Embolic Ischemic Stroke Associated with Maintenance Intravenous Immunoglobulin Therapy

We describe the case of a 51-year-old man who experienced an embolic ischemic stroke during long-term maintenance of intravenous immunoglobulin (IVIG) therapy for chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). At 43 years of age, he was diagnosed with CIDP and had tolerated IVIG well. Immediately after completing the 112th infusion, he exhibited acute right-hand clumsiness. Brain magnetic resonance imaging revealed an acute embolic infarction, and neither risk factors for ischemic stroke nor alternative embolic sources were identified. Although IVIG is generally considered safe, this case highlights that embolic stroke may occur even in relatively younger, low-risk patients during uneventful maintenance IVIG therapy, warranting continued vigilance.