Eosinophilic Granulomatosis with Polyangiitis Presenting with Intermittent Claudication.

Intermittent claudication (IC), characterized by lower limb weakness and pain during walking that resolves with rest, is most commonly caused by lumbar spinal canal stenosis or peripheral arterial disease. We report a unique case of eosinophilic granulomatosis with polyangiitis (EGPA) presenting with IC. An 80-year-old woman presented with fever, muscle pain, muscle weakness, and IC. She had a history of bronchial asthma and allergic rhinitis. Laboratory tests revealed eosinophilia (4,212 /μL) and elevated creatine kinase levels (505 U/L). Magnetic resonance imaging (MRI) with short tau inversion recovery sequences demonstrated diffuse high-signal intensity across multiple skeletal muscles. A biopsy specimen of the right biceps brachii, taken from a high-signal area identified on MRI, showed inflammatory cell infiltration, primarily composed of eosinophils and lymphocytes in the blood vessel walls. The patient was diagnosed with EGPA-associated skeletal muscle involvement and treated with a moderate dose of glucocorticoids, resulting in significant clinical improvement. This case highlights that EGPA can present with IC, a rare manifestation of the disease, and underscores the diagnostic value of MRI in such cases. MRI may be a useful tool for localizing biopsy sites in patients with EGPA-related muscle damage. Clinicians should consider anti-neutrophil cytoplasmic antibody-associated vasculitis, including EGPA, in patients presenting with IC and systemic symptoms, and initiate early diagnostic and therapeutic interventions.