II. Definitions

  1. Myelitis
    1. Spinal Cord Inflammation of various causes including Viral Infections, toxins, autoimmune or vascular conditions
    2. Findings include motor weakness, sensory changes (Paresthesias, numbness, pain) and Urinary Incontinence
  2. Transverse Myelitis
    1. Spinal cord inflammation of a transverse segment of the cord with demyelination and necrosis
    2. Myelitis findings occur below the segment of spinal cord involvement

III. Epidemiology

  1. Incidence (rare): 1.3 to 4.6 per million people
  2. Ages
    1. Most common in children and young adults

IV. Pathophysiology

  1. Spinal cord inflammation due to autoimmune, inflammatory, vascular or infectious causes
  2. Myelitis may be unilateral or bilateral, and may effect only some long tracts but not others
    1. The terms Myelitis, Transverse Myelitis and Acute Transverse Myelitis are used interchangeably
    2. The adjective transverse only describes the distribution, but the causes and management are similar

V. Findings: Symptoms and Signs

  1. See Spinal Cord Syndrome
  2. Timing
    1. Onset over hours to days
    2. Progression over days to weeks
  3. Distribution
    1. Myelitis is typically bilateral but may be unilateral
    2. Myelitis may only cause sensory and motor changes at a few spinal levels (sparing lower cord levels)
    3. Myelitis may effect only some long tracts but not others
  4. Motor weakness
    1. Leg flexors and arm extensors are preferentially affected (pyramidal distribution)
  5. Sensory changes
    1. Paresthesias
      1. Typically initial sensory symptom
      2. Paresthesias ascend from the feet proximally
    2. Numbness
    3. Pain
  6. Autonomic Dysfunction
    1. Urinary Incontinence
    2. Stool Incontinence
    3. Temperature dysregulation
    4. Hypertension
  7. Associated Symptoms
    1. Back pain at or near the level of Myelitis (variably present)

VI. Labs

  1. Cerebrospinal fluid (Lumbar Puncture)
    1. Indicated after structural causes are excluded by neuroimaging
    2. Cerebrospinal fluid (CSF) is normal in 50% of cases

VII. Imaging

  1. MRI Spine with gadolinium contrast
    1. Imaging to include well above the level of involvement
      1. May require combined spine MRIs (e.g. cervico-thoracic MRI or thoracolumbar MRI)
    2. Exclude structural compressive causes (e.g. Epidural Abscess, Epidural Hematoma, acute disc Herniation)
      1. Surgical emergencies if present
    3. May also demonstrate inflammatory cord changes
  2. CT Myelogram
    1. Alternative if MRI contraindicated

IX. Causes: Myelitis

  1. See Acute Flaccid Paralysis
  2. See Acute Flaccid Myelitis
  3. Precautions
    1. Do NOT miss Compressive Neuropathy (e.g. Cauda Equina Syndrome) which is curable with early surgical intervention
  4. Demyelinating Disease (most common cause)
    1. Acute Disseminated Encephalomyelitis (ADEM)
    2. Multiple Sclerosis
    3. Neuromyelitis optica
    4. Post-Vaccination Myelitis
  5. Autoimmune or Inflammatory Myelitis
    1. Ankylosing Spondylitis
    2. Antiphospholipid Antibody Syndrome
    3. Behcet Disease
    4. Celiac Disease
    5. Graft-vs-host disease
    6. Mixed Connective Tissue Disease (MCTD)
    7. Neurosarcoidosis
    8. Scleroderma
    9. Sjogren Syndrome
    10. Systemic Lupus Erythematosus
  6. Bacterial Myelitis
    1. Bartonella Henselae (Cat Scratch Disease)
    2. Borrelia Burgdorferi (Lyme Disease)
    3. Brucellosis melitensis (Brucellosis)
    4. Campylobacter jejuni (e.g. Acute Diarrhea)
    5. Chlamydia psittaci (Psittacosis)
    6. Chlamydia pneumoniae (Chlamydia Pneumonia)
    7. Coxiella Burnetii (Q Fever)
    8. Legionella pneumonia
    9. Leptospira (Leptospirosis)
    10. Mycobacterium tuberculosis
    11. Orientia Tsutsugamushi (Scrub Typhus)
    12. Salmonella paratyphi B (Paratyphoid)
    13. Streptococcus (Group A and B)
    14. Treponema pallidum (Syphilis)
  7. Viral Myelitis
    1. Coxsackievirus (A and B)
    2. Cytomegalovirus (Mono-Like Illness)
    3. DengueVirus
    4. Echoviruses
    5. Enterovirus (70 and 71)
    6. Epstein-Barr Virus (Mononucleosis)
    7. Hepatitis A Virus
    8. Hepatitis CVirus
    9. Herpes Simplex Virus Type 2 (Genital Herpes)
    10. HIV Infection (see HIV related Myelitis)
    11. Influenza A Virus (includes H1N1)
    12. Japanese Encephalitis Virus
    13. MeaslesVirus
    14. Mumps Virus
    15. Poliovirus (1, 2, and 3)
    16. St. Louis EncephalitisVirus
    17. Varicella Zoster Virus (Chicken Pox, Shingles)
    18. West Nile Virus
  8. Parasitic Myelitis
    1. Acanthamoeba (Granulomatous Amebic Encephalitis)
    2. Echinococcus Granulosus (Echinococcosis)
    3. Gnathostoma Angiostrongylus (Eosinophilic Meningitis)
    4. Paragonimus westermani fluke (Paragonimiasis)
    5. Schistomosoma (Schistosomiasis)
    6. Taenia solium (Neurocysticercosis)
    7. Toxoplasma gondii (Toxoplasmosis)
    8. Trypanosoma brucei (African trypanosomiasis, African Sleeping Sickness)
  9. Fungal Myelitis
    1. Actinomyces (Actinomycosis)
    2. Aspergillus (Aspergillosis)
    3. Blastomyces (Blastomycosis)
    4. Cryptococcus (Cryptococcosis)
    5. Coccidioides immitis (Coccidioidomycosis, Valley Fever)
  10. Paraneoplastic Conditions (Antibody mediated)
    1. Various antibodies (e.g. ANNA-2, GAD65, NMDAR)

X. Management

  1. Condition specific management
    1. Consult neurology
    2. Consider infectious disease Consultation if infectious Myelitis is suspected (12% of cases)
  2. Corticosteroids may be indicated in some cases
  3. Compressive neureopathy causes of acute Myelitis are surgical emergencies
    1. Emergent Consultation with Spine Surgery or neurosurgery

XI. Prognosis

  1. Moderate to severe residual deficits remain in two thirds of Transverse Myelitis patients

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