Cerebrospinal fluid adenosine deaminase activity and C-reactive protein in tuberculous and partially treated bacterial meningitis.

Adenosine deaminase (ADA) activity measurement and C-reactive protein (C-RP) detection were done in CSF of 27 tuberculous meningitis (TBM) and 8 patients of partially treated bacterial meningitis, apart from routine biochemical tests. Both the groups had comparable CSF cell count, protein and sugar concentrations. The mean CSF ADA activity was significantly raised in TBM as compared to partially treated bacterial meningitis patients (p < 0.05). A cut-off ADA level < or = 5 IU/L and C-RP positively were used for differentiation of partially treated bacterial from TBM cases. Based on this, the sensitivity and specificity of ADA and C-RP were 62.5%, 88.9% and 75%, 100%, respectively. Since both the tests are simple and take lesser time to perform, they can be used as rapid diagnostic tests to remove diagnostic dilemma between the two diseases.