[The diagnostic value of adenosine deaminase coefficient in patients with tuberculous exudative pleurisy]

The authors examined 51 patients aged 37.74 +/- 2.17 years who had tuberculous pleurisy and aged 49.8 +/- 4.6 years who had nonspecific pleurisy. Group 1 comprised 18 patients with isolated tuberculous exudative pleurisy. Group 2 included 13 patients with tuberculosis complicated by tuberculous pleurisy. Group 3 consisted of 10 patients with nonspecific exudative pleurisy. Catarrhal endobronchitis was the leading form of tracheo-broncheal tree lesion among patients with tuberculous exudative pleurisy (n = 20 (64.5%)). The activity of adenosine deaminase (ADA) was 2.18 +/- 0.73, 2.41 +/- 0.80, and 2.47 +/- 1.52 U/l in Groups 1, 2, and 3, respectively. Thus, the measurement of bronchoalveolar fluid ADA separately from other parameters is of no informative value in the differential diagnosis of the etiology of pleurisy. While analyzing the parameters, the authors introduced the coefficient of ADA (CADA) that was calculated using the formula: K(ADA) = ADA/cytosis. In patients with tuberculous pleurisy, K(ADA) was 0.65 +/- 0.17 (this was 0.52 +/-0.13 in isolated tuberculous exudative pleurisy and 0.84 +/- 0.36 in tuberculous exudative pleurisy complicated by pulmonary tuberculosis (p < 0.05), and 0.20 +/- 0.06 in nonspecific pleurisy (p < 0.05). The ADA coefficient of 0.52 or more confirms the tuberculous etiology in isolated pleurisies and permits a differential diagnosis to be made between specific and nonspecific pleurisy with and without lung changes.