Relationship Between Age and Pleural Fluid Adenosine Deaminase Activity in Patients with Tuberculous Pleural Effusion

Abstract

Background : ADA is an enzyme found in most cells, and is involved in purine metabolism, but its chief role concerns the proliferation and differentiation of lymphocytes, especially T-lymphocytes. For that reason ADA has been looked on as a marker of cell-mediate immunity, which is the key mechanism of the tuberculous pleural effusion. Thus, the pleural fluid ADA activity is increased in the tuberculous pleural effusion. Age associated immune decline is characterized by decreases in both B and T-lymphocyte function and the former may be largely a result of the latter. Therefore, the pleural fluid ADA activity would be lower in old rather than in young, patients with tuberculous pleural effusion. We studied the relationship between age, and pleural fluid ADA activity, in patients with tuberculous pleural effusion. Materials and Methods : In the 46 patients with tuberculous pleural effusion enroll in this study, the pleural fluid ADA activities were measured by means of an automated kinetic method. Results : The mean age of the patients was years, with a male to female ratio of 30:16. The patients were divided into two groups, young patients, regarded as years with 28 and 18 patients, respectively. The pleural fluid ADA activity in both groups show significant differences : IU/L(young patients) Vs. IU/L(old patients)(p