Hemolytic anemia can be caused by several conditions with different mechanisms.
Intrinsic red cell defect:
(1) abnormal red cell membrane (spherocytosis, ovalocytosis, elliptocytosis, stomatocytosis, pyropoikilocytosis)
(2) enzymopathy (G6PD deficiency, pyruvate kinase, other)
(3) hemoglobinopathy (hemoglobin C, other)
(4) paroxysmal nocturnal hemoglobinuria (PNH)
Extrinsic cause:
(1) immune-mediated
(1a) autoimmune
(1b) alloimmune
(2) mechanical
(2a) microthrombotic: DIC, HUS, vasculitis, TTP
(2b) heart valves and prosthetic materials
(2c) burns
(2d) disseminated cancer
(3) osmotic (drowning, water infusion)
(4) toxic (snake, drug, other)
(5) infectious disease (clostridial toxin, leptospirosis, other)
