need to better understand the negative consequences of antibiotic use and strengthen their responsible use in clinical practice.

They are concerned that these superbugs may be transmitted to other patients in the hospital.

In the latest study, researchers found changes in the DNA of daptomycin-resistant VREs that were absent in susceptible strains.

Subsequent analysis showed that use of rifaximin caused these changes and triggered the emergence of daptomycin-resistant VRE.

The image shows examples of the spread of antibiotic resistance (Center for Disease Control).The image shows examples of the spread of antibiotic resistance (Center for Disease Control).

The image shows examples of the spread of antibiotic resistance (Center for Disease Control).

Rifaximin causes specific changes in an enzyme called RNA polymerase. These changes lead to a cascade of further changes to the bacterial cell membrane, causing cross-resistance to daptomycin.

“When bacteria become resistant to an antibiotic, it’s a bit like gaining a new ability in a video game, like super speed. But when exposed to rifaximin, VRE bacteria don’t just get one boost—they gain multiple abilities, such as super speed and super strength, allowing them to easily defeat even the final boss,” explained study co-author Adrienne Turner.

“Rifaximin doesn’t just make bacteria resistant to one antibiotic; this may make them resistant to other antibiotics, including important antibiotics of last resort such as daptomycin.”

The study highlights the benefits of using genomic surveillance to identify emerging drug resistance in bacteria.

It says doctors should exercise caution when treating VRE infections in patients taking rifaximin, and drug regulators should consider similar implications when approving antibiotics.

“Rifaximin remains a very effective drug when used correctly, and patients with advanced liver disease who are currently taking it should continue to do so,” said Jason Kwong, another author of the study.

“But we need to understand the implications that will develop both in the treatment of individual patients and from a public health perspective.”