Causes of intravascular hemolysis
| Complement fixation (eg) |
| Paroxysmal nocturnal hemoglobinuria |
| Paroxysmal cold hemoglobinuria |
| Acute hemolytic transfusion reactions due to mismatched blood |
| Some autoimmune hemolytic anemias if complement fixation allows terminal complement activation (membrane attack complex formation) on the surface of red blood cells causing lysis |
| Mechanical trauma (eg) |
| Cardiac valves |
| Microthrombi in circulation - DIC, MAHA (TTP, HUS, aHUS) |
| March hemoglobinuria |
| Toxic or exogenous factors (eg) |
| Infections: Babesia, Clostridium, Leptospira, Falciparum malaria |
| Spider bites |
| Snake venoms |
| Copper or zinc toxicity |
| Hypotonic solutions |
| Complement fixation (eg) |
| Paroxysmal nocturnal hemoglobinuria |
| Paroxysmal cold hemoglobinuria |
| Acute hemolytic transfusion reactions due to mismatched blood |
| Some autoimmune hemolytic anemias if complement fixation allows terminal complement activation (membrane attack complex formation) on the surface of red blood cells causing lysis |
| Mechanical trauma (eg) |
| Cardiac valves |
| Microthrombi in circulation - DIC, MAHA (TTP, HUS, aHUS) |
| March hemoglobinuria |
| Toxic or exogenous factors (eg) |
| Infections: Babesia, Clostridium, Leptospira, Falciparum malaria |
| Spider bites |
| Snake venoms |
| Copper or zinc toxicity |
| Hypotonic solutions |
aHUS, atypical hemolytic uremic syndrome; DIC, disseminated intravascular coagulation; HUS, hemolytic uremic syndrome; MAHA, microangiopathic hemolytic anemia; TTP, thrombotic thrombocytopenic purpura.