Screening for infection before revision hip arthroplasty: A meta-analysis of likelihood ratios of erythrocyte sedimentation rate and serum c-reactive protein levels

Introduction: Diagnosing periprosthetic joint infection (PJI) before revision hip arthroplasty is critical to ensure effective treatment of patients undergoing surgery for reasons other than infection. The main objective of our study is to determine whether the erythrocyte sedimentation rate (ESR) and the serum C-reactive protein (CRP) level are sufficient to use for testing to rule out infection in patients undergoing revision hip surgery. Methods: We performed a systematic review of the literature in the MEDLINE, Ovid, and Embase databases. We included studies in which the investigators used the ESR (>30 mm/h) and serum CRP level (>10 mg/L) for the diagnosis of PJI of the hip. We obtained meta-estimates of sensitivity, specificity, positive likelihood ratio (LR1), and negative likelihood ratio (LR2). Results: From 511 articles, we analyzed 12 studies in which the investigators reported data on 2,736 patients. Sensitivity and specificity for theESRwere 0.860 (95% confidence interval [CI], 0.825 to 0.890) and 0.723 (95% CI, 0.704 to 0.742), respectively, and for the CRP level were 0.869 (95% CI, 0.835 to 0.899) and 0.786 (95% CI, 0.769 to 0.803), respectively. For the ESR, LR1 was 3.42 (95% CI, 2.55 to 4.59) and LR2 was 0.22 (95% CI, 0.12 to 0.41). For the CRP level, LR1 was 4.18 (95% CI, 3.42 to 5.11) and LR2 was 0.20 (95% CI, 0.12 to 0.32). Discussion: With a low pretest probability of PJI, a negative test result for either the ESR or CRP level is enough to rule out infection before revision hip arthroplasty.