what is multiple sclerosis

Question 1

what is MS?

Answer 1

autoimmune demyelination of neurones in the central nervous system

Question 2

what are the causes of MS?

Answer 2

Multiple genes
Epstein–Barr virus (EBV)
Low vitamin D
Smoking
Obesity

Question 3

what is the most common presentation of MS?

Answer 3

optic neuritis, which involves demyelination of the optic nerve of one eye

Question 4

who is mostly affected by MS?

Answer 4

• young adults <50
• more common in women
• usually better in pregnancy

Question 5

how long do MS episodes last?

Answer 5

• days to weeks

Question 6

what are the different categories of MS?

Answer 6

Relapsing-remitting:
The most common pattern (85% of cases)
Episodic flare-ups (may last days, weeks or months), separated by periods of remission
60% of patients develop secondary progressive MS within 15 years

Secondary progressive:
Initially, the disease starts with a relapsing-remitting course, but then symptoms get progressively worse with no periods of remission
Associated with co-ordination difficulties and bladder/bowel issues

Primary progressive:
Symptoms get progressively worse from disease onset with no periods of remission
Accounts for 10% of cases and is more common in older patients

Question 7

which investigations can you do for MS?

Answer 7

• MRI scans can demonstrate typical lesions- shows demyelinating plaques. paraventricular plaques can also be found perpendicular to the ventricles and these are called Dawsons fingers- new lesions will show up enhanced and old ones will not. this can demonstrate dissemination of symptoms in time and space
• Lumbar puncture can detect “oligoclonal bands” in the cerebrospinal fluid (CSF)

Question 8

how does optic neuritis present?

Answer 8

Central scotoma. This is an enlarged blind spot.
Pain on eye movement
Impaired colour vision
Relative afferent pupillary defect

Question 9

what is the management of optic neuritis?

Answer 9

Patients presenting with acute loss of vision should be seen urgently by an ophthalmologist for assessment. It is treated with steroids and recovery takes 2-6 weeks.

Question 10

what is the prognosis for someone presenting with optic neuritis?

Answer 10

Around 50% of patients with a single episode of optic neuritis will go on to develop MS over the next 15 years. Changes on an MRI scan help to predict which patients will go on to develop MS.

Question 11

what is the management of MS?

Answer 11

DMARDs and biologics to induce remission

Question 12

what additional treatments can be given for MS?

Answer 12

• Exercise to maintain activity and strength
• Neuropathic pain can be managed with medication such as amitriptyline or gabapentin
• Depression can be managed with antidepressants such as SSRIs
• Urge incontinence can be managed with anticholinergic medications such as tolterodine or oxybutynin (although be aware these can cause or worsen cognitive impairment)
• Spasticity can be managed with baclofen, gabapentin and physiotherapy

Question 13

which presentations occur commonly in MS?

Answer 13

• numbness and tingling
• weakness and sensory loss
• bowel and bladder symptoms with upper motor neurone signs
• uhtoffs phenomenon- symptoms are worse when hot or taking a bath
• lehermittes- electric shock sensation on neck flexion

Question 14

what is an example of what may happen if there is internuclear ophthalmoplegia?

Answer 14

inability of right eye to adduct when looking left

Question 15

what is the McDonald criteria?

Answer 15

the diagnostic criteria for MS

symptoms/signs which demonstrate dissemination in space (i.e. different parts of the CNS affected) and time.

2 or more relapses AND EITHER
Objective clinical evidence of 2 or more lesions OR
Objective clinical evidence of one lesion WITH a reasonable history of a previous relapse
‘Objective evidence’ is defined as an abnormality on neurological exam, MRI or visual evoked potentials [5]