Brain Acidosis in Experimental Pneumococcal Meningitis

Abstract
Purulent meningitis is a serious disease that often has a lethal outcome or gives lasting complications due to brain damage. The processes causing brain dysfunction or damage are still not uncovered nor are the reasons for the characteristic increase of CSF lactate, or the decrease of glucose levels and of pH. We studied rabbits with experimentally induced purulent meningitis (Streptococcus pneumoniae). Ten hours after the inoculation into cisterna magna the rabbits developed symptoms of meningitis, with stiffness of the neck, tachypnea, and fever. The CSF level of lactate and the number of leukocytes were significantly increased and the glucose level was decreased. Brain interstitial pH, as measured by ion selective microelectrodes, was significantly decreased from the normal level of 7.4 to 6.9. The levels of energy metabolites in brain cortex, including glucose, were not different between controls and infected animals, and the lactate level was not elevated more than could have been explained by passiv...