Table 2.
Sensitivity, specificity, positive and negative predictive values, and area under the curve for the diagnosis of infectious pleural effusion
| Parameter | Cut off | AUC (CI 95%) | Sensitivity (%) | Specificity (%) | PPV (%) | NPV (%) | LR+ | LR- |
|---|---|---|---|---|---|---|---|---|
| Leukocytes PF | 3380 cells/µl | 0.748 (0.703-0.793) | 55.4 | 84.7 | 53.8 | 85.5 | 3.6 | 0.5 |
| Neutrophils PF | 41% | 0.836 (0.797-0.875) | 71.9 | 84.6 | 63.2 | 89.1 | 4.7 | 0.3 |
| pH PF | 7.37 | 0.736 (0.689-0.784) | 78.8 | 58.9 | 84.2 | 50 | 1.9 | 0.4 |
| LDH PF | 385 IU/L | 0.739 (0.695-0.784) | 78.9 | 57.3 | 37.7 | 89.2 | 1.8 | 0.4 |
| CRP PF | 3.44 mg/dL | 0.845 (0.81-0.88) | 74.5 | 82 | 56.4 | 91.1 | 4.1 | 0.3 |
| PCT PF | 0.13 ng/mL | 0.65 (0.591-0.709) | 65.5 | 63.4 | 31.2 | 87.,9 | 1.8 | 0.5 |
| IL-6 PF | 18,091 pg/mL | 0.763 (0.713-0.812) | 67 | 80 | 50.9 | 88.4 | 3.3 | 4.2 |
| TNF-α PF | 15.4 pg/mL | 0.723 (0.679-0.768) | 75.9 | 60.4 | 37.6 | 88.9 | 1.9 | 0.4 |
| Glucose PF | 223 mg/dL | 0.34 (0.288-0.392) | 4.7 | 96.9 | 33.3 | 75.6 | 1.5 | 1 |
AUC=Area under the curve, CRP=C-reactive protein, IL-6=Interleukin 6, LDH=Lactate dehydrogenase, LR-=Negative likelihood ratio, LR+=Positive likelihood ratio, NPV=Negative predictive value, PCT=Procalcitonin, PF=Pleural fluid, PPV=Positive predictive value, TNF-α=Tumor necrosis factor alpha, CI=Confidence interval