The concentrations of IL-33 in the pleural effusion of the tuberculous group (22.5 ± 0.90 ng/l) were considerably more than that of the malignant group (14.6 ± 2.35 ng/l; P < 0.001) or that of parapneumonic group (7.33 ± 0.32 ng/l; P < 0.001) and transudative group (7.53 ± 0.38 ng/l; P < 0.001), Table 4. This evidence concerns the gene IL33 and Pleural effusion.