Cerebral Infarction and Myalgia in a 75-year-old Man with Eosinophilic Granulomatosis with Polyangiitis.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare condition of systemic vasculitis of small to medium-sized blood vessels. We herein report the case of a 75-year-old man who presented with hemiplegia on his right side due to cerebral infarction following myalgia and a high fever. He had no history of asthma or allergic rhinitis. He was diagnosed with EGPA based on the presence of eosinophilia, sinusitis suggested by magnetic resonance imaging, and muscle pathology. His hemiplegia improved rapidly after corticosteroid therapy. This case suggests that EGPA should be a differential diagnosis of cerebral infarction with myalgia and eosinophilia.