1b// Cerebral inflammation & disorders Flashcards
what is meningitis?
inflammation of the meninges caused by viral or bacterial infection
what is encephalitis?
inflammation of the brain caused by infection or autoimmune mechanisms
what is cerebral vasculitis?
inflammation of blood vessel walls
aka angiitis
What led to the suggestion fothe blood brain barrier?
How would you desribe the vascularisation of the CNS?
dense, no neurton is more than 100 micro m from a capillary
What do BBB capillaries have?
BBB capillaries have extensive tight junctions at the endothelial cell-cell contacts, massively reducing solute and fluid leak across the capillary wall
what does the histology of meningitis look like?
infiltration of subarachnoid space by WBCs, pussy exudate
what does the histology of viral encephalitis look like?
perivascular cuffing
how vascularised is the brain?
no neuron is more than 100micrometers from a capillary
how does the BBB form?
BBB capillaries have extensive tight junctions at endothelial cell-cell contacts, nothing can freely diffuse
what happens if the BBB is broken?
blood leaks into brain, astrocytes attempt to clear blood borne products by retracting end feet (leaving BBB undefended)
what may happen long term if the BBB is chronically disrupted?
fibrosis in brain vessels, small vessel disease
what are the initial symptoms of encephalitis?
flu like with pyrexia and headache
what are the overall symptoms of encephalitis? (7)
confusion/disorientation seizures or fits depending on lobe affected: changes in personality/behaviour difficulty speaking weakness or loss of movement loss of consciousness catatonicity
within hours, days or weeks
what are the viral causes of encephalitis? (4)
herpex simplex
measles
varicella
rubella
what are the non-viral causes of encephalitis?
mosquito/insect bites
bacterial or fungal infections - untreated meningitis
trauma
autoimmune
how is encephalitis treated?
depends on underlying cause: antivirals/antibiotics/antifungals steroids analgesics anti-convulsants (often prophylactically) ventilation
what is multiple sclerosis?
demyelinating autoimmune disease of the CNS
relapsing and remitting - 1st resolves spontaneously
What is relapse and progression of multiple sclerosis linked to?
relapse= inflammatory activity
progression= neurodegeneration
what is the cellular pathology of multiple sclerosis?
inflammation
demyelination & axonal loss (larger grey areas)
neurodegeneration
Why do symptoms vary in multiple sclerosis?
Symptoms vary because the amount and location of damage to the nervous system is different in each person with MS
What happens during inflammation in multiple slcerosis?
perivascular immune cell infiltration (CD3 T cell and CD20 B cells)
What is meningitis?
Irritation, inflammation and swelling of the meninges
6th most common infectious disease killer
Leaves 1 in 5 of the infected people with an
impairment
what are the bacterial causes of meningitis?
meningococcal (most common)
pneumococcal
haemophilus influenzae type B
streptococcal (main cause in newborns)