Report of a case of migrating periprosthetic infection from a hip replacement to a contralateral knee joint undergoing a total knee replacement.

We present a 74-year old female patient who underwent a total hip arthroplasty of the left hip after a subcapital fracture of the femur. Four months after the index procedure the patient presented with signs and symptoms of infection of the operated joint. Staph aureus and Enterococcus faecalis were recognized as the infecting bacteria. The implants were removed, cement spacers were placed and a total hip arthroplasty was performed again after three months. Unfortunately, infection ensued again and the patient underwent three more procedures until the joint was considered clean and t he hip remained flail without implants. The patient elected to undergo a total knee arthroplasty due to severe osteoarthritis of right knee. Intraoperatively tissue samples were taken and sent for cultures which identified Enterococcus faecalis present in the knee joint. Enterococcus migrated from the infected hip to nonoperated knee joint. Intravenous antibiotics were administered for three weeks but the knee presented with infection of the arthroplasty ten months after its insertion. The implants were removed the joint was debrided and cement spacers were inserted.

The patient decided not to proceed with another procedure and she remains with the cement spacers in her knee.

Rare report of migrating periprosthetic infection. Nosocomial enterococci acquired resistance cannot be ruled out. Unique characteristics in enterococci antibiotic resistance and biofilm formation.