A Metastatic Signet Ring Cell Carcinoma Presented as Acquired Thrombotic Thrombocytopenic Purpura: A Case Report.

Microangiopathic hemolytic anemia (MAHA) may occur as a paraneoplastic syndrome in some solid tumors, but MAHA accompanied by signet ring cell carcinoma (SRCC) of an unknown origin is very rare. We report a patient who presented with an acute onset of Coombs negative hemolytic anemia and frequent schistocytes in the peripheral blood smear which are typical for MAHA as initial presentation of metastatic SRCC. Our patients fulfilled the criteria of thrombotic thrombocytopenic purpura (TTP) and received the specific treatment for TTP without improvement.