Clinical Manifestations of Acute Transverse Myelitis
Acute Transverse Myelitis (ATM) typically presents with a combination of motor weakness, sensory symptoms, and bowel/bladder dysfunction that develops over hours to days, with progression to maximum severity within 4 hours to 21 days.
Core Clinical Manifestations
Motor Symptoms
- Bilateral limb weakness (paraparesis or quadriparesis)
- Rapidly progressive paralysis
- Spasticity
- Hyperreflexia
- Positive Babinski signs
Sensory Symptoms
- Sensory level deficit (clear demarcation of sensory loss below a specific spinal level)
- Paresthesias
- Numbness
- Pain (often radicular or band-like around the trunk)
- Loss of vibration and proprioception
Autonomic Dysfunction
- Urinary retention or incontinence
- Bowel dysfunction (constipation or incontinence)
- Sexual dysfunction
- Cardiovascular instability in high cervical lesions
Specific Presentations Based on Lesion Level
Cervical Lesions
- Quadriparesis/quadriplegia
- Respiratory insufficiency (may require ventilatory support if vital capacity falls below 15 ml/kg) 1
- Diaphragmatic weakness
- Four-limb sensory disturbances
Thoracic Lesions
- Paraparesis/paraplegia
- Truncal sensory level
- Preserved upper limb function
- Thoracic band-like pain
Temporal Profile
- Acute onset: Symptoms develop over hours to days
- Progression to nadir: 4 hours to 21 days 2
- May be preceded by prodromal illness (fever, respiratory or gastrointestinal infection) in 30-60% of cases
Diagnostic Indicators
MRI Findings
- Longitudinally extensive spinal cord lesion (≥3 vertebral segments) 3
- T2 hyperintensity within the spinal cord
- Spinal cord swelling
- Gadolinium enhancement may be present
CSF Abnormalities
- Neutrophilic pleocytosis 3
- Elevated protein levels
- Absence of oligoclonal bands (helps distinguish from multiple sclerosis)
Variants and Associated Conditions
ATM may present as part of:
- Idiopathic ATM (most common)
- Multiple sclerosis
- Neuromyelitis optica spectrum disorders (check for AQP4-IgG)
- MOG-antibody associated disease
- Post-infectious/parainfectious myelitis
- Systemic autoimmune diseases (SLE, Sjögren's syndrome) 4
- Paraneoplastic syndromes
Severity Indicators and Prognostic Factors
Poor prognostic factors include:
- Rapid progression to maximum deficit (<24 hours)
- Complete paralysis
- Sphincter dysfunction at onset
- Extensive lesions on spinal MRI
- Delayed treatment initiation 1
Complications
- Respiratory failure (in high cervical lesions)
- Pressure ulcers
- Deep vein thrombosis
- Urinary tract infections
- Spasticity
- Neuropathic pain
- Permanent disability
Diagnostic Criteria
The diagnosis of ATM requires all of the following 5:
- Bilateral signs/symptoms attributable to spinal cord dysfunction
- Clearly defined sensory level
- Progression to maximum deficit between 4 hours and 21 days
- Evidence of inflammation within the spinal cord (CSF pleocytosis, elevated IgG index, or MRI enhancement)
- Exclusion of compressive, vascular, infectious, and other causes
Early recognition of these clinical manifestations is critical for prompt diagnosis and treatment initiation, which may significantly impact long-term outcomes and reduce permanent disability 6.