Multiple sclerosis

Vignette says a 32 year old female presents to the neurology clinic with intermittent episodes of limb weakness and sensory disturbances in her left leg over the past 18 months; She reports numbness and tingling in her left leg, along with mild weakness for 7 days and her symptoms are particularly worse in hot climate, and after exercise; Over the past few months, she also reports of blurry vision in her right eye, with pain on eye movements and also urinary incontinence; Vital signs are normal; Examination findings show:-
Motor:- Mild weakness with MRC grade of 4/5 in the left leg and 5/5 in the right leg.
Sensory:- Decreased sensation to light touch and vibration in the left leg.
Reflexes:- Hyperreflexia in the left leg with positive Babinski sign on the left leg.
Cranial nerves:- Decreased visual acuity in the right eye with positive relative afferent pupillary defect (RAPD) in the right eye. Fundoscopic examination is normal.
MRI of the brain and spinal cord shows multiple hyperintense lesions (i.e. demyelinating lesions) within the periventricular areas on T2/FLAIR images; CSF analysis shows IgG oligoclonal bands; Visual evoked potential shows delayed latency in the right eye; Diagnosis?

Diagnosis is Multiple sclerosis (i.e. relapsing remitting multiple sclerosis).

Multiple sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system.

Types:-

1. Relapsing remitting type (MC type)

2. Primary progressive type

3. Secondary progressive type

Presents with fatigue, sensory deficits, motor weakness, autonomic disturbances, cranial nerve deficits, and visual disturbances (e.g. optic neuritis, INO); Higher prevalence in individuals residing in the northern part (due to vitamin D deficiency); Associated with Uhthoff's phenomenon (i.e. symptoms worse in heat), Lhermitte's sign (i.e. radicular pain in legs with neck flexion); Urinary incontinence (i.e. urge incontinence).

Optic neuritis is the first presenting symptom of multiple sclerosis; Presents with vision loss, pain with eye movements, RAPD or Marcus gunn pupil, color vision deficiency and Uhthoff’s phenomenon. Fundoscopy is normal in the acute phase but shows optic disc pallor in the chronic phase.

Diagnosis:-

1. MRI of the brain and spinal cord shows multiple hyperintense lesions (i.e. demyelinating lesions) within the periventricular, juxtacortical and infratentorial areas on T2/FLAIR images i.e. multiple sclerotic plaques (demyelinating lesions) within the periventricular, juxtacortical and infratentorial areas.

2. CSF analysis shows IgG oligoclonal bands.

3. Visual evoked potential tests.

Management:-

1. Acute attacks are managed with high dose corticosteroids (e.g. IV methylprednisolone).

2. Disease-modifying therapies are the mainstay of treatment of relapsing-remitting MS;

Disease modifying drugs are:-

a. Interferon-beta

b. Fingolimod

c. Natalizumab (associated with progressive multifocal leukoencephalopathy due to JC virus reactivation)

d. Glatiramer

e. Rituximab

3. Symptomatic measures are gabapentin for neuropathic pain, baclofen for spasticity, oxybutynin (muscarinic cholinergic antagonist) for urge incontinence, SSRIs for major depression disorder and modafinil for fatigue.

4. Supportive measures are exercise, avoid excessive heat, smoking cessation, and vitamin D supplementation.