Invasion of the Central Nervous System by Neisseria meningitidis

Abstract : Neisseria meningitidis is an extracellular pathogen responsible for septicemia and meningitis. The occurrence of meningitis requires that bacteria cross the blood-brain barrier (BBB) and induce an inflammatory response within the sub arachnoid space. The mechanisms that lead to the development of cerebrospinal fluid (CSF) pleocytosis once bacteria have reached the CSF have been studied using several animal models. These mechanisms are similar among extracellular pathogens responsible for meningitis (i.e., Haemophilus influenzae type b, Streptococcuspneumoniae, and N. meningitidis). The in situ production of cytokines is the primary event leading to transmigration of leucocytes through the BBB (1-4).