Induced hypothermia in experimental pneumococcal meningitis

Pneumococcal meningitis resulting from Streptococcus pneumoniae has a death rate of 28% in adults. In severe bead injury and stroke, inflammatory chan ges and intracranial hypertension are improved by induced hypothermia, whic h also is neuroprotective. We hypothesized that moderate hypother- mia amel iorates inflammatory changes in experimental pneumococcal meningitis. Wista r rats were cooled systemically, and meningitis was induced by pneumococcal cell wall components. The increase of regional cerebral blood flow in the meningitis animals was blocked by hypothermia at 6 hours. The reduction of intracranial pressure correlated with temperature. The influx of leukocytes into the cerebrospinal fluid and levels of tumor necrosis factor alpha in the cerebrospinal fluid were decreased. Cooling the animals 2 hours after m eningitis induction to 30.5 degrees C was also protective. We conclude that hypothermia is a new adjuvant approach to reduce meningitis-induced change s, in particular intracranial pressure, in the early phase of the disease.