Rendimento da atividade da adenosina desaminase comparado com histopatológico de biópsia pleural fechada em pacientes com tuberculose pleural Adenosine deaminase test in comparison to histophatology from closed pleural biopsy in patients with pleural tuberculosis

Introduction: conventional methods for the diagnosis of pleural tuberculosis have proven inefficient. A pleural biopsy specimen with histopathologic criteria has greatest utility, with higher sensitivity. However, this procedure requires greater expertise and is more invasive. Mycobacterium tuberculosis in cultured pleural fluid permit firm diagnosis, but, sensitivity is low and results can take as long as six weeks to arrive. Individually, the measurements of ADA activity in pleural liquid (L-ADA) has proven to be sensitive and specific for pleural tuberculosis. However, these diagnostic aids have not being widely utilized for the routine laboratory diagnosis. The objective was to compare L-ADA to histopathlogical evaluation from pleural biopsy in tuberculous pleural effusion. Methodology: a prospective within- subject design was used. Forty pleural liquids and forty pleural biopsy specimens. Dosage of L-ADA for the technique of Giusti and Galanti. Comparisons between sensitivity of the diagnostic methods were performed using McNemar test. H 0 was reject if p < 0.05. Sensitivity (S p ) of tests were used in a parallel combination. Tetrachoric coefficient (r tet ) was used for correlation. Results: sensitivity was 77.5% (CI95% 63.0 - 88.0) and 57.7% (CI95% 41.0 - 70.0) to the tests of L-ADA and pleural histopathology, respectively (χ 2 mc = 1.565; p = 0.2109). S p was 90.5% (CI95% 81.5 - 99.5) and the value of the tetrachoric correlation coefficient (r tet ) was 0.607. Conclusion: for diagnosis of tuberculous pleural effusion, adenosine deaminase in pleural fluid has a better sensitivity than histopathological study from closed pleural biopsy and must be widely utilized for the routine diagnosis.