Multiple Sclerosis - Neuro

Question 1

Risk factors

Answer 1

• Living farther from the equator
• Family history – risk 7X higher if first degree relative has MS
• Epstein-Barr Virus (EBV) infection is a possible environmental factor in genetically predisposed persons

Question 2

Pathophysiology

Answer 2

• autoimmune disease
• scar tissue (sclerosis) in the brain and/or spinal cord. The scar tissue or plaques form when the protective and insulating myelin covering the nerves is destroyed, a process called demyelination. Without the myelin, electrical signals transmitted throughout the brain and spinal cord are disrupted or halted. The brain then becomes unable to send and to receive messages.
• Inflammatory plaques originating in the integrity of the blood-brain barrier
• Leukocytes entering central nervous system (CNS) create inflammatory process
• Other inflammatory mediators
• Eventual destruction of myelin and gradual progression of neurocognitive decline

Question 3

Clinical presentation

Answer 3

• Sensory deficits: Transient sensory deficits are the most common initial presentation (40-50%): Paresthesia- diminished sensation in upper or lower extremities
• Visual and occulomotor deficits: Acute monocular visual loss due to optic neuritis (15-20%), Failure of adduction of eye, Coarse nystagmus in the abducting eye, Other oculomotor function remain intact, Insidious variety particularly common in older patients, Legs more commonly involved, Positive bilateral Babinski’s sign even in patients with unilateral problems
• Motor and cerebellar deficits:Ataxia, Intention tremor
• Autonomic deficits: Urinary difficulties caused by upper motor nerve injury in the spinal cord
• Cerebral paroxysmal symptoms: Later manifestations-Memory loss, Personality change, Emotional lability
• Fatigue: related to high circulating levels of immunomodulators, May predate exacerbations

Question 4

Signs and Symptoms

Answer 4

• Ocular
• Fatigue
• Difficulty with gait and balance: Ataxia and tremor (80%)
• Spasticity
• Uthoff phenomenon

Question 5

Ocular symptoms

Answer 5

• Ocular neuritis (66% at presentation)
• Diplopia and pain with eye movements
• Sudden vision loss
• Blurry vision
• Reduced perception of light
• Poor color vision
• Symptoms may be exacerbated by exercise, stress, or heat
• Usually resolve within 4-6 weeks

Question 6

Fatigue symptoms

Answer 6

• Most common symptom of MS
• Affects 80% of patients
• More debilitating in patients with progressive disease or those with gait difficulties
• Other causes must be ruled out

Question 7

Spasticity symptoms

Answer 7

Seen in 60% of MS patients

May lead to:

• Pain
• Spasms
• Reduced mobility
• Limited range of motion
• Contractures
• May mask underlying weakness and ataxia

Question 8

Uthoff Phenomenon

Answer 8

• Blurred vision caused by increased body temperature
• Present in 60-80%
• High temperatures may worsen symptoms:
• Fatigue (most common)
• Decreased concentration
• Weakness
• Urinary urgency
• Lhermitt sign: Electric-like sensation radiating down the back and limbs when bending the neck
• Pain

Question 9

Relapsing Remitting Disease

Answer 9

• 85-90% of patients at diagnosis
• Characterized by attacks followed by complete or nearly complete remission
• Any residual manifestations remain stable between relapses
• Relapses and remissions can last months to years without development of new symptoms
• New episodes occur erratically (1-5/yr)
• Some patients present with clinically issolated syndrome yet develop new, asymptomatic white mater lesions on serial brain MRI without new clinical symptoms

Question 10

Secondary Progressive Disease

Answer 10

• Probably a second stage of relapsing remitting MS
• Occurs in >50% of patients
• Distinct exacerbations with no symptom-free remissions
• Progressive neurocognitive decline
• Mean progression is 19years
• Men often have more rapid progression
• Older patients progress faster

Question 11

Primary Progressive Disease

Answer 11

• 10-15% of cases
• 10% of patients presenting later in life (40-60 years)
• Steady decline from diagnosis without remissions
• Tends to be associated with prominent spinal cord involvement

Question 12

Progressive Relapsing Disease

Answer 12

• Least common subtype
• Constant decline with exacerbations
• Without any symptom-free remissions

Question 13

Goals of McDonald Criteria

Answer 13

• Enable early diagnosis and prompt treatment

- To make MS easier to distinguish from other conditions

Question 14

Imaging and Tests

Answer 14

• MRI most useful imaging tool for diagnosis
• Gadolinium-enhancing lesions found in ~60% of early stage MS patients, but usually decrease during the prolonged progressive phases
• MRI will illustrate focal or confluent abnormalities in white matter in 95%
• Serial MRIs document extent, progression, and response to treatment
• Newer imaging techniques can also detect lesions is gray matter

Question 15

Cerebral Spinal Fluid Evaluation

Answer 15

• The standard for supporting the diagnosis of MS

- Does not reflect disease activity or any treatment patient has received

Question 16

Goals of Treatment

Answer 16

• Treating acute exacerbations
• Preventing progressing
• Reducing the number of relapses
• Providing supportive care

Question 17

Recommendations

Answer 17

• MRI performed or repeated 3 months after clinically suspicious episode
• Corticosteroid therapy should be used to shorten the duration of MS relapses and accelerate recovery
• Disease-modifying treatment should be started early in the course of MS to minimize irreversible axonal damage.

Question 18

Disease Modifying Treatment

Answer 18

• Glatiramer and the beta interferons have different mechanisms of action. Patients with MS who have an unsatisfactory response to beta interferons should be considered for glatiramer therapy.
• Patients with worsening forms of MS may be referred for mitoxantrone therapy; however, this agent has acute short-term adverse effects, as well as serious long-term adverse effects that include cardiotoxicity.