Journal of clinical microbiology 2018 02 14() pii 10.1128/JCM.01351-17
Prosthetic joint failure is mainly caused by infection, aseptic failure (AF), and mechanical problems. Infection detection has been improved with modified culture methods and molecular diagnostics. However, comparisons between modified and conventional microbiology methods are difficult, due to variations in specimen sampling. In this prospective, multidisciplinary study of hip or knee prosthetic failures, we assessed the contributions of different specimen types, extended culture incubations, and 16Ssequencing for diagnosing prosthetic joint infections (PJI). Project specimens included joint fluid (JF), bone biopsies (BB), soft tissue biopsies (STB), and swabs (SW) from the prosthesis, collected, and sonication fluid collected from prosthetic components (PC). Specimens were cultured for 6 (conventional) or 14 days, and 16Ssequencing was performed at study completion. Of the 156 patients enrolled, 111 underwent 114 surgical revisions (cases) due to indications of either PJI (n=43) or AF (n=71). Conventional tissue biopsy cultures confirmed PJI in 28/43 (65%) cases and refuted AF in 3/71 (4%) cases; one case was not evaluable. Based on these results, minor diagnostic adjustments were made. Fourteen-day cultures of JF, STB, and PC specimens confirmed PJI in 39/42 (93%) cases, and 16Ssequencing confirmed PJI in 33/42 (83%) cases. One PJI case was confirmed with 16Ssequencing alone, and five with cultures of project specimens alone. These findings indicated that JF, STB, and PC specimen cultures qualified as an optimal diagnostic set. The contribution of sequencing to diagnosis of PJI may depend on patient selection; this hypothesis requires further investigation.