RESUMO
PURPOSE: The aim of this study is to evaluate the value of pleural adenosine deaminase (ADA) in differentiating tuberculous pleural effusion from non tuberculous pleural effusion of children. METHODS: We measured pleural ADA activity in patients with pleural effusion whose age were from seven months to seventeen years from January 1995 to October 2001. By some criteria the patients were grouped to tuberculous pleural effusion, bacterial effusion, mycoplasma effusion, malignant effusion, and other effusion. RESULTS: The mean pleural ADA activity in tuberculous pleural effusion was 86.2+/-27.3 U/L. Pleural ADA activities in bacterial effusion, mycoplasma effusion, malignant effusion, other effusion were 32.6+/-20.1, 22.1+/-15.4, 23.1+/-10.9, 36.7+/-28.4 U/L, respectively. Pleural ADA activity in tuberculous pleural effusion was significantly higher than in any other group(P<0.001). At a level of 50 U/L, the sensitivity, specificity, positive predictive value (ppv), and and negative predictive value(npv) for the identification of tuberculous pleural effusion from nontuberculous pleural effusion were calculated at 93.8%, 84.8%, 81.1%, 95.1%, respectively. CONCLUSION: Pleural ADA is a useful test in the diagnosis of tuberculous pleural effusion of children from nontuberculous pleural effusion.