Multiple Sclerosis

Question 1

Define:

Answer 1

Inflammatory demyleninating disease of the CNS - discrete plaques of demyleinating occur at multiple CNS sites from T-cell mediated immune response.

Question 2

Aetiology/risk factors:

Answer 2

UNKNOWN

Auto-immune basis with potential environmental trigger in genetically susceptible individuals

Leads to impaired axonal conduction

RF –>EBV exposure + prenatal vitamin D levels

Question 3

Epidemiology:

Answer 3

1/1000 = UK prevalence
2x as common in females
Age of presentation 20-40 years

Question 4

Symptoms:

Answer 4

Varies depending on the site of inflammation

Usually monosymptomatic

Question 5

Optic neuritis symptoms:

Answer 5

unilateral deterioration of visual acuity

Colour perception

Rapid loss of central vision

Question 6

Sensory symptoms:

Answer 6

Pins and needles

numbness

burning

Question 7

Motos symptoms:

Answer 7

Limb weakness

Spasms

Stiffness

heaviness

Question 8

Autonomic symptoms:

Answer 8

urinary urgency

hesitancy

incontinence

impotence

Question 9

Psychological symptoms:

Answer 9

depression

psychosis

amnesia

Question 10

Sexual symptoms:

Answer 10

Anorgasmia

Erectile dysfunction

Question 11

GI symptoms:

Answer 11

Swallowing disorders

Constipation

Question 12

Cerebellum signs:

Answer 12

Trunk and limb ataxia

Intention tremor

Scanning speech

Tinnitus

Question 13

Signs:

Answer 13

• Optic Neuritis

Central scotoma (if optic nerve is affected)
•	Scotoma = a blind spot in the normal visual field
o	Field defects (if optic radiations are affected)

Relative Afferent Pupillary Defect (RAPD)

Internuclear Ophthalmoplegia

• Sensory
o Paraesthesia

Motor
o UMN signs

Cerebellar
o	Limb ataxia (intention tremor, past-pointing, dysmetria)
o	Dysdiadochokinesia
o	Ataxic wide-based gait 
o	Scanning speech

Uhthoff’s Sign - worsening of neurological symptoms as the body gets overheated from hot weather, exercise, saunas, hot tubs etc.

Lhermitte’s Sign - an electrical sensation that runs down the back and into the limbs when the neck is flexed

Question 14

Investigations:

Answer 14

• Diagnosis is based on the finding of two or more CNS lesions with corresponding symptoms, separated in time and space - McDONALD CRITERIA

Lumbar Puncture
o Microscopy - exclude infection/inflammatory causes
o CSF electrophoresis shows unmatched oligoclonal bands

MRI Brain, Cervical and Thoracic Spine (with gadolinium) – shows lesions
o Plaques can be identified

• Evoked Potentials
o Visual, auditory and somatosensory evoked potentials may show delayed conduction velocity