[The usefulness and limitations of adenosine deaminase in the diagnosis of tubercular pleurisy. A meta-analytical study].

To assess the yield of adenosine deaminase (ADA) measurement in the diagnosis of tuberculous pleuritis and to afford parameters applicable to different populations and risk groups, a meta-analysis was performed in this study. National and anglo-saxon studies included in the Index Medicus from 1980 to march of 1990 were reviewed. The estimated incidence of tuberculous pleuritis in our medium was about 0.18 (confidence intervals for 95%-95% CI: 15-0.21). The diagnostic yield of ADA was as follows: sensitivity of 0.99 (95% CI: 0.98-0.99) and specificity of 0.93 (95% CI: 0.91-0.94). The quotients of probability (parameters that measure the predictive values of the tests at any given prevalence) were 14.31 and 0.004 for the positive and negative tests, respectively. In or medium the positive and negative predictive values were 0.74 (95% CI: 0.68-0.81) and 0.99 (95% CI: 0.98-0.99), respectively. An ADA value below the discriminative level nearly rules out the existence of tuberculous pleuritis, whereas at the contrary, and ADA value above the discriminative point offers a limited information about the etiology of the pleural effusion.