Limited value of Platelet-related markers in diagnosing periprosthetic joint infection

Abstract

Abstract Objective To evaluate the diagnostic values of serum platelet count (PC), mean platelet volume ratio (MPV), platelet count to mean platelet volume ratio (PVR), platelet to lymphocyte ratio (PLR), platelet to neutrophil ratio (PNR), and PC/AGR in the diagnosis of periprosthetic joint infection. Methods The medical records were retrospectively analyzed of the 158 patients who had undergone hip or knee revisions from January 2018 to January 2021. Of them, 79 cases were diagnosed with PJI and 79 with aseptic loosening (AL). PJI was defined using the Musculoskeletal Infection Society criteria. The plasma levels of C-reactive protein (CRP), the erythrocyte sedimentation rate (ESR), the serum platelet count (PC), mean platelet volume ratio (MPV), platelet count to mean platelet volume ratio (PVR), platelet to lymphocyte ratio (PLR), platelet to neutrophil ratio (PNR), and PC/AGR in the 2 groups were recorded and analyzed. The receiver operating characteristic curve was used to calculate the sensitivity and specificity of each indicator. The diagnostic value for each indicator was calculated according to the area under the curve (AUC). Results The PC, PVR, PLR, and PC/AGR levels in the PJI group were significantly higher than those in the AL group (P < .001). The area under the curve of PC/AGR was 0.802, which was slightly lower than that of CRP (0.826) and ESR (0.846). ROC analysis for PC/AGR revealed a cut-off value at 160.63, which provided 84.81% sensitivity and 65.82% specificity for periprosthetic joint infections. The area under the curve of PLR and PC was 0.738 and 0.702. The area under the curve values for PVR, PNR, and MPV were 0.672, 0.553, and 0.544, respectively. Conclusions The results of this study suggest that PC, PLR, and PC/AGR values do not offer significant advantages over ESR or CRP values when employed for the diagnosis of PJI. PVR, PNR, and MPV were not reliable in the diagnosis of PJI.