Multiple Sclerosis (MS)
Definition
A chronic inflammatory disease of the CNS characterized by relapsing remitting, or progressive neurologic symptoms due to inflammation, demyelination and axonal degeneration
Clinical Patterns of MS
Epidemiology
Aetiology
Clinical Features
Investigations
Management
Source
Toronto Notes 2012
A chronic inflammatory disease of the CNS characterized by relapsing remitting, or progressive neurologic symptoms due to inflammation, demyelination and axonal degeneration
Clinical Patterns of MS
- Relapsing remitting (RRMS) 85%, primary progressive (PPMS) 10%, progressive relapsing (PRMS) 5%, secondary progressive (SPMS)
- Most RRMS goes on to become SPMS
Epidemiology
- 17-35y
- F>M 3:1
Aetiology
- Genetic
- Environmental (less sun exposure, virus)
Clinical Features
- Symptoms include numbness, visual disturbance (optic neuritis), weakness, spasticity, diplopia (e.g. INO), impaired gait, vertigo, bladder dysfunction
- Lhermitte's sign: flexion of neck causes electric shock sensation down back into limbs indicating cervical cord lesion
- Uhthoff's phenomenon: worsening of symptoms (classically optic neuritis) in heat
- SPMS: classically weakness oflegs in pyramidal distribution paired with cerebellar findings of arms (i.e. intention tremor)
- Symptoms not commonly found in MS: visual field defects, aphasia, apraxia, progressive hemiparesis
- Relapse: acute/subacute onset of clinical dysfunction that peaks from days to weeks, followed by remission with variable symptom resolution (symptoms must last at least 24 h)
- In RRMS, average 0.4 to 0.6 relapses/yr, but higher disease activity in first years of disease
Investigations
- MRI: demyelinating plaques appear as hyperintense lesions on T2 weighted MRI, with active lesions showing enhancement with gadolinium
- typical locations: periventricular, corpus callosum, cerebellar peduncles, brainstem, juxta cortical region, and dorsolateral spinal cord
- Dawson's fingers: periventricular lesions extending into corpus callosum
- cranial MRI is more sensitive than spinal MRI
- CSF: oligoclonal bands in 90%, increased IgG concentration
- Evoked potentials (visual/auditory/somatosensory): delayed but well-preserved wave forms
Management
- IV methylpredisolone
- Consider disease modifying therapy: Interferon B > natalizumab >fingolimod
Source
Toronto Notes 2012