Role of Thoracoscopy in diagnosis of Tubercular Pleural Effusion in low ADA setting- A Prospective, Observational Study

Tubercular Pleural effusion (TBPE) is one of most common extrapulmonary tuberculosis. It can be difficult to diagnose due to low sensitivity of pleural fluid smear, culture and CBNAAT. Diagnosis of TBPE is then dependent on the level of pleural fluid Adenosine Deaminase (ADA). Thoracoscopic pleural biopsy gives definite diagnosis specially in Low Pleural fluid ADA setting. This study was planned to find out the prevalence of tubercular etiology in patients of exudative pleural effusion with low ADA (ADA < 40 IU/L) A Prospective, observational study was carried out in a tertiary teaching institute in north India. Total 142 patients of pleural effusion with low ADA were enrolled. All patients underwent rigid thoracoscopy for confirmation of their diagnosis. Out of 142 patients, male were 78 (55%) and female were 64 (45%). Mean age of patients were 57.4 years. Tuberculosis was diagnosed as a cause of effusion in 22 (15.5%) out of 142 patients. Majority of TBPE patients had pleural thickening as thoracoscopic finding. Mean ADA level in TBPE was 27.36 ±11.6 as compared to 18.55 ±9.02 in non tubercular pleural effusion patients and this difference was significant statistically (P- 0.002). The diagnosis of patients having exudative, low ADA pleural effusion can be very easily confirmed by thoracoscopy guided pleural biopsy which has a very high diagnostic yield.