Standard antibiotics may not help C. diff infections.
Standard course of antibiotics might not be the best method to treat Clostridium difficile (C. difficile) infection, according to a new report.
Researchers from the University of Utah analyzed the use of metronidazole hydrochloride for the treatment of C. difficile infected patients to evaluate the risk of recurrence and all cause 30-day mortality. The researchers compared these outcomes to that of patients treated with vancomycin hydrochloride.
Although metronidazole is considered a go-to therapy for the infection, the team acknowledged that it is inferior to vancomycin for the same treatment.
"For many years the two antibiotics were considered to be equivalent in their ability to cure C. difficile and prevent recurrent disease," the study’s lead author, Vanessa Stevens, PhD, said in a press release. "Our work and several other studies show that this isn't always the case."
The team retroactively examined patients’ records collected from the US Department of Veterans Affairs health care system between January 1, 2005 and December 31, 2012. More than 47,000 C. difficile infected patients were selected for the investigation, while approximately 10,000 were included in the final analysis.
About 5% of the participants (2,068 patients) were administered vancomycin as their first round of treatment. The researchers then matched these patients to 8,069 patients treated with metronidazole for their first round of treatment. Of these patients, the researchers categorized 5,452 as having mild to moderate C. difficile infection while 3,130 were classified as severe cases.
The researchers determined that there were no differences in the risk of recurrence between metronidazole treated and vancomycin treated patients. This remained true even when the researchers examined the effects through the lens of the patients’ disease severity.
Patients with severe C. difficile infection who received vancomycin treatment showed a reduced risk of mortality, the investigators learned. In patients with mild to moderate C. difficile infection, there appeared to be no significant difference in all cause mortality between the metronidazole and vancomycin treated groups.
"This research shows that if providers choose vancomycin over metronidazole to treat patients with severe CDI, it should result in a lower risk of death for those critically ill patients,” said researcher Michael Rubin, MD, PhD. He called antibiotics once of the greatest miracles of modern medicine, but said that vast gaps of knowledge exist about when and how to use them in order to produce the best outcomes for patients.
The study authors acknowledged that one of the primary limitations of the study was that the participants were primarily men; however, they explained that previous studies on C. difficile infection concluded that the treatments for men and women are alike.
"The optimal way to move forward is to do decision analysis that allows us to weigh the pros and cons of the various treatment strategies," Stevens concluded.
The paper, titled “Comparative Effectiveness of Vancomycin and Metronidazole for the Prevention of Recurrence and Death in Patients With Clostridium difficile Infection,” was published in JAMA.