CEREBROSPINAL-FLUID ADENOSINE-DEAMINASE ACTIVITY FOR THE DIAGNOSIS OFTUBERCULOUS MENINGITIS IN CHILDREN

Adenosine deaminase (ADA) activity was measured in the cerebrospinal f luid (CSF) of 27 subjects suffering from tuberculous meningitis (TBM), 19 from bacterial meningitis, 10 from encephalitis, and 10 control su bjects. The mean CSF ADA level was significantly raised (P<0.001) in T BM patients as compared to other study groups. A cut-off CSF ADA level of >5 IU/l was considered for the diagnosis of TBM, and the test had sensitivity and specificity of 89 and 92 per cent, respectively, Overa ll, it was found to be a better test in comparison to any other single test for the diagnosis of TBM. Confirmed TBM patients had significant ly higher CSF ADA activity when compared with clinical TBM (P<0.01) an d the levels did not differ significantly among different stages of di sease, The ADA level in TBM cases had significant correlation with CSF cell count (P<0.01), lymphocyte percentage (P<0.02) and protein conce ntration (P<0.02), Thus, the CSF ADA activity assay was found to be a simple, useful and rapid diagnostic test for the early recognition of TBM in children.