The Diagnostic Value of the Pleural Fluid C-Reactive Protein in Parapneumonic Effusions

Table 2

Receiver operating characteristic curve analysis of the accuracy of biomarkers for identifying parapneumonic effusions.

Biomarker	CRP optimal cut-off value (mg/dL)	Sensitivity; (%)	Specificity (%)	PPV (%)	NPV (%)	AUC
PE^† versus Mal^‡, HF, and LTx	>1.38	84.2	71.5	37.6	96.7	0.85
PE versus LTx	>1.93	75.7	56.5	71.4	61.9	0.67
PE versus Mal	>0.88	87.8	64.7	40.8	95	0.84
PE versus HF	>0.49	93.9	72.7	72	94.1	0.92
HF versus Mal, PE, and LTx	<0.64	79.5	59.4	32.4	92.2	0.76
Emp^£ versus Mal, LTx, and uncomplicated PE	>2.31	83.3%	74.7%	8.3%	99.3%	0.7

^†PE: parapneumonic effusions; ^‡Mal: malignancy; ^£Emp: empyema; HF: heart failure; LTx: lung transplant; PPV: positive predictive value; NPV: negative predictive value; AUC: area under the curve.