Lupus Transverse Myelitis
A 28-year-old woman with systemic lupus erythematosus on hydroxychloroquine, prednisone 5 mg daily, and azathioprine presents with weakness of both legs and urinary incontinence developing over 6 hours. Power is 2/5 in both lower limbs with hyperreflexia, extensor plantars, and a sensory level at T8. She has no headache, seizures, or confusion. Which investigation is most appropriate immediately?
- A.CT of the brain without contrast
- B.MRI of the brain with contrast
- C.MRI of the spinal cord with contrastCorrect
- D.MR angiography and venography of the brain
Explanation
This patient has acute transverse myelitis, a neuropsychiatric complication of systemic lupus erythematosus, and urgent MRI of the spinal cord is the test that will confirm it. A sensory level, symmetric paraparesis, upper motor neurone signs and sphincter dysfunction localise the lesion to the cord, most commonly the thoracic segments, so imaging must be directed there rather than at the brain. MRI shows a longitudinally extensive hyperintense cord lesion on T2 sequences with variable gadolinium enhancement, and it also excludes a compressive cause such as epidural abscess or haematoma, which would need immediate surgery. Lumbar puncture is performed after imaging to look for pleocytosis, raised protein and to exclude infection, and it should never precede imaging when cord compression is possible. Lupus myelitis is a medical emergency because delay of even hours reduces the chance of neurological recovery; high-dose pulse methylprednisolone plus cyclophosphamide, with plasma exchange in refractory cases, should be started as soon as compression is excluded. Brain imaging, whether CT or MRI, will not show a thoracic cord lesion and this patient has no cerebral symptoms. MR angiography and venography address stroke and cerebral venous sinus thrombosis, which present with headache, seizures or altered consciousness rather than an isolated cord syndrome. Aquaporin-4 and myelin oligodendrocyte glycoprotein antibodies plus antiphospholipid antibodies should also be sent, since they change long-term therapy.
Why each option
- A.
- CT of the brain is insensitive for demyelination and cannot image the thoracic cord, where the lesion clearly lies given the T8 sensory level.
- B.
- Brain MRI is appropriate for lupus cerebritis or stroke, but this patient has no headache, seizures or confusion and her deficit localises to the spinal cord.
- C.
- Correct. A sensory level with paraparesis, hyperreflexia and incontinence demands urgent cord MRI to confirm transverse myelitis and exclude a compressive lesion before lumbar puncture and immunosuppression.
- D.
- MRA and MRV evaluate arterial stroke and venous sinus thrombosis; neither explains an isolated thoracic cord syndrome without any cerebral features.
Reference: EULAR Recommendations for the Management of Systemic Lupus Erythematosus, 2023 update; UpToDate 2025, Neurologic and neuropsychiatric manifestations of SLE
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