Neurotrophin-3 levels in cerebrospinal fluid from children with bacterial meningitis, viral meningitis, or encephalitis.

Neurotrophin-3 levels were measured in the cerebrospinal fluid of 35 patients with bacterial meningitis, viral meningitis, or encephalitis by two-site enzyme immunoassay. Elevated cerebrospinal fluid levels of neurotrophin-3 were demonstrated in 8 of 18 patients with bacterial meningitis. Follow-up examination of the eight patients at the convalescent stage showed diminished cerebrospinal fluid levels of neurotrophin-3. In contrast, none of the 17 patients with viral meningitis or encephalitis showed an elevation of neurotrophin-3 levels in cerebrospinal fluid. No relationships were observed between neurotrophin-3 levels and cerebrospinal fluid cell numbers, cerebrospinal fluid protein levels, serum C-reactive protein concentrations, or outcome in bacterial meningitis. Since neurotrophin-3 is involved in the survival of neurons and the modulation of the immune system, neurotrophin-3 could play a neuroprotective or immunomodulatory role in bacterial meningitis.