الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 185 |  |  |
| | | from | 185 | | |
Abstract
Meningitis describes inflammation of the membranes (meninges) and
/ or CSF that surround and protect the brain and spinal cord. Meningitis can
result from many causes, both infectious and non-infectious.
Meningitis is associated with high mortality rates and constitute
medical emergencies. Bacterial meningitis is a life-threatening condition
that requires prompt recognition and treatment. In adults, Neisseria
meningitides, Streptococcus pneumonia, and Haemophilus influenza are the
most common causes of bacterial meningitis whereas other agents are
incriminated in newborn such as group B Streptococcus, Escherichia coli
and Listeria monocytogenes. In bacterial meningitis, the prompt
administration of antibiotics is essential to the survival and recovery of the
patient.
Since antibiotics are ineffective in viral forms, the differential
diagnosis between bacterial and viral meningitis is a priority for making
optimal treatment choices. Clinical features are often insufficient to
discriminate the probable cause, and standard laboratory investigations
identify the causative agent in <60% of cases.
Traditional culturing methods can take several days to render results,
and an etiologic bacterial organism is identified in less than one-third of the
cases. Thus, rapid and accurate identification of the expected cause of the
infection is essential to initiate appropriate therapy and improve patient
outcome.
In such circumstances, identifying the association of biomarkers in
blood that best predict the etiology of meningitis (either bacterial or viral)
can provide timely clues regarding neuronal damage as well as any bacterial
culprits which antimicrobial therapy could neutralize.
S100B is a protein present in high concentrations in astrocytes cells in
the CNS; a release of S100B by these cells may represent glial response to
inflammation, ischemia, and metabolic stress. A high systemic inflammatory
burden, such as cases where patients are critically ill, predisposes patients to
extravasation of leukocytes across the blood–brain barrier and into the CNS
parenchyma. Astrocytes are a key component of the blood–brain barrier and
their interaction with the cerebrovascular endothelium defines the integrity
of the barrier. Thus, an interruption of the blood–brain barrier secondary to
inflammation may result in a communication between leukocytes and
astrocytes, leading to subsequent activation of astrocytes, with release of
S100B.
NSE is a well-established biomarker of neuronal stress, and it has
prognostic value for a range of neurological disorders. High NSE is a clear
indicator of several neurodegenerative conditions, including Friedreich
ataxia, hereditary spastic paraplegia, rare forms of Parkinson’s disease, and
Alzheimer’s disease. Increased levels of NSE have been significantly
correlated with stroke, certain types of cancer, and brain lesions following
heart surgery and cerebral infarction.