Evaluation of adenosine deaminase in the diagnosis of pleural tuberculosis: a Brazilian meta-analysis.

OBJECTIVE To evaluate Brazilian studies by summarizing the accuracy of adenosine deaminase in the diagnosis of pleural tuberculosis, with the objective of lending support to the movement to make the test part of the routine investigation of pleural effusions. METHODS A search for Brazilian studies related to the determination of adenosine deaminase levels in the pleural liquid was carried out. These studies were evaluated and included in this study. The data were analyzed using summary receiver operating characteristic (SROC) curves, which enabled the studies to be collected and evaluated regarding the accuracy of the diagnosis. As for the global values of sensitivity and specificity, the Bayes' theorem was applied to calculate the post-test probabilities in different prevalences of the disease. RESULTS Twenty-five studies dating from 1987 to 2005 and including enough information to be used in the meta-analysis were identified. After evaluation, nine studies were included, totaling 1674 patients. According to the SROC curve, a sensitivity of 91.8% (95% CI: 89.8-93.6%) and a specificity of 88.4% (95% CI: 86.0-90.5%) were found, with an area of 0.969 below the curve. The overall odds ratio was 112.0 (95% CI: 51.6-243.2). Considering a prevalence of tuberculosis of 50% (considered neutral), the post-test probability was 88.7% for a positive test and 91.5% for a negative test. CONCLUSIONS Despite the differences found among studies, it is possible to conclude that the determination of adenosine deaminase levels has high accuracy in the diagnosis of the pleural tuberculosis and should be used as a routine test in its investigation.