Comparative analysis of cerebrospinal fluid adenosine deaminase in tuberculous and non-tuberculous meningitis.

Objective: To calculate cut-off point for the adenosine deaminase (ADA) activity in the CSF of patients with tuberculous meningitis (TBM).

Patients And Methods: The ADA assay was based on the automatic indirect method in which ADA catalyzes adenosine to inosine. ADA activity in the CSF was calculated based on ammonia liberated from adenosine and quantified spectrophotometrically.