Case: This is the first clinical report of periprosthetic total joint infection caused by Bartonella henselae. A 65-year-old woman developed an acutely painful total knee 3 weeks after a cat scratch. Serial joint aspirations and tissue cultures failed to identify any organism. Diagnosis was performed with polymerase chain reaction analysis. She underwent a 2-stage revision with successful symptom resolution.
Conclusions: Bartonella is an unusual cause of total knee infection requiring alternative techniques for diagnosis because cultures are unlikely to be definitive.