Demyelinating Diseases USMLE Step 1 Practice Question
A 7-year-old girl presents with fever (39.2°C), headache, and generalized tonic-clonic seizures. Vital signs show HR 110/min, RR 22/min, BP 105/68 mmHg, SpO2 98% on room air. MRI reveals multifocal white matter lesions in both hemispheres. CSF analysis demonstrates lymphocytic pleocytosis (85 cells/μL) without oligoclonal bands. Serum and CSF measles IgM antibodies are positive. She denies recent immunizations. Which of the following is the most likely diagnosis?
Answer choices
- AAcute disseminated encephalomyelitisCorrect answer
- BAcute viral encephalitis
- CSubacute sclerosing panencephalitis
- DCNS lymphoma
- EMultiple sclerosis
- FProgressive multifocal leukoencephalopathy
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