Intravenous Immunoglobulin-Associated Severe Hemolytic Anemia.

Intravenous immunoglobulin (IVIG) is used to treat immunodeficiency conditions, neuro-immunological, infection-related, autoimmune, and inflammatory disorders and is typically well tolerated. A hematological adverse reaction such as hemolytic anemia and neutropenia is known to occur with IVIG, which is usually transient and subclinical. However, severe hemolytic anemia is known to occur in some cases. We present a case of a 66-year-old man who developed severe symptomatic hemolytic anemia after receiving IVIG for acute inflammatory demyelinating polyneuropathy (AIDP). The patient had known risk factors such as non-O blood group, high cumulative dose of IVIG, and underlying autoimmune condition, which would have put him at high risk for developing hemolytic anemia after IVIG. Therefore, it is prudent for clinicians to have increased awareness regarding the potential for severe hemolysis and closely monitor these patients with risk factors after treatments to identify this adverse reaction before more severe complications occur.