A 45-year-old woman with multiple sclerosis presents with acute severe vertigo, horizontal nystagmus, and intention tremor. Vital signs show BP 128/82, HR 88, RR 16, Temp 37.2°C, SpO2 98% on room air. MRI brain reveals a new T2/FLAIR hyperintense lesion in the right cerebellar hemisphere with no contrast enhancement. CSF oligoclonal bands are positive. She denies fever or recent infections. High-dose intravenous methylprednisolone is initiated. Which pathophysiologic mechanism best explains demyelination in her lesion?
- A)Toxic accumulation of myelin breakdown products
- B)Primary axonal degeneration with secondary demyelination
- C)Ischemic necrosis from vascular occlusion
- D)Immune-mediated demyelination with preserved axonsGABARITO
- E)Viral-induced cytolysis of oligodendrocytes
Explicação
Demyelinating diseases like MS involve immune-mediated attack on myelin sheaths by T cells and B cells, with relative sparing of axons in the acute phase. This reversible demyelination allows for potential recovery with treatment, unlike primary axonopathies. ... Ver explicação completa e trilha adaptativa →