MS (Final Exam)

Question 1

this is an autoimmune disease of the central nervous system. it is characterized by
- chronic inflammation
- demyelination, gliosis (plaqures/scarring)
- neuronal loss
- can be relapsing or progressive

Answer 1

multiple sclerosis (MS)

Question 2

what does the chronic inflammation in MS target

Answer 2

myelin sheath

Question 3

how to gilal cells form plaques?

Answer 3

glial cells become astrocytes which proliferate and then harden and make plaques

Question 4

true or false: axons are usually spared in MS

Answer 4

true

Question 5

true or false: MS plaques typically develop at the same time in the same CNS locations

Answer 5

false - MS plaques typically develop at different times in different CNS locations

Question 6

does MS usually affect younger or older adults

Answer 6

younger < 40

Question 7

what are some risk factors for MS

Answer 7

• genetic predisposition
• vitamin D deficiency
• Esptein-Barr virus (EBV) exposure after early childhood
• cigarette smoking

Question 8

which gene has the strongest susceptibility for MS

Answer 8

HLA-DRB1 gene

Question 9

what are some other genes that may have susceptibility for MS

Answer 9

• IL-7 receptor (CD127)
• IL-2 receptor (CD25)
• T cell costimulatory molecule LFA-3 (CD58)

Question 10

do all genes lack sensitivity or specificity for MS?

Answer 10

both!

Question 11

does specificity or sensitivity lead to false positives

Answer 11

sensitivity

Question 12

do specificity or sensitivity lead to false negatives

Answer 12

specificity

Question 13

how does the cellular immunity cause inflammation in MS

Answer 13

• presence of perivenular T cells and macrophages (cuffing)
• infiltrate the surrounding white matter
• disrupt the blood brain barrier
• distinct from vasculitis

Question 14

how does the humeral immunity cause inflammation in MS

Answer 14

• small numbers of B lymphocytes infiltrate the nervous system
• presence myelin-specific autoantibodies on degenerating myelin sheaths
• complement also activated

Question 15

___________ is the pathological hallmark for MS

Answer 15

demyelination (damage to the myelin sheath)

Question 16

these show up on MRI when someone has MS because 1/2 of the cells are regenerated and the other half are not. when there is a lack of myelin, we see grey. therefore these are called

Answer 16

shadow plaques

Question 17

in MS, there is cerebral cortex involvement, which includes inflammation, demyelination and axonal loss. does the axonal loss start from distal to proximal or proximal to distal?

Answer 17

distal to proximal

Question 18

these resemble secondary lymphoid tissue
- aggregates of T and B lymphocytes
- proximity to plaques and perivascular spaces
- more common in progressive MS
- may contribute to subcortical demyelination and neurodegeneration

Answer 18

meningeal clusters

Question 19

what type of matter are meningeal clusters associated with

Answer 19

Pia matter

Question 20

________________ is always present during active demyelination or axonal injury and appears to differ between early and later stages

Answer 20

inflammation

Question 21

does this describe progressive or remission MS
- focal perivenular parenchymal infiltration of lymphocytes and monocytes
- BBB disruption and active demyelination

Answer 21

remission MS (RMS)

Question 22

does this describe progressive or remission MS
- more diffused with widespread microglial activation
- fewer acute perivascular infiltrates
- BBB not involved

Answer 22

progressive MS

Question 23

_________ occurs behind a partially repaired BBB

Answer 23

inflammation

Question 24

where are activated reactive t-cells present?

Answer 24

blood, CSF, MS lesions
myelin basic protein (MBP) antigen

Question 25

which t-cell populations are present in MS?

Answer 25

Th1, TNF-alpha and IGFN-gamma - activation/maintenance of autoimmune responses - direct injury to oligodendrocytes and myelin Th17 and IL17

Question 26

where are B cells present?

Answer 26

- myelin oligodendrocyte glycoprotein (MOG) - CSF

Question 27

these two factors are the main contributor to irreversible neurologic disability

Answer 27

- cumulative axonal loss - neuronal loss

Question 28

about 7-% of axons are lost from the lateral corticospinal motor tracts in patients with advanced ___________

Answer 28

paraparesis (partial loss of control)

Question 29

what are some things that may cause axonal and neuronal death

Answer 29

- glutamate-mediated excitotoxicity - oxidative jinjury - iron accumulation - mitochondrial failure

Question 30

explain how a nerve impulse is transmitted down an axon in a normal person vs someone with MS

Answer 30

normal: saltatory nerve impulse that jumps from one Node of Ranvier to the next. there are sodium channels at these nodes and is where depolarization occurs MS: demyelination has occurs and there are now increased sodium channels distributed along the axon, which causes continuous propagation of the nerve action potential despite the absence of myelin

Question 31

is the clinical presentation of MS usually abrupt or inscidious?

Answer 31

could be either!

Question 32

true or false: can go from mild to severe symptoms very quickly

Answer 32

true

Question 33

list some symptoms of MS

Answer 33

- sensory: parestesias (prickling), hypestesias, pain - optic neuritis: diminished visual acuity & color perception, periorbital pain - weakness of limbs: spasms, hyperreflexia, babinski sign - ataxia, vertigo - heat sensitivity - bladder dysfunction: detrusor hyperreflexia - constipation/bowel incontinence - cognitive dysfunction

Question 34

what are the three types of MS that exist

Answer 34

- relapsing MS - primary progressive MS - secondary progressive MS

Question 35

this type of MS is characterized by discrete attacks of neurologic dysfunction that generally evolve over days-weeks. with initial attacks, there is usually complete recovery. however, as attacks continue, recovery may be less evident

Answer 35

relapsing MS (RMS)

Question 36

this type of MS always begins as RMS. At some point, however, the clinical course changes so that the patient experiences progressive deterioration in function unassociated with acute attacks. this produces a greater amount of fixed neurologic disability than RMS.

Answer 36

secondary progressive MS (SPMS)

Question 37

this type of MS, patents do not experience attacks, but rather a steady decline in function from disease onset.

Answer 37

primary progressive MS (PPMS)

Question 38

how is MS diagnosed

Answer 38

clinically defined MS is: two or more episodes of symptoms and tow or more signs with radiographic evidence (MRI); symptoms must last 24 hours and occur as separate episodes a month or more apart.

Question 39

what may indicate a favourable prognosis for MS

Answer 39

- optic neuritis or sensory symptoms at onset - less than two relapses per year - minimal impairment after 5 years

Question 40

what may indicate a poor prognosis for MS

Answer 40

- truncal ataxia (affects trunk/back muscles which causes a hesitation when trying to produce movement - looks drunk) - action tremor (different from Parkinsons) - progressive disease course