In this video, Dr. Sunil Dargar, MBBS, MD, Pathologist, New Delhi, talks about the significance of pleural fluid ADA test. Pleural tapping has been sent for ADA test and it is found that the level of ADA test exceeds more than 35 or 100 IU/L as seen in different patients, then it is believed that it is tuberculosis positive. It might be positive or not, because ADA is a substance which is secreted by a lymphocyte when it is reacting. Reactive lymphocytes can be present in various other situations such as sarcoidosis, autoimmune disorders or leukemia or any parasitic infections. Hence, Dr. Dargar informs that the ADA test is not enough to confirm tuberculosis.