Laboratory Evaluation for Suspected Thrombotic Thrombocytopenic Purpura (TTP)

Essential Immediate Laboratory Tests

• The American Society of Hematology recommends a peripheral blood smear to show schistocytes, which distinguishes TTP from immune thrombocytopenic purpura 1

Secondary Laboratory Tests to Exclude Mimics

• Coagulation studies, including PT, aPTT, fibrinogen, and D-dimer, should be obtained to exclude disseminated intravascular coagulation (DIC), and are typically normal in TTP, as suggested by the American College of Physicians 2