Transverse myelitis
Transverse myelitis is inflammation across one or more contiguous spinal cord segments causing subacute weakness, a sensory level, and bladder or bowel dysfunction; diagnosis requires spinal MRI showing cord enhancement or CSF inflammation with exclusion of compressive and infectious causes, and idiopathic disease is treated with high-dose intravenous methylprednisolone.
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What this article covers
- Overview
Definition: transverse myelitis is an inflammatory, often demyelinating, disorder of the spinal cord affecting one or more contiguous segments, producing motor, sensory, and autonomic dysfunction below the level of the lesion.
- Epidemiology
Age distribution: ITM has a bimodal distribution, with peaks in adolescence/young adulthood and again in middle to older adulthood.
- Risk factors
Recent infection: a preceding viral syndrome or bacterial infection increases risk through a postinfectious immune-mediated mechanism.
- Pathophysiology
Immune-mediated cord inflammation: in idiopathic and postinfectious cases, an aberrant immune response, likely triggered by molecular mimicry between a preceding pathogen and myelin or axonal…
- Clinical features
Core triad: subacute limb weakness, a sensory level (a discrete band below which sensation is impaired), and bladder or bowel dysfunction are the defining features.
- Differential diagnosis
Compressive myelopathy (epidural abscess, tumor, disc herniation, spinal hematoma): shows cord compression rather than intrinsic enhancement without compression on MRI; must be excluded emergently…
- Diagnosis
Establishing basis: the diagnosis requires the clinical syndrome above plus objective evidence of cord inflammation (gadolinium enhancement on MRI or cerebrospinal fluid pleocytosis/elevated IgG…
- Management
First step: exclude, and if present urgently treat, a compressive cause of myelopathy before starting immunosuppression, since glucocorticoids do not address mechanical cord compression and delay to decompression worsens outcomes.
- Complications
Permanent motor and sensory deficits: a substantial proportion of patients are left with residual weakness, sensory disturbance, or gait impairment, particularly when the initial deficit was complete paraplegia or slow to begin improving.
- Prognosis
Recovery trajectory: most improvement in ITM occurs over the first 3 to 6 months, though some recovery can continue for up to 2 years.
- Prevention
No established primary prevention for idiopathic disease: because the trigger for most idiopathic and postinfectious transverse myelitis is not a modifiable exposure, there is no proven strategy to prevent a first episode.
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