Meningitis represents a dangerous medical condition which targets the protective
brain and spinal cord membranes known as meninges.Ultimately, regardless of the type of causative agent, the common outcome of this
inflammatory pathway is multifactorial neuronal damage.The surface of these microbes contains pathogenic molecules called PAMPs
(Pathogen-Associated Molecular Patterns) which activate specific immune receptors
called Toll-Like Receptors (TLRs) particularly TLR2 and TLR4 that exist on nervous
system cells and immune system cells.When the BBB is
disrupted, there is an increase in permeability of the BBB that allows for the outflow
of fluid and protein from the intravascular to the extravascular spaces surrounding
the brain parenchyma leading to cerebral edema.Following the release of these effector cells within the brain, they produce both
mediators and proinflammatory cytokines that induce vascular dilatation and
increase the permeability of the intracranial blood vessel, contributing to increased
ICP.The cerebrospinal fluid attracts leukocytes primarily neutrophils during meningitis
development.