Refractory thrombotic thrombocytopenic purpura achieving complete remission with rituximab treatment

Some patients with thrombotic thrombocytopenic purpura (TTP) are refractory to standard treatment regimens comprised of plasma exchange (PEX) and steroids. This report describes a 40-year-old woman with refractory TTP who achieved complete remission (CR) in response to rituximab. She was referred to our institution from a rural hospital with purpura of the extremities, severe thrombocytopenia, anemia, and rapidly progressive disturbance of consciousness. TTP was diagnosed based on the clinical symptoms of TTP, low ADAMTS13 activity (<0.5%), and high ADAMTS13 inhibitor (4.4 BU/ml) titers. High-dose prednisolone was immediately administered and PEX was started. This approach was initially effective, but the thrombocytopenia and disturbance of consciousness worsened on the sixth day of treatment. We considered this patient to have refractory TTP and administered weekly rituximab. CR was achieved on day 20, and the disease status of this patient has remained stable over the long term. Our experience with this patient and five others who were similarly treated at our hospital over the past eight years indicates that rituximab is effective for refractory TTP.