What is the treatment of hemolytic-uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP)?

Plasma exchange.  This will remove antibodies to a von Willebrand factor-cleaving protease (ADAMTS13), deplete very high circulating levels of von Willebrand factor (VWF) multimers, and replace the missing protease (ADAMTS13).   If there is a delay in initiating plasma exchange, give FFP which contains ADAMTS13.

Consider the diagnosis of HUS and/or TTP when there is unexplained thrombocytopenia (typically less than 20K) + microangiopathic hemolytic anemia (MAHA) [schistocytes, normal PT/PTT, elevated LDH, elevated indirect bili, dereased haptoglobin)


Source

Kaplan, A. and George, J.  "Treatment of thrombotic thrombocytopenic purpura and hemolytic uremic syndrome in adults"  Up to Date.  Jan 2013.

Sabatine, M.  Pocket Medicine: The Massachusetts General Hospital Handbook of Internal Medicine.  3rd ed.