[Thrombotic thrombocytopenic purpura during pregnancy refractory to plasma exchange and rituximab]

A 30-year-old woman who was 14 weeks pregnant was admitted to our hospital due to purpura, nasal bleeding, and abdominal pain. She was diagnosed with acquired thrombotic thrombocytopenic purpura (TTP) based on the presence of hemolytic anemia, thrombocytopenia, decreased ADAMTS 13 activity (<0.01 IU/ml), and high ADAMTS 13 inhibitor levels (4.8 BU/ml). Plasma exchange (PE) and steroid therapy were immediately administered. However, because she did not respond to these therapeutic approaches, rituximab was additionally administered on the sixth day of treatment. The level of ADAMTS 13 inhibitor increased to 12.5 BU/ml on the seventh day. Renal insufficiency, disturbed consciousness, and genital bleeding did not improve in spite of daily PE, steroid therapy, and second dose of rituximab. She finally died after sudden convulsions on the 14th day. Although the treatment outcomes of TTP have remarkably improved, some cases are refractory to therapy. Establishment of adequate treatment strategies for acquired TTP in pregnant women is required.