[Advances in the treatment of thrombotic thrombocytopenic purpura].

Thrombotic thrombocytopenic purpura (TTP) is a fatal thrombotic disease caused by a marked decrease in the activity of ADAMTS13, a von Willebrand factor cleaving protease. In congenital TTP, ADAMTS13 activity is decreased by an abnormality in ADAMTS13, and in acquired TTP, by anti-ADAMTS13 autoantibody. Death from thrombosis in the acute phase has been an issue with conventional treatment of acquired TTP by plasma exchange or immunosuppressive therapy. However, the advent of caplacizumab, an anti-VWF nanobody, has made it possible to suppress thrombus formation and is expected to improve survival rates. In addition, some case series have shown the efficacy of caplacizumab without plasma exchange for acquired TTP, and this approach is being investigated in clinical trials. Fresh-frozen plasma is transfused to supply ADAMTS13 for congenital TTP, but frequent transfusions over a long period of time can lead to problems such as infection and allergic reactions. Novel therapies such as recombinant ADAMTS13 products and gene therapy are now under development, and show promise for future clinical use.

Successful Treatment of Antibody-mediated Pure Red Cell Aplasia Induced by Continuous Erythropoietin Receptor Activator with Prednisolone.

Pure red cell aplasia (PRCA) associated with erythropoiesis-stimulating agents (ESAs), which were first reported in 1998, usually occurs with subcutaneous administration of epoetin alfa (Eprex®). Improvements in ESA storage, handling, and administration methods have reduced the PRCA incidence. Continuous erythropoietin receptor activator (CERA) is a third-generation ESA that is rarely reported to induce PRCA. We herein report a case of CERA-induced PRCA presenting with positive anti-erythropoietin (EPO) and anti-CERA antibodies, which was successfully treated with prednisolone. Clinicians should be aware of the possibility of antibody-mediated PRCA induced by an ESA in CKD patients with anemia with reticulocytopenia and low serum EPO levels.

[Mantle cell lymphoma with central nervous system relapse successfully treated with nasogastric-tube administration of ibrutinib].

Central nervous system (CNS) involvement in mantle cell lymphoma (MCL) is uncommon. Here we present the case of a 70-year-old male patient who was diagnosed with classic MCL in 2015. The patient achieved complete remission (CR) in 2017 but relapsed with CNS involvement in 2019. He entered a deep coma and was treated with ibrutinib (560 mg daily) via nasogastric tube. He regained full consciousness after 15 days, and the presence of lymphoma cells in his cerebrospinal fluid disappeared 3 months later. We believe that ibrutinib administration via nasogastric tube is effective for MCL patients with CNS relapse.