Neurology · Hard
This case is fictional and exists for study. It describes no real patient.
28 years · female
A 28-year-old female presents to the acute medical unit with a 4-day history of painful, progressive loss of vision in her right eye, which worsens with eye movement. She also notes reduced colour perception in the affected eye. She reports a similar self-limiting episode 14 months ago consisting of left leg weakness and numbness that completely resolved over 3 weeks without medical intervention. On clinical examination, visual acuity is 6/36 in the right eye and 6/6 in the left eye. There is a right relative afferent pupillary defect (RAPD). Lower limb neurological examination reveals hyperreflexia and an extensor plantar response on the left side.
Vital signs
- HR
- 76 bpm
- BP
- 118/74 mmHg
- RR
- 14/min
- Temp
- 36.7 °C
- SpO₂
- 99%
Examination findings
- Right relative afferent pupillary defect (RAPD)
- Visual acuity 6/36 in right eye
- Left lower limb hyperreflexia and left extensor plantar response
- Pain on right extraocular movements
Investigations
| Haemoglobin | 13.2 g/dL | reference: 12.0-15.5 |
| White Cell Count | 6.8 10^9/L | reference: 4.0-11.0 |
| C-Reactive Protein (CRP) | 2 mg/L | reference: 0-5 |
| Erythrocyte Sedimentation Rate (ESR) | 11 mm/hr | reference: 0-20 |
Question 1 of 3
Which of the following is the most likely diagnosis?
The patient demonstrates evidence of demyelinating lesions disseminated in both space (optic nerve presenting currently as optic neuritis, and spinal cord/corticospinal tract causing upper motor neuron signs in the left leg) and time (current episode + previous distinct neurological deficit 14 months ago). This fulfills the McDonald criteria for relapsing-remitting multiple sclerosis (RRMS). Clinically isolated syndrome (CIS) applies only to a single first clinical episode of demyelination. Neuromyelitis optica spectrum disorder typically presents with severe bilateral optic neuritis or transverse myelitis, often with serum anti-AQP4 antibodies. Acute disseminated encephalomyelitis (ADEM) is a monophasic demyelinating illness usually post-viral, characterized by encephalopathy.
Teaching point: Multiple sclerosis requires demonstration of central nervous system lesions disseminated in both space and time.
Question 2 of 3
Which of the following is the single most appropriate initial investigation to confirm the diagnosis?
MRI of the brain and spine with contrast (gadolinium) is the gold standard imaging modality and initial diagnostic test of choice for suspected multiple sclerosis. It non-invasively evaluates lesions disseminated in space and time (showing periventricular, juxtacortical, infratentorial, or spinal cord demyelinating plaques). Lumbar puncture showing CSF-restricted oligoclonal bands and VEP are useful adjunctive investigations when MRI criteria are inconclusive, but MRI remains the primary initial investigation. Serum AQP4 testing is used to rule out neuromyelitis optica spectrum disorder.
Teaching point: MRI of the brain and spine with gadolinium enhancement is the primary investigation of choice to evaluate suspected multiple sclerosis.
Question 3 of 3
Which of the following is the most appropriate management step to treat her current visual symptoms?
The management of acute relapse in multiple sclerosis (such as acute optic neuritis causing functional impairment) involves high-dose corticosteroids—either oral or intravenous methylprednisolone (e.g., 500 mg–1000 mg daily for 3–5 days). Low-dose prednisolone is ineffective and historically associated with higher recurrence rates of optic neuritis. IVIg and plasma exchange are reserved for severe, refractory relapses that fail to respond to high-dose steroids.
Teaching point: Acute demyelinating relapses in multiple sclerosis are treated with a short course of high-dose corticosteroids to accelerate recovery.
Key learning points
- Diagnosis of multiple sclerosis relies on demonstrating demyelinating events disseminated in time and space.
- MRI of the brain and spinal cord with gadolinium enhancement is the imaging modality of choice.
- Acute MS relapses causing significant visual or functional impairment are treated with high-dose methylprednisolone for 3-5 days.
This is one of 158 free cases
AskPreceptor is a study tool for medical students: answer first, then see the reasoning — including why each wrong option is wrong. Free, no sign-up required.