Diagnostic Value of Serum Adenosine Deaminase Level in Extrapulmonary Tuberculosis

Background: Although tuberculosis is a known disease, still on occasion, the tuberculosis patients remain undiagnosed and hence not treated appropriately. In some cases, the patient is not able to give a proper sputum sample. In some other cases, expert laboratory technician to examine the patient’s sputum smear is not available. Furthermore, and in most cases of extrapulmonary tuberculosis, invasive diagnostic procedures such as biopsy might be followed. The aim of this study was to investigate the diagnostic value of serum level of adenosine deaminase (ADA) in extra pulmonary tuberculosis. Methods: In this analytical study, pulmonary tuberculosis patients were compared with two other groups of patients including lung cancer patients and healthy controls, based on national tuberculosis protocol. In each group, ۴۰ patients who almost matched for age and sex were included. Blood samples were taken from the participants to measure serum ADA levels. Data were analyzed using SPSS software version ۱۵.۰. Results: Based on the data analyzed in this study, the mean ADA level in the patients with extra pulmonary tuberculosis was ۲۳.۸ IU/L which was significantly higher than that in the other groups (P<۰.۰۰۱). Mean ADA levels in lung cancer patients and in healthy subjects were ۱۵.۸ IU/L and ۱۰.۷ IU/L, respectively. Conclusions: According to the results of this study, higher cut-off value for ADA would increase the specificity up to ۱۰۰%. Moreover, serum ADA level can be a valuable additional index in diagnosis of extra pulmonary tuberculosis.