Multiple Sclerosis

Question 1

What is MS?

Answer 1

Presumed autoimmune demyelinating disorder of the central nervous system

Question 2

What is the prevalence of MS?

Answer 2

Affects >400k people in the US, but is thought to be underestimated

Lifetime risk is 0.1- 0.2%

Question 3

What is Charcot’s Triad of MS?

Answer 3

Nystagmus, intention tremor and scanning speech

Question 4

Who is the stereotypical patient that gets MS?

Answer 4

younger females, 20-50 yrs old of northern european descent that live farther from the equator (lower vitamin D levels)

Females: Males is 2:1 or 3:1

Question 5

What is the genetic contribution to MS?

Answer 5

There is a genetic component -certain HLAs and SNPs increase risk- but it is not a genetic disease

Question 6

What three factors influence the onset of MS?

Answer 6

Genetics, germs, and geography

Question 7

What is the pattern of symptoms seen in MS?

Answer 7

The disease is characterized by clinical relapses (new neurological signs/symptoms lasting more than 24 hours) due to CNS demyelination followed by remission (complete or partial improvement of symptoms

Over time, patients develop progressive symptoms without clear clinical relapses or new lesions

Question 8

What are some optic syndromes highly suggestive of MS?

Answer 8

Optic neuritis (Decreased monocular vision, Often involving central vision,,Pain with eye movement
Decreased red/green color, Clinically associated with an afferent pupillary defect (APD or Marcus-Gunn pupil),Uhthoff phenomeon (heat intolerance) 
“Hot bath test”)

Question 9

What is a Marcus Gunn Pupil?

Answer 9

Afferent pupillary defect- Marcus Gunn pupil is a medical sign observed during the swinging-flashlight test whereupon the patient’s pupils constrict less (therefore appearing to dilate) when a bright light is swung from the unaffected eye to the affected eye. The affected eye still senses the light and produces pupillary sphincter constriction to some degree, albeit reduced.

Question 10

What are some brainstem syndromes highly associated with MS?

Answer 10

Internuclear ophthalmoplegia (MLF lesion)
Oculomotor dysfunction
Ataxia
Trigeminal Neuralgia
Facial nerve palsy
CST/upper motor neuron involvement

Question 11

What are some spinal cord syndromes associated with MS

Answer 11

Partial myelopathy
Lhermitte’s “sign” (electric shock sensation with the neck flexed)
Numbness/sensory level
Deafferented hand
Urinary urgency, incontinence, erectile dysfunction (do not occur with GBS—commonly misdiagnosed)
Progressive asymmetric spastic paraplegia

Question 12

How is MS diagnosed?

Answer 12

Diagnosis rests on the objective demonstration of CNS white matter lesions—based on clinical and radiographic grounds—that are disseminated in time & space for which there is no better alternative diagnosis

Question 13

What test confirms MS?

Answer 13

There is no single test that “confirms” MS—it is ultimately a clinical diagnosis with radiographic corroboration

Question 14

What are the four typical MS lesions seen on MRI?

Answer 14

Juxtacortical, periventricular, GdE, and infratentorial

Question 15

How large is a typical MS lesions?

Answer 15

< 3mm

Question 16

What characteristic lesions seen on MRI are pathognomonic for MS?

Answer 16

Dawson’s fingers

Question 17

Where do MS spinal cord lesions tend to appear?

Answer 17

Spinal cord lesions are usually small (< 1/2 vertebra), and located in the cord periphery, especially the dorsal columns.

Question 18

What is the white cell count in someone with MS?

Answer 18

Usually low- some patients experience a white count of up to 50 mm3

Question 19

How are CSF protein levels affected by MS?

Answer 19

rarely > 100/dL

High levels are associated with cord inflammation

Question 20

How is glucose affected by MS?

Answer 20

Glucose levels are normal

Question 21

What’s the role of oligoclonal bands in teh diagnosis of MS?

Answer 21

Not mandatory for diagnosis but highly tested…

increased oligoclonal bands. Lots of disease processes lead to an increase in oligoclonal bands though..

Question 22

how is IgG affected by MS/

Answer 22

IgG levels are elevated

Question 23

What are some ddx’s for MS?

Answer 23

Neuromyelitis Optica, Acute disseminated Encephalomyelopathy (ADEM), Progressive multifocal Leukoencephalopathy (PML)

Question 24

What clinical features help differentiate MS from neuromyelitis optica?

Answer 24

MS has unilateral optic neuritis

NMO has bilateral optic neurities

Question 25

What lesions are seen on imaging for NMO (neuromyelitis optica)

Answer 25

Longitudinally extensive spinal cord lesions. with normal or minimal brain lesions

Question 26

WHat is acute disseminated encephalitis (ADEM)?

Answer 26

Think of it as a bad, one time experience of MS.

Often a post-infectious process that commonly presents with HA, vomiting, dizziness, and meningism. Affects kids more than adults.

Question 27

How do ADEM lesions appear on MRI?

Answer 27

Large, “fluffy” multifocal lesions

Question 28

What is the cause of progressive multifocal leukoencephalopathy?

Answer 28

PMl is caused by opportunistic infections such as the JC virus. It is commonly seen in patients with HIV (often a presenting symptom)

Can lead to death or severe neurologic injury

Question 29

PML can be a rare side effect of what?

Answer 29

Taking the drug natalizumab (for MS) in people who are also JC virus positive

Question 30

What is the primary goal in treatment of MS?

Answer 30

Reduce the rate of relapse –> make life as “normal” as possible

Question 31

What are very important considerations when choosing treatment for someone with MS?

Answer 31

-Side effect profile
Long term safety profile
Will the patient take the medicine?

Question 32

What is the preferred tx for a relapse in MS?

Answer 32

IV steroids, (also oral prednisone, but IV steroids on exam)
ACTH
Plasmapharesis
IVIG

Question 33

What is the most important tool for diagnosing MS?

Answer 33

Clinical suspicion. MRI corroborates, but clinical suspicion is the most important.