Most surgical patients with a history of penicillin allergy can safely be given the guideline-recommended antibiotic cefazolin to prevent infection instead of several penicillin alternatives that are less effective and more expensive, according to a study published in JAMA Surgery.
The study found that the frequency of allergies to both penicillins and cefazolin was so small that most patients should receive cefazolin regardless of their allergy history.
“Under current practice, the roughly 10% of US patients reporting a penicillin allergy are less likely to receive cefazolin at the time of surgery and more likely to receive clindamycin or vancomycin, which increases their risk of developing a surgical infection,” said Kimberly Blumenthal, MD, Massachusetts General Hospital, Boston, Massachusetts. “Our study found that the frequency of dual allergies to penicillin and cefazolin was so small — 0.7% — that surgeons and anaesthesiologists should feel confident giving cefazolin to nearly all patients with a penicillin allergy history.”
Avoidance of cefazolin in patients with penicillin allergy is grounded in research from the 1960s and 1970s that reported a cross-reactivity rate of 8% between penicillins and cephalosporins like cefazolin.
In the current meta-analysis of 77 studies involving 6,147 patients, investigators conducted the most extensive review to date of the frequency of cross-reactivity, with an eye toward improving the perioperative administration of infection-fighting antibiotics.
“We found that that avoidance of cefazolin based on 50-year-old data is unnecessary and, in many cases, ill-advised,” said co-author Meghan Jeffres, PharmD, University of Colorado Anschutz Medical Campus, Aurora, Colorado. “Not only is cefazolin safe for nearly all patients with penicillin allergy, but also, studies have shown that it’s well tolerated and has the appropriate spectrum of activity against organisms commonly encountered in surgical site infections.”
The study showed that the occurrence of dual allergy between penicillin and cefazolin was higher among patients whose penicillin allergy had been confirmed through testing (3%) compared with those with self-reported penicillin allergy (0.7%).
“Surgeons and anaesthesiologists know that the more patients who receive cefazolin, the lower that rate will be,” said Dr. Jeffres. “We believe our study takes a huge step toward providing them with the data and the evidence they need to make well-informed antibiotic decisions for their patients.”