1b// Cerebral inflammation & disorders

Question 1

what is meningitis?

Answer 1

inflammation of the meninges caused by viral or bacterial infection

Question 2

what is encephalitis?

Answer 2

inflammation of the brain caused by infection or autoimmune mechanisms

Question 3

what is cerebral vasculitis?

Answer 3

inflammation of blood vessel walls

aka angiitis

Question 4

What led to the suggestion fothe blood brain barrier?

Answer 4

Question 5

How would you desribe the vascularisation of the CNS?

Answer 5

dense, no neurton is more than 100 micro m from a capillary

Question 6

What do BBB capillaries have?

Answer 6

BBB capillaries have extensive tight junctions at the endothelial cell-cell contacts, massively reducing solute and fluid leak across the capillary wall

Question 7

what does the histology of meningitis look like?

Answer 7

infiltration of subarachnoid space by WBCs, pussy exudate

Question 8

what does the histology of viral encephalitis look like?

Answer 8

perivascular cuffing

Question 9

how vascularised is the brain?

Answer 9

no neuron is more than 100micrometers from a capillary

Question 10

how does the BBB form?

Answer 10

BBB capillaries have extensive tight junctions at endothelial cell-cell contacts, nothing can freely diffuse

Question 11

what happens if the BBB is broken?

Answer 11

blood leaks into brain, astrocytes attempt to clear blood borne products by retracting end feet (leaving BBB undefended)

Question 12

what may happen long term if the BBB is chronically disrupted?

Answer 12

fibrosis in brain vessels, small vessel disease

Question 13

what are the initial symptoms of encephalitis?

Answer 13

flu like with pyrexia and headache

Question 14

what are the overall symptoms of encephalitis? (7)

Answer 14

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

Question 15

what are the viral causes of encephalitis? (4)

Answer 15

herpex simplex
measles
varicella
rubella

Question 16

what are the non-viral causes of encephalitis?

Answer 16

mosquito/insect bites
bacterial or fungal infections - untreated meningitis
trauma
autoimmune

Question 17

how is encephalitis treated?

Answer 17

depends on underlying cause:
antivirals/antibiotics/antifungals
steroids
analgesics
anti-convulsants (often prophylactically)
ventilation

Question 18

what is multiple sclerosis?

Answer 18

demyelinating autoimmune disease of the CNS

relapsing and remitting - 1st resolves spontaneously

Question 19

What is relapse and progression of multiple sclerosis linked to?

Answer 19

relapse= inflammatory activity
progression= neurodegeneration

Question 20

what is the cellular pathology of multiple sclerosis?

Answer 20

inflammation
demyelination & axonal loss (larger grey areas)
neurodegeneration

Question 21

Why do symptoms vary in multiple sclerosis?

Answer 21

Symptoms vary because the amount and location of damage to the nervous system is different in each person with MS

Question 22

What happens during inflammation in multiple slcerosis?

Answer 22

perivascular immune cell infiltration (CD3 T cell and CD20 B cells)

Question 23

What is meningitis?

Answer 23

Irritation, inflammation and swelling of the meninges

6th most common infectious disease killer
Leaves 1 in 5 of the infected people with an
impairment

Question 24

what are the bacterial causes of meningitis?

Answer 24

meningococcal (most common)
pneumococcal
haemophilus influenzae type B
streptococcal (main cause in newborns)

Question 25

what are the causes of meningitis?

Answer 25

bacteria viruses (rarely life threatening) fungi

Question 26

how is meningitis diagnosed?

Answer 26

lumbar puncture for CSF sample

Question 27

what are the hallmarks of meningitis?

Answer 27

sudden onset of fever, headache, nausea, double vision, photophobia, stiff neck, rash

Question 28

what are some long term effects of meningitis? (7)

Answer 28

``` disabilities memory loss coordination loss behaviour changes paralysis/weakness speech coord issues visual defects ```

Question 29

what diagnostic tests are useful for suspected encephalitis or meningitis?

Answer 29

lumbar puncture - raised WCC, pink colour low csf glucose in bacterial men CT/MRI neurological assessment

Question 30

What is an infection of the spinal cord known as?

Answer 30

myelitis

Question 31

What types of infections can cause encephalitis and meningitis?

Answer 31

Encephalitis: more commonly viruses (e.g. Herpes Simplex, measles, varicella (chickenpox), rubella (German measles). Meningitis: more commonly bacteria which initially cause an upper respiratory tract infection and then travel through the blood to the brain. Types of meningitis include (most serious is pneumococcal - streptococcus pneumoniae; meningococcal - Neisseria meningitides; Haemophilus influenzae meningitis caused by Haemophilus influenzae b– reduced by Hib vaccination, previously a leading cause in children under 5).

Question 32

What are some hallmarks of encephalitis and meningitis?

Answer 32

Encephalitis: fever, seizures, change in behaviour, and confusion and disorientation. Meningitis: sudden fever, severe headache, nausea or vomiting, double vision, drowsiness, sensitivity to bright light, and a stiff neck, rash (not always).

Question 33

What diagnostic tests can be performed for encephaltiis, meningits and multiple sclerosis?

Answer 33

Neurological examination, CT, MRI, lumbar puncture (CSF is usually clear and colourless; low glucose in bacterial meningitis; raised white blood cell counts are a sign of inflammation), blood, urine analysis.

Question 34

What are some of the long term effects of meningitis?

Answer 34

**Long term learning disabilities, memory loss, poor concentration, clumsiness/co-ordination problems, headaches, deafness/hearing problems/tinnitus/dizziness/loss of balance, epilepsy, weakness/paralysis/spasms, speech problems, visual problems. **