Evaluation of Gamma-Interferon in diagnosis of Tuberculosis Pleurisy

IntroductionDifferential diagnosis between Tuberculosis pleurisy and Non Tuberculoses pleural effusion can be sometimes difficult and needs invasive diagnostic methods. In recent years, several biological markers have been found to be diagnostic markers of Tuberculosis pleurisy. The aim of this study was assessment of the value of Gamma-Interferon in the diagnosis of TB pleurisy.Materials and Methods We studied 70 patients with pleural effusion who had been admitted to Ghaem hospital, Mashhad University of Medical Sciences, Mashhad, Iran. Interferon gama level was measured by "ELISA" method. The diagnosis of tuberculosis was based on microbiologic study of pleural fluid plus pleural biopsy.Result Altogether Twenty patients had tuberculosis pleurisy (44.44%), 21 patients had malignant pleural effusion (46.67%) and 4 patients had pleural effusion with various non TB non malignant etiologies (8.9%). The sensitivity, specificity of Gamma-Interferon in TB pleurisy were 60% and 96% respectively.ConclusionINFγ is a valuable indicative marker for diagnosis of tuberculosis pleurisies’ but we should consider situations with high level of INFγ without any evidence of TB and also Tuberculsis Pleurisy patients with INFγ level lower than diagnostic threshold.