Table 3.
Diagnostic value of the markers for PJI
| Markers | AUC (95% CI) | Youden index | Optimal cutoff value | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | Pa | Pb |
|---|---|---|---|---|---|---|---|---|---|
| CRP (mg/L) |
0.848 (0.788–0.907) |
0.686 | 8.15 | 83.5 | 85.0 | 77.6 | 89.3 | ||
| ESR (mm/h) |
0.865 (0.813–0.918) |
0.616 | 15.70 | 88.6 | 75.4 | 70 | 91.5 | ||
| PLT (× 109/L) |
0.727 (0.657–0.796) |
0.359 | 241.5 | 65.8 | 70.1 | 57.8 | 76.7 | 0.009 | 0.002 |
| PCT (%) |
0.706 (0.633–0.779) |
0.321 | 0.236 | 68.4 | 63.8 | 54.0 | 76.4 | 0.003 | 0.0005 |
| PMR |
0.718 (0.648–0.788) |
0.353 | 25.31 | 62.0 | 73.2 | 59.0 | 75.6 | 0.006 | 0.001 |
| GLB |
0.784 (0.719–0.849) |
0.476 | 30.65 | 80.0 | 71.7 | 75.9 | 72.4 | 0.157 | 0.049 |
| AGR |
0.826 (0.770–0.880) |
0.398 | 1.165 | 67.1 | 86.7 | 67.1 | 80.3 | 0.594 | 0.308 |
| PLT/AGR |
0.844 (0.791–0.898) |
0.585 | 188.9 | 86.1 | 76.4 | 86.1 | 72.4 | 0.937 | 0.586 |
PJI, periprosthetic joint infection; CI, confidence interval; AUC, area under the curve; PPV, positive predictive value; NPV, negative predictive value; ESR, erythrocyte sedimentation rate; CRP, C-reactive protein; PLT, platelet count; MPV, mean platelet volume; PCT, plateletcrit; PMR, PLT to MPV ratio; GLB, globulin; AGR, albumin to globulin ratio
aCompared with the AUC of CRP
bCompared with the AUC of ESR