Multiple Sclerosis

What is multiple sclerosis (MS)?

A chronic autoimmune demyelinating disease of the CNS characterized by episodes of neurologic dysfunction separated in time and space.

What causes MS?

Immune‑mediated destruction of CNS myelin and axons leading to demyelinating plaques and progressive neurologic impairment.

What age group is most commonly affected by MS?

Young adults aged 20–40 years.

What epidemiologic features are associated with MS?

• Female predominance

• Higher prevalence in temperate climates

• Young adult onset

What are major risk factors for MS?

• Smoking

• EBV exposure

• Low vitamin D

• Genetic predisposition

• Female sex

• Temperate climate residence

What is the underlying pathophysiology of MS?

T‑cell mediated autoimmune attack on CNS myelin causing inflammation, demyelination, axonal loss, and formation of plaques disseminated in time and space.

What symptoms commonly occur in MS?

• Optic neuritis

• Weakness/numbness

• Heat intolerance (Uhthoff phenomenon)

• Sensory loss

• Fatigue

• Bladder dysfunction

• Diplopia

• Lhermitte’s sign

• Ataxia

What is optic neuritis?

Inflammation of the optic nerve causing painful vision loss, afferent pupillary defect, and optic disc edema.

What is Uhthoff’s phenomenon?

Worsening of MS symptoms with heat exposure.

What is Lhermitte’s sign?

Electric shock sensation down the spine/legs triggered by neck flexion.

What physical exam findings are typical in MS?

• Afferent pupillary defect

• Optic disc edema

• Weakness

• Hyperreflexia

• Sensory deficits

What neurologic finding is highly suggestive of MS?

Internuclear ophthalmoplegia due to MLF demyelination.

What laboratory tests are used in the evaluation of MS?

• CBC

• BMP

• ESR/CRP

• B12

• AMA

• HIV

• TSH w/ fT4

• Lyme titers

What imaging study is most sensitive for diagnosing MS?

MRI of the brain with gadolinium contrast.

What MRI findings are characteristic of MS?

• Multiple hyperintense white matter plaques

• Periventricular “Dawson’s fingers”

• Juxtacortical, infratentorial, or spinal cord lesions

What CSF finding supports the diagnosis of MS?

Oligoclonal bands indicating intrathecal IgG production.

What diagnostic criteria are used for MS?

• Dissemination in space

• Dissemination in time

• Typical MRI lesions

• Oligoclonal bands on LP

What does “dissemination in space” mean in MS?

Lesions in ≥2 distinct CNS regions (periventricular, juxtacortical, infratentorial, spinal cord).

What does “dissemination in time” mean in MS?

New lesions on follow‑up MRI or multiple clinical episodes separated in time.

What are the primary treatment goals in MS?

• Treat acute relapses

• Slow disease progression

• Reduce relapse frequency

• Manage symptoms

What is first‑line treatment for acute MS exacerbations?

IV high‑dose glucocorticoids

What treatment is used for severe MS relapses unresponsive to steroids?

Plasmapheresis

What medications are used as disease‑modifying therapy in MS?

• Interferon beta

• Glatiramer acetate

• Dimethyl fumarate/diroximel fumarate

• Monoclonal antibodies (e.g., natalizumab, ocrelizumab)

What symptomatic treatments are used in MS?

• PT

• Amantadine for fatigue

• Baclofen/tizanidine for spasticity

• Oxybutynin for bladder dysfunction

What non‑pharmacologic strategies help manage MS?

• Avoid heat exposure

• Smoking cessation

• Physical therapy

• Occupational therapy

What complications can occur in MS?

• Progressive disability

• Spasticity

• Bladder dysfunction

• Cognitive impairment

• Depression

• Mobility impairment

How is MS monitored over time?

• MRI for new lesions

• Track relapse frequency

• Monitor medication side effects

• Evaluate functional status

What lifestyle modifications help prevent MS progression?

• Smoking cessation

• Vitamin D optimization

• Avoid overheating

What is the most common initial presenting symptom of MS?

Optic neuritis.

What symptom is triggered by heat exposure in MS?

Uhthoff’s phenomenon.

What neurologic sign produces an electric shock sensation with neck flexion?

Lhermitte’s sign.

What MRI pattern is classic for MS?

Periventricular lesions oriented perpendicular to the ventricles (“Dawson’s fingers”).

What CSF finding is most strongly associated with MS?

Oligoclonal bands.

What is the best acute treatment for MS relapse?

IV high‑dose glucocorticoids

What is the best disease‑modifying therapy class for relapsing MS?

Interferon beta or glatiramer acetate

What is the best treatment for steroid‑refractory MS relapse?

Plasmapheresis