HP and congenital thrombotic thrombocytopenic purpura: Microangiopathic hemolytic anemia is diagnosed when there are signs of anemia and hemolysis, such as schistocytes in a blood smear, increased lactate dehydrogenase, serum free hemoglobin, reticulocytosis, and diminished haptoglobin which may be a delicate, but nonspecific feature [9].