Thanks to Amran for presenting the case of an elderly woman with history of “transverse myelitis” 10 years ago who presented with b/l leg weakness, numbness, and tingling, found to have several spinal cord enhancements as well as optic chiasm enhacement on T2 FLAIR imaging concerning for MS vs NMO!

Clinical pearls

• MS and NMO most commonly affect women (2:1 and 10:1 respectively).
• To meet diagnostic criteria for MS, patients must demonstrate CNS lesions in both space and time via clinical or MRI findings.
• NMP affects the optic nerve and spinal cord much more so than the brain/brainstem.
• Presence of AQP4 serum antibodies are specific to NMO.
• Treatment for acute MS flare or NMO flare involves high dose steroids or plasma exchange.
• The most effective chronic treatment for relapsing/remitting MS is natalizumab, not effective for NMO and may even be harmful.

Framework for myelopathies:

Demyelinating diseases that present with myelitis:

Multiple sclerosis:

Epi

• Most commonly affects young adults
• Mean age of onset 28-31. Though can present between 15-50
• Affects women 2:1
• Life expectance is reduced by ~10 years

Presentation

• Most common symptoms
  • Sensory disturbances (90%)
    • Numbness, tingling, pins and needles
    • Lhermitte sign (flexion of the neck causes sensation of electric shock that radiates down the spine into the limbs). Can be seen in tumors, cervical disk herniation, and trauma as well.
  • Fatigue and/or sleep disturbance (85%)
    • Unrelated to amount of activity performed
    • Worsened by depression
  • Motor issues and spasticity (80%)
    • Lower extremities most commonly affected
    • Paraparesis, paraplegia
  • Cognitive impairment (70%)
    • Attention, executive function, short term memory
    • Depression (60%) likely contributes
  • Bowel or bladder dysfunction (50-75%)
  • Visual disturbance (25%)
    • Internuclear ophthalmoplegia
      • Lost adduction and horizontal nystagmus of the abducting eye
      • Lesion in the medial longitudinal fasciculus of the brainstem on the side of diminished adduction
      • Convergence is preserved
    • Optic neuritis
      • Unilateral eye pain accentuated by ocular movement
      • Variable degree of visual loss (90% regain normal vision)
• Characteristic features
  • Different types
    • Clinically isolated syndrome (first attack)
    • Relapsing-remitting
    • Secondary progressive
    • Primary progressive
    • Progressive relapsing
  • Heat sensitivity AKA “Uhthoff phenomenon” (80%)
    • Due to slowing of neuronal conduction with increased body temperature
• Diagnosis
  • McDonald Criteria (revised in 2017)
  • Clinical or radiographic
  • CSF studies are not indicated unless atypical presentation
• Treatment
  • Acute episode
    • Glucocorticoids
      • Solumedrol 1 g IV x 3-5 days
    • Plasma exchange
      • If failed glucocortidoids
  • Chronic
    • Disease modifying therapy
      • Good for relapsing-remitting MS