Utility of Sputum Adenosine Deaminase in Tuberculosis Diagnosis: A Cost-Effective and Accessible Tool

Introduction: Tuberculosis (TB) remains one of the deadliest communicable diseases globally, with nearly 9 million new cases reported annually. The limitations of conventional and molecular diagnostic methods pose significant challenges in timely diagnosis and management. Sputum Adenosine Deaminase (ADA) is a rapid and accessible diagnostic tool for pulmonary tuberculosis. Objective: In this study, we aim to see the validity of sputum ADA levels in diagnosing pulmonary tuberculosis. Methodology: 95 participants were included in the study, including 45 patients with culture-confirmed pulmonary tuberculosis and 50 individuals without tuberculosis (culture-negative controls). ADA levels were measured in all sputum samples. The diagnostic accuracy of sputum ADA was calculated by using sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Results: A statistically significant difference in sputum ADA levels was observed between tuberculosis and non-tuberculosis patients (p = 0.001). At a cutoff value of 150 U/L, the sensitivity, specificity, PPV, and NPV were 82%, 76%, 75%, and 83%, respectively. Conclusion: The findings of this study support the utility of sputum ADA measurement as a rapid and reliable diagnostic tool for pulmonary tuberculosis. Its implementation could aid in the timely diagnosis and management of TB, particularly in regions with high disease prevalence.