Three recent studies found that corticosteroids improve clinical outcome and mortality in tuberculous meningitis (TBM), although the exact mechanism of action of the drug remains speculative. A number of reports on the effect of corticosteroids on cerebrospinal fluid (CSF) findings in TBM have been published, often with conflicting results regarding serial cell counts and protein levels. As part of a controlled, randomized trial on the effect of oral prednisone on outcome in childhood TBM at our institution, CSF was collected and analysed weekly during the 1st month of treatment. We found no significant difference in serial CSF cell counts between the steroid and non-steroid groups in the study. However, the steroid group had significantly lower CSF protein and globulin levels after the 1st month of treatment, and a more steady rise in CSF glucose levels than the non-steroid group. Knowledge of the different CSF responses during the course of anti-tuberculosis therapy is important in clinical decision-making.