Demyelinating Diseases USMLE Step 1 Practice Question
A 45-year-old woman with multiple sclerosis on interferon-beta presents with progressive cognitive decline, gait disturbance, and blurred vision over 2 months. Vital signs: BP 128/82, HR 88, RR 16, Temp 37.2°C, SpO2 98% on room air. Brain MRI reveals multifocal white matter lesions with enhancement and mass effect. CSF JC virus PCR is positive; oligoclonal bands are negative. Which of the following is the most likely complication?
Answer choices
- AInterferon-induced thyroiditis
- BSecondary progressive MS
- CFingolimod-associated macular edema
- DMS relapse
- EProgressive multifocal leukoencephalopathyCorrect answer
- FNatalizumab-associated posterior reversible encephalopathy syndrome
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