First Report of Eltrombopag Induced Severe Autoimmune Hemolytic Anemia in the Management of Waldenström Macroglobulinemia-associated Autoimmune Thrombocytopenia

Abstract Background: Autoimmune thrombocytopenia (ITP) and autoimmune hemolytic anemia (AIHA) can be observed in Waldenström Macroglobulinemia (WM). The cause of AIHA should be carefully distinguished during the disease management. Case Presentation: A 63-year-old female WM patient complicated with thrombocytopenia, who was admitted to our department with a complaint of abdominal pain. After first half of bortezomib/dexamethasone/rituximab (BRD) chemotherapy, her platelet level recovered, but subsequently decreased to extremely low level (around 1-2×109/L), and the patient suffered from platelet transfusion refractoriness. During the management of refractory thrombocytopenia, the patient developed severe hemolytic anemia, and further tests confirmed warm AIHA. FcγRIIα polymorphism test showed that the patient had FcγRIIα-131RH, which implied that the AIHA may not be WM-related. Given the effects of ibrutinib in controlling WM, ibrutinib single treatment was started, which quickly corrected the thrombocytopenia within five days, but not hemolysis. With a relatively safe platelet level, eltrombopag was stopped, and the hemolysis alleviated within three days after eltrombopag withdrawal. Conclusion: This is the first report on eltrombopag-induced AIHA, and we should always keep in mind of the drug induced hemolysis even in disorders with autoimmune background.