Adenosine deaminase activity in pleural fluid--a diagnostic test of tuberculous pleural effusion.

ABSTRACT

Adenosine deaminase (ADA) activity in pleural fluids was studied in 47 patients with pleural effusion of different etiology. Patients were divided into two groups Group I - Tuberculous pleural effusion (21 patients) Group II - Non tuberculous effusion (26 patients) and these included malignant pleural effusion (9 cases), synpneumonic pleural effusion (9 cases) and transudative pleural effusion (8 cases). The mean ADA activity was 64.67 IU/L +/- 21.68 in group I and 6.99 +/- 3.69 in Group II. Increased mean pleural fluid ADA activity in tuberculous pleural effusion was highly significant (p < 0.001) when compared with pleural effusion of non-tuberculous etiology. Based on lowest value of ADA activity found in tuberculous pleural effusion (30 IU/L), the test has a sensitivity and specificity of 1.