microangiopathic hemolytic anemiaalloimmune hemolytic anemiaautoimmune hemolytic anemia causescongenital hemolytic anemiahereditary hemolytic anemiainherited hemolytic anemiaacquired hemolytic anemiachronic hemolytic anemiahemolytic anemia definitionimmune hemolytic anemiaacute hemolytic anemiahemolytic anemia in dogs