What is transverse myelitis?

Transverse Myelitis: Definition and Management

Transverse myelitis is an inflammatory disorder of the spinal cord characterized by acute or subacute spinal cord dysfunction resulting in motor weakness, sensory abnormalities, and autonomic (bladder, bowel, and sexual) impairment below the level of the lesion. 1

Etiology

Transverse myelitis can be associated with various underlying conditions:

• Demyelinating diseases:

  • Multiple sclerosis
  • Neuromyelitis optica (NMO)
  • MOG antibody-associated disorders

• Systemic autoimmune diseases:

  • Systemic lupus erythematosus
  • Sjögren's syndrome

• Infectious/parainfectious causes:

  • HIV
  • Cytomegalovirus
  • Epstein-Barr virus
  • Zika virus
  • Chikungunya virus
  • West Nile virus 2, 1

• Other causes:

  • Immune checkpoint inhibitor therapy (as an immune-related adverse event)
  • Paraneoplastic syndromes
  • Drug/toxin-induced 2, 3

Diagnostic Evaluation

Imaging

• MRI of spine with and without contrast - gold standard for evaluation
  • Look for hyperintense lesions on T2 sequences
  • Lesions extending over 3 vertebral segments suggest NMO 1
  • Thin axial cuts through the region of suspected abnormality 2

Laboratory Tests

• Cerebrospinal fluid analysis:

  • Cell count (may show pleocytosis)
  • Protein (often elevated)
  • Glucose
  • Oligoclonal bands
  • Viral PCRs
  • Cytology
  • Onconeural antibodies 2, 1

• Blood tests:

  • B12
  • HIV
  • RPR (syphilis)
  • ANA
  • Ro/La antibodies
  • TSH
  • Aquaporin-4 IgG (for NMO)
  • MOG antibodies 2, 1

Additional Evaluation

• Neurologic consultation
• MRI of brain (to evaluate for demyelinating diseases)
• Evaluation for urinary retention and constipation 2

Treatment

Acute Management

• First-line treatment: High-dose methylprednisolone (1g/day IV for 3-5 days)

  • Should be initiated as soon as possible, ideally within hours of diagnosis 1
  • Rule out strongyloidiasis prior to steroid use 2

• Second-line treatments (for non-responders):

  • Intravenous immunoglobulin (IVIG): 2g/kg divided over 5 days
  • Plasmapheresis for severe cases 2, 1

Special Considerations

• For immune checkpoint inhibitor-related transverse myelitis:

  • Permanently discontinue immune checkpoint inhibitor
  • Consider higher doses of methylprednisolone (1g/day for 3-5 days)
  • Strongly consider IVIG 2

• For autoimmune disease-associated transverse myelitis:

  • May require cyclophosphamide in combination with methylprednisolone
  • Consider anticoagulation in patients with positive antiphospholipid antibodies 1, 4

Prognosis

The long-term outcome typically follows a rule of thirds:

• One-third recover with few or no sequelae
• One-third develop moderate permanent disability
• One-third suffer severe disability 1

Poor Prognostic Factors

• Extensive lesions on MRI
• Reduced muscle strength or sphincter dysfunction at onset
• Positive antiphospholipid antibodies
• Delayed treatment initiation (>2 weeks) 1

Clinical Pearls

• Neurological response typically occurs within days to 3 weeks
• Relapses are common (50-60%) during corticosteroid tapering
• Early aggressive treatment is essential to minimize neurological damage
• Consider underlying systemic conditions in all patients with transverse myelitis