Out of the 100 patients, 33 had tuberculous pleural effusion and 67 had malignant pleuritis, diagnosed using gold standards. Results: The pleural fluid levels (mean±SE) of ADA in pleural tuberculosis was 58.16 ± 25.8 U / l, compared to 12.83 ± 8.45 U / l in those of malignant pleural effusion.