Extra pulmonary tuberculosis is a term used to describe isolated occurrence of tuberculosis at body sites other than the lung. Extra pulmonary tuberculosis (EPTB) is also found along various syndromes, the major being the HUMAN IMMUNODEFICENCY Virus (HIV) caused ACQUIRED IMMUNITY DEFICIENCY SYNDORME (AIDS). Before the era of AIDS, it was found out that EPTB constituted about 15 to 20 percent of all cases of TB. In HIV-positive patients EPTB accounts for more than 50 percent of all cases of TB. The diagnosis of EPTB involves deeply located inaccessible areas and hence is very difficult. It is estimated that EPTB constitutes 15 to 20 percent of TB cases in non-HIV infected adults in the country. A higher proportion of cases of EPTB have been registered at tertiary care centres. The commonest sites of EPTB are listed below:Lymphoid glands and tissues and abscesses particularly around the neck.Pleural Fluid EffusionsOrthopedic sites such as bones and jointsGenital and Urinary TractsBloodAbdominal Cavity and PeritoneumPericardiumMeningitisDiagnosis of TB remains challenging because clinical samples have to be obtained from relatively inaccessible sites. These samples may be paucibacillary, thus decreasing the sensitivity of diagnostic tests. The assay of biochemical markers in TB-affected fluids like adenosine deaminase and gamma interferon and molecular biological techniques such as polymerase chain reaction (PCR) maybe useful. Adenosine deaminase is an enzyme involved in purine metabolism that is found in many tissues and particularly in T-lymphocytes by mycobacterial antigens 20- .It has been proposed to be a useful surrogate marker for tuberculosis in body fluids such as pleural, pericardial and peritoneal fluids. Though it should be kept in mind that one should consider the false positive and false negative results.OBJECTIVES:The objective of the study is to establish Adenosine Deaminase as a potential confirmatory test for EPTB. Extra pulmonary tuberculosis is a disease which is not easily diagnosable by conventional techniques like smear preparation and Mycobacterium cultures. Also it is present at inaccessible sites so biopsy also doesn’t remain a viable and safe procedure. Hence there is a need for a contemporary approach that is both sensitive as well as specific. With advancements in molecular biology techniques and genetic procedures like PCR and ELISA, EPTB can be hoped to be diagnosed sooner than the conventional gold standard smear and culture of Mycobacterium. But the problem is that these techniques empty the pockets of the common man and requires skilled technicians as well. Adenosine deaminase assay is a cost effect liquid stable test system that can be run either manually or on open automated chemistry systems. It is reported to have high sensitivity for the disease.