Demyelinating Diseases USMLE Step 1 Practice Question
A 28-year-old man with multiple sclerosis on interferon-beta therapy for 3 years presents with progressive encephalopathy, confusion, and ataxia over 2 months. Vital signs: BP 128/82, HR 92, RR 18, Temp 37.2°C, SpO2 98%. Brain MRI reveals multiple asymmetric white matter lesions without enhancement. Serum JC virus PCR is positive. CSF analysis shows no pleocytosis. Which of the following is the most likely complication?
Answer choices
- AInterferon-induced autoimmune encephalitis
- BInfectious myelitis
- CMS disease progression
- DSecondary progressive MS with dementia
- EProgressive multifocal leukoencephalopathyCorrect answer
- FNatalizumab-associated immune reconstitution inflammatory syndrome
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