Extra antibiotics to prevent joint replacement infections don't help: trial

A clinical trial involving 4239 patients in 11 hospitals across Australia has found that in joint replacement infections, the addition of vancomycin does not protect against infection and may lead to more infections and more adverse reactions for the patients.

Led by Monash University researchers, in collaboration with orthopaedic surgeons and infectious diseases doctors, the trial involved patients without a history of MRSA (methicillin resistant Staphylococcus aureus, or “golden Staph”).

An antibiotic, cefazolin, is used at the time of surgery to prevent infection. But with the rise of antibiotic-resistant bacteria, experts have debated whether adding a second antibiotic, vancomycin, would be better to prevent more infection. Vancomycin is a commonly used antibiotic for MRSA.

As a part of the trial, participants were randomised to receive either vancomycin or saline placebo, in combination with cefazolin.

Among all patients, the addition of vancomycin was no better than the traditional cefazolin antibiotic. Unexpectedly, in patients undergoing knee joint replacement, the risk of infection was higher in the vancomycin group, 5.7%, than in the placebo group, with 3.7% infection rate.

According to the study lead, Professor Trisha Peel, from the Monash University Central Clinical School, “Given the number of joint replacements performed in Australia and globally, our trial has answered the important question about whether more antibiotics are better for our patients having joint replacement surgery: with the definitive answer being ‘no’. This trial will have a significant impact on practice.”

Professor Peel said that the study reflects how important these large, randomised, multi-centre clinical trials are: “This is one of those cases — more antibiotics weren’t better, and in some people might have actually been worse.”

The findings have been published in the New England Journal of Medicine.

Image credit: iStock.com/Jaromir Ondra