Cancer-related TTP: Role of plasma exchange

Abstract

e13527 Background: Thrombotic thrombocytopenic purpura (TTP) is a multisystemic disease classically described by thrombocytopenia, microangiopathic hemolytic anemia, fever, neurologic manifestations and renal dysfunction. It is considered a hematologic emergency for which, the treatment of choice is plasma exchange therapy. However, its diagnosis and treatment can be particularly challenging in the setting of disseminated malignancy, as the misdiagnosis of TTP in a patient with cancer-associated thrombotic microangiopathy (TMA) will lead to ineffective use of plasma exchange and delay the timely delivery of chemotherapy. Moreover, patients with disseminated malignancy respond less often to plasma exchange and have a higher mortality rate. Methods: Three patients with disseminated malignancy who presented as TTP are discussed. Two of the three patients were given plasma exchange and had fatal outcomes, while the third patient received chemotherapy as the initial therapy and survived hospitalization. The three patients had prolonged PT with normal aPTT; LDH levels (>1,000 IU/L); and presence of schistocytes in the peripheral blood smear. Results: TMA associated with disseminated malignancy remains a challenging and underdiagnosed condition with very poor prognosis. Plasma exchange has no clinical use is potentially even life-threatening especially when it delays the administration of the appropriate chemotherapy which is the ultimate treatment for the underlying malignancy that resulted in TMA. We propose that the following criteria be used for diagnostic consideration of disseminated malignancy-associated TMA: evidence of hemolysis; leukoerythroblastic picture on the peripheral blood; coagulopathy consisting of elevated d-dimer, prolonged PT with normal aPTT; extreme elevations in the LDH levels (>1,000 IU/L); and presence of schistocytes in the peripheral blood smear. Such patients should be immediately considered for a bone marrow biopsy as chemotherapy should be initiated as soon as possible. Conclusions: See Table. [Table: see text] No significant financial relationships to disclose.