What Is The Optimal Post-Op Antibiotic Course For Osteoarticular Infections After Implant Removal?

How long should patients be on antibiotics after the removal of infected hardware? A recent published study in the Journal of Antimicrobial Chemotherapy addresses this important issue.¹

In a single-center prospective study, Benkabouche and colleagues compared four weeks versus six weeks of targeted systemic post-op antibiotics after the removal of infected implants in 123 patients (with 92 percent of the patients being immunocompromised). Sixty-two patients received four weeks of antibiotics and 61 patients were in the group receiving six weeks of antibiotics, according to the study. The most common types of infection included: prosthetic joint infection (38 patients), orthopedic plate infection (44 patients) and infected nail implants (11 patients). 

After a median follow-up period of 2.2 years, 120 episodes (98 percent) were cured microbiologically and 116 (94 percent) were cured clinically.¹ The study team found no statistically significant difference in the rates of clinical or microbiological remission between the groups receiving four and six weeks of antibiotic therapy. 

This was an important study because it essentially. showed that for patients otherwise appropriately treated for osteomyelitis, there appears to be no difference between parenteral antibiotics and oral agents. So, if our patient has a functioning gut, we should feel very comfortable treating that patient with an appropriately directed oral antibiotic. I definitely feel this data is transferable to many clinical scenarios that we treat, not only here at the Southwestern Academic Limb Salvage Alliance (SALSA) at the University of Southern California (USC), but around the world. It specifically can be important for diabetic foot complications with potential osteomyelitis. 

I also believe that thisfits the overall theme of better antimicrobial stewardship. This is a big idea because we are in an antimicrobial “arms race” and these bacteria are smarter than we are. However, we need to try to be at least as clever. This is part of how we can do that in giving the least amount of antimicrobial therapy patients need to get them back to living their lives. It is not giving them the most antibiotics because these agents are not trivial. When we treat people with these antimicrobials, it is the equivalent of giving them chemotherapy. They can cause ototoxicity, acute nephrotoxicity and other types of problems. We must keep in mind that we are changing the patient’s microbiome so we have to be more judicious in our choices. 

Dr. Armstrong is a Professor of Surgery at Keck School of Medicine at the University of Southern California. He is the Director of the Southwestern Academic Limb Salvage Alliance (SALSA). 

Editor’s Note: This blog originally appeared at https://diabeticfootonline.com/2019/06/01/four-versus-six-weeks-of-antibiotic-therapy-for-osteoarticular-infections-after-implant-removal-a-randomized-trial-whats-the-verdict/. It is adapted with permission from the author.

Reference

1. Benkabouche M, Racloz G, Spechbach H, Lipsky B, Gaspoz J-M, Uçkay I. Four versus six weeks of antibiotic therapy for osteoarticular infections after implant removal: a randomized trial. J Antimicrob Chemother. 2019. doi: 10.1093/jac/dkz202. [Epub ahead of print] Accessed June 25, 2019.