β-glucuronidase in the diagnosis of bacterial meningitis and response to treatment

Aim: beta-Glucuronidase activity is increased in the cerebrospinal fluid (CSF) of patients with bacterial meningitis. The aim of this study was to investigate the beta-glucuronidase activity in the cell-free CSF of bacterial meningitis and its course during treatment, and compare it with other CSF parameters. Methods: The beta-glucuronidase activity, cell number, protein concentration and CSF/blood glucose ratio were measured in 43 consecutive infants and children with bacterial meningitis, and 97 control subjects. Patients had one or two follow-up lumbar punctures. Results: The beta-glucuronidase activity was increased early in bacterial meningitis, even when the other CSF parameters were undisturbed. Before treatment, the median activity in affected children was 136 mumoles 4-methylumbelliferone l(-1) h(-1) (range 44-826) and in controls 14 (7-23). In all patients who improved, the activity was lower in the follow-up CSF samples. Six to 12 h after starting treatment, the median activity was already reduced by 59%. The other CSF parameters showed a variability during the first 24 h of treatment independently of the course of the disease. Multiple comparisons of the CSF parameters in 17 patients who had two follow-up punctures showed that the beta-glucuronidase activity was the best prognostic index. Conclusion: beta-Glucuronidase activity in the CSF is a reliable indicator of bacterial meningitis, which can identify the response to treatment early in the course of illness. The enzyme activity is increased early in the disease, even when the other laboratory parameters from the CSF remain normal.