The diagnosis of tuberculous pleural effusion maybe definitively established via demonstration of Mycobacteriumtuberculosis in the pleural fluid or a pleural biopsy specimen.Measurement of adenosine deaminase (ADA) and interferon-gammaassay in the pleural fluid has also gained wide acceptance in thediagnosis of TB pleural effusions in developed countries.[4] However,these tests are not readily available in most developing countries,including Ethiopia. This evidence concerns the gene ADA and tuberculosis.