Comparison of culture and broad-range polymerase chain reaction methods for diagnosing periprosthetic joint infection: analysis of joint fluid, periprosthetic tissue, and sonicated fluid

This study compared the diagnostic capabilities of culture and broad-range polymerase chain reaction (PCR) using joint fluid (JF), periprosthetic tissue (PT), and sonicated fluid (SF) for the diagnosis of periprosthetic joint infection (PJI). Sixty-seven subjects underwent knee or hip revision surgery, with 53 PJI and 14 aseptic failure (AF) cases included retrospectively. JF, PT, and SF samples were collected after a suspension of antibiotics more than two weeks, and culture and broad-range PCR were performed for all samples. The sensitivities of SF culture (83.0%), JF-PCR (83.0%), and SF-PCR (84.9%) were similar (P > 0.05), but each was significantly more sensitive than JF culture (69.8%), PT culture (71.7%), and PT-PCR (34.0%) (P < 0.05). The specificities of JF culture, PT culture, SF culture, JF-PCR, PT-PCR, and SF-PCR were similar (100, 100, 85.7, 85.7, 100, and 78.6%, respectively) (P > 0.05). PCR was unable to accurately detect six polymicrobial infections and two fungal infections. SF culture, JF-PCR, and SF-PCR were more sensitive than JF culture, PT culture, and PT-PCR for diagnosing PJI among patients who have stopped taking antibiotics for two weeks or more. Compared with PCR methods, SF culture has the advantage of detecting polymicrobial or fungal infections. PT-PCR proved to be insufficiently sensitive for providing correct diagnoses.