MS

Question 1

What is the allele for the genetic predisposition and how much higher of a risk do they have?

Answer 1

HLA-DRB1501 MHC class 2 allele
3X higher risk for MS

Question 2

What do the majority of patients present with?

Answer 2

85%: Relapsing remitting symptoms (RRMS). Remainder 15% present with progressive relapsing or primary progressive MS.

Question 3

What are the signs and symptoms of MS (there are 9)

Answer 3

Focal weakness:
-UMN pattern of weakness

Focal numbness/paresthesias:
-Tingling, band like sensation around abdomen

Optic neuritis
-Painful inflammation of the optic nerve

Speech difficulties:

Lhermitte’s:
-Flexion of the neck results in parasthesiae (cervical cord demyelination)–>electrical sensation that runs down the back and into the limbs

Uhthoff’s:
-Symptoms exacerbated by overheating, reduces conduction due to lack of myelin

Coordination/gait/balance:

Spasticity:
-Esp in legs

Urinary symptoms:

Question 4

Gadolinium

Answer 4

Does not cross the BBB. If you have a gadolinium enhancing lesion, that means your BBB is breaking down. MS lesions do not respect vascular territory

Question 5

How is the BBB disrupted in MS

Answer 5

Perivascular inflammatory infiltration (T cells=driving force) secrete cytokines which disrupt capillary barriers

Question 6

MRI findings in MS (there are 6)

Answer 6

Gadolinium-enhancing lesion

• Frequent in subclinical phase
• Usually resolve

White matter lesion

• Myelin loss
• Often in corpus callosum in MS

Black holes

• Glial scar from myelin loss (SPMS correlation)
• Chronic MS lesions

Dawson’s fingers
-Seen on FLAIR image. Periventricular demyelination

Brain atrophy
-Occurs early and progresses

Spinal cord lesion
-Sensory complaints, loss of upper coordination, ambulatory difficulties

Question 7

Oligoclonal bands

Answer 7

IgG bands in the CSF, non specific for MS, but 80-90% of MS pts will have it

Question 8

MS treatments

Answer 8

1. Treat or remove inciting agents of stimulus
   - stress, infection
2. Mild
   - observe, reassurance, treat symptoms
3. Moderate/Severe
   - IV steroids, PT, treat symptoms

Everyone should always be on a treatment, stops progression

• Type I intereferon (Avonex, Rebif, Betaseron)
• Glatiramer acetate (copaxone)

Question 9

What are the key steps in MS neurophatogenesis

Answer 9

1. CNS entry of activated T cells, monocytes
2. Neuroinflammation
3. Axonal degeneration

Question 10

What are the classic clinical features of MS

Answer 10

Waxing and waning long tract signs occurring over weeks/months (motor, sensory, coordination etc)