Mechanism |
Examples |
Chronic excessive bleeding |
Cancer in the digestive tract Ulcers in the stomach or small intestine |
Sudden excessive bleeding |
Injuries A ruptured blood vessel Surgery |
Decreased red blood cell production |
Metastatic cancer Myelodysplasia (abnormalities in bone marrow tissue) |
Increased red blood cell destruction |
Autoimmune reactions against red blood cells Glucose-6-phosphate dehydrogenase (G6PD) deficiency Hereditary elliptocytosis Hereditary spherocytosis Hereditary stomatocytosis Hereditary xerocytosis Mechanical damage to red blood cells Paroxysmal nocturnal hemoglobinuria |