Comparative Study of Adenosine Deaminase and Other Conventional Diagnostic Parameters in Diagnosis of Tuberculous Pleural Effusion.

Though pulmonary tuberculosis is the common presentation of Mycobacterium tuberculosis infection, extra-pulmonary tuberculosis is also a growing problem worldwide. Tuberculous pleural effusion is the second frequent form of extra-pulmonary presentation after tuberculous lymphadenitis and if untreated up to 65% of patients with tubercular pleural effusions will eventually develop active TB. Traditional diagnostic methods are very useful for the diagnosis of pulmonary TB but have a low yield when applied to pleural fluid. So,the aim of this study was to evaluate the diagnostic value of ADA level in plural fluid and other conventional methods for diagnosis of tubercular plural effusion. This was a cross sectional study. This study was carried out in 64 Patients suffering from plural effusion and were consecutively selected and divided into two groups: tuberculous (n=40) and non tuberculous (n=24), depending upon etiology. Details clinical history, physical examination, routine and other relevant investigations including ADA estimation was measured. The mean value of ADA in the tuberculous group was 64.11 ± 19.50 U/L which was significantly higher (p<0.05). Cut off value of ADA was ≥ 40 U/L with 97% sensitivity and 93%specificity. In this study, sensitivity, specificity, PPV and NPV of ADA level in pleural effusion were more significant than other conventional parameters.