Pleural fluid ADA activity has been shown to be a valuable biochemical marker that has a high sensitivity and specificity for pleural tuberculosis diagnosis.7 The mean ADA values among the confirmed pleural tuberculosis and unconfirmed cases in our study were 52.2 ± 21.66 units/L and 50.12 ± 21.77 units/L respectively, which were both significantly higher than that of the control group (12.70 ± 8.64 units/L), with a p value of less than 0.0001. This evidence concerns the gene ADA and pleural tuberculosis.