Clinical Features of Transverse Myelitis
Transverse myelitis (TM) is characterized by acute or subacute inflammation of the spinal cord resulting in bilateral neurological symptoms including motor weakness, sensory disturbances, and autonomic dysfunction that typically evolve over hours to days, with most cases progressing to maximal clinical severity within 10 days of onset.
Key Clinical Manifestations
Motor Symptoms
- Bilateral limb weakness (paraparesis or paraplegia)
- At maximal severity, approximately 50% of patients develop complete paraplegia 1
- Progressive ascending weakness pattern
- Spasticity (may develop in later stages)
Sensory Symptoms
- Sensory level (clear demarcation of altered sensation)
- Paresthesias (tingling, numbness)
- Band-like dysesthesias (reported in 80-94% of patients) 2
- Pain (often localized to the back or radiating in a dermatomal pattern)
Autonomic Dysfunction
- Bladder dysfunction (virtually all patients) 1
- Bowel incontinence or constipation
- Sexual dysfunction
- In severe cases, cardiovascular instability and respiratory failure may occur 3
Diagnostic Approach
MRI Findings
- Focal spinal cord lesion(s) with T2 hyperintensity
- Lesion characteristics:
- Shape: cigar-like (sagittal view), wedge-shaped (axial view)
- Size: typically small, but can extend ≤2 vertebral segments
- Location: commonly cervical or thoracic regions, affecting peripheral regions and lateral/posterior columns 4
- Signal characteristics: T2 hyperintensity, possible gadolinium enhancement
Laboratory Findings
- Cerebrospinal fluid analysis may show:
- Pleocytosis
- Elevated protein
- Oligoclonal bands (particularly in MS-associated TM) 3
- Serum testing for:
- AQP4-IgG antibodies (neuromyelitis optica)
- MOG-IgG antibodies
- Autoimmune markers (ANA, RF, anti-phospholipid antibodies)
Clinical Course and Prognosis
The clinical outcome follows a rule of thirds 2:
- One-third of patients recover with minimal or no sequelae
- One-third have moderate permanent disability
- One-third suffer severe permanent disability
Prognostic Factors
- Poor prognostic indicators include:
- Extensive lesions on spinal MRI
- Reduced muscle strength or sphincter dysfunction at onset
- Positive antiphospholipid antibodies
- Delayed initiation of treatment 3
- Favorable prognostic factors:
- Early treatment initiation
- Prompt neurological response
- Absence of extensive MRI lesions 3
Treatment Approach
Acute Management
- High-dose intravenous methylprednisolone (1g/day for 3-5 days) should be administered as soon as possible after diagnosis, ideally within the first few hours 3
- For patients who don't respond to steroids, plasma exchange (5-10 sessions on alternate days) should be considered 3, 5
- IV immunoglobulin (2g/kg divided over 5 days) may be used as an alternative 3
- In severe or refractory cases, consider cyclophosphamide or rituximab 3
Management of Complications
- Neuropathic pain: pregabalin, gabapentin, or duloxetine 3
- Spasticity: baclofen, tizanidine, or physical therapy 3
- Bladder dysfunction: intermittent catheterization, anticholinergics
- Respiratory monitoring: consider early intubation if vital capacity falls below 15 ml/kg 3
Important Considerations
- Rule out infectious causes before starting immunosuppression 3
- Monitor for development of other demyelinating conditions (MS, NMO)
- Consider maintenance immunosuppressive therapy to prevent relapses in recurrent cases 3
- Permanently discontinue immune checkpoint inhibitor therapy if it's the suspected cause 3
Differential Diagnosis
- Multiple sclerosis
- Neuromyelitis optica spectrum disorders
- Acute disseminated encephalomyelitis
- Spinal cord infarction
- Compressive myelopathy
- Infectious myelitis (viral, bacterial, parasitic)
- Systemic autoimmune disorders (SLE, Sjögren's syndrome)
- Paraneoplastic syndromes
Early recognition and prompt treatment are essential to minimize long-term disability in patients with transverse myelitis.