Extended Antibiotic Spacer use in an Infected Total Knee Arthroplasty with Mycobacterium intracellulare - A Case Report.

Introduction: Mycobacterium infections are a rare but devastating cause of prosthetic joint infection (PJI). Most cases of non-tuberculous mycobacteria infections occur in immunocompromised hosts, a population increasing with the use of immunosuppressive medications such as biologics. We describe a unique case of a healthy patient with an infected total knee arthroplasty (TKA) found to be colonized by the rare Mycobacterium avium intracellulare, who ultimately had an antibiotic spacer retained for 18 months before second-stage revision surgery. Case Report: The patient was an immunocompetent 41-year-old female with an infected TKA with the rare Mycobacterium avium intracellulare infection. She ultimately needed a two-stage revision surgery, where she had a retained antibiotic spacer for an extended period of 18 months before reimplantation surgery. Conclusion: Mycobacterium intracellulare is a very rare organism seen with infection of total joint arthroplasty. Careful workup and infection management are critical to providing the best patient results. Antibiotic spacers are very useful in managing infected total joint arthroplasties. Ultimately, prolonged antibiotic spacer usage can be an effective strategy for orthopedic surgeons to address rare organisms with infected total joint arthroplasties.