Adenosine deaminase, an aid in the diagnosis of tubercular meningitis – hospital based study

Abstract

Introduction: Tubercular meningitis (TBM) is the most prevalent and most grave form of extrapulmonary tuberculosis. It is associated with high mortality rate. The confounding factor for this is the delay in diagnosing the disease and initiation of treatment. The present study aims to look for the diagnostic utility of ADA estimations in Tubercular meningitis patients. Materials and Methods: For this study the patients with the signs and symptoms of meningitis and attending our hospital within a st ipulated period of one year approximately, were taken as subjects. As per the accepted criteria, the patients were segregated into two broad groups: tubercular meningitis cases and nontubercular meningitis cases. CSF specimens were collected and ADA levels were estimated on semiautoanalyser in the laboratory. Results: Out of 31 patients of tubercular meningitis, 27 showed ADA levels above 10 U/L while 2 showed lower values. On the other hand 32 cases of non- tubercular meningitis showed ADA levels below 10 U/L and 4 showed higher values, thereby supporting the fact that ADA evaluation in CSF is of substantial value in diagnosing TBM. It also illustrious that if CSF ADA value of 10 U/L is taken as bench mark then the sensitivity for diagnosing TBM is 93.10% and specificity is 88.87% which is fairly good. Conclusion: Therefore, just by evaluating CSF ADA levels we can diagnose the TBM cases with respectably good sensitivity and high specificity and consuming least time and resources. Therefore, ADA estimation is a valuable adjunct to routine investigations in diagnosis of TBM. Keywords: Tubercular Meningitis (TBM), Cerebrospinal fluid (CSF), Adenosine Deaminase (ADA).