Vascular endothelial growth factor and proinflammatory cytokines in pleural effusions

To evaluate the predictive value of vascular endothelial growth factor (VEGF) in the differential diagnosis of pleuritis and its association with other proinflammatory cytokines in pleural effusion, we measured VEGF together with interleukin-1beta (IL-1beta), tumor necrosis factor alpha (TNF-alpha) and soluble intercellular adhesion molecule-1 (sICAM-1) in pleural effusions. We investigated 127 patients with pleural effusion (congestive heart failure: 21; parapneumonic: 27; tuberculous: 41; malignant: 38). We examined standard parameters of pleural effusion and measured pleural effusion VEGF, IL-1beta, TNF-alpha and sICAM-1 using enzyme-linked immunosorbent assay. VEGF level was significantly higher in malignant effusion than in other groups. TNF-alpha level was significantly higher in tuberculous pleurisy than in other groups. In tuberculous pleurisy VEGF level showed significant positive correlations with mononuclear cell counts and all investigated cytokines. The sensitivity and specificity of VEGF in the diagnosis of malignancy was 100 and 84%, respectively (cutoff = 2000 pg/ml). The sensitivity and specificity of VEGF and TNF-alpha in the diagnosis of tuberculous pleurisy (VEGF titer <2000 pg/ml and TNF-alpha titer > 55 pg/ml) was 88.9 and 77.1%, respectively. We propose that measurement of VEGF together with TNF-alpha is helpful in differentiating between tuberculous pleurisy and malignant pleural effusion and that VEGF correlates with proinflammatory cytokines especially in tuberculous pleurisy. We also propose that measurement of pleural VEGF is helpful for the diagnosis of malignant pleural effusion.