Erysipelothrix rhusiopathiae Prosthetic Joint Infection of the Knee in an Immunocompromised Patient.

A male in his 70s with a remote history of a left total knee arthroplasty presented with acute left knee pain and swelling. He was a farmer with significant exposure to domestic and feral swine. CT of the knee showed a large complex left knee effusion and knee aspiration was concerning for infection. He underwent a debridement, antibiotics, and implant retention (DAIR) surgical procedure. Synovial fluid and operative cultures ultimately yielded Erysipelothrix rhusiopathiae, likely acquired from his animal exposures. He completed six weeks of intravenous daptomycin, followed by oral cefadroxil to complete a total of six months of antimicrobial therapy from the time of surgery. He had an excellent functional outcome with no recurrent infection at two years.