Diagnostic value of serum adenosine deaminase level in pulmonary tuberculosis

BACKGROUND: In some studies, the level of adenosine deaminase (ADA) in sputum and effusion liquids was used for the diagnosis of tuberculosis (TB). But it is not always possible to access these materials. The goal of this study is to assess the diagnostic value of serum ADA levels in pulmonary TB patients. MATERIALS AND METHODS: In this study, 40 sputum smear-positive TB patients who were hospitalized and 40 non-TB patients who referred for surgeries were selected. A serum sample was collected and serum ADA level was measured by ADA kit. RESULTS: The average (SD) of serum ADA in TB and non-TB patients were 20.88 (±5.97) and 10.69 (±2.98) U/L, respectively (P value < 0.05). The best cut-off point was 14 U/L. The calculated area under the receiver operating characteristic (ROC) curve was 0.955 (95% CI, 0.914-0.995); sensitivity was 92.7% (95% CI, 84.7-100) and specificity was 88.1% (95% CI, 78.3-97.8) (P < 0.001). CONCLUSION: Serum ADA level may be proposed as a proper index for TB diagnosis.