Main causes of absolute iron deficiency/iron deficiency anemia
| Type of cause . | Condition . | Pathophysiologic mechanism . |
|---|---|---|
| Increased iron requirements | Infants, preschool children, adolescents | Rapid growth |
| Pregnant women: second and third trimesters | Expansion of maternal and fetal erythroid mass | |
| ESA treatment | Acute expansion of erythroid mass | |
| Low iron intake | Malnutrition* | Insufficient dietary iron: low heme iron or scarcely bioavailable iron (eg, chelated by phytates) |
| Vegetarians, vegans | ||
| Decreased intestinal iron absorption | Gastrectomy, duodenal bypass, bariatric surgery | Decreased absorptive surface |
| Gluten-induced enteropathy | ||
| Autoimmune atrophic gastritis | Increased pH | |
| Helicobacter pylori infection | Increased pH and blood loss | |
| Drugs: proton pump inhibitors, H2 blockers | Blocking of gastric acid secretion | |
| Genetic IRIDA† | High serum hepcidin levels | |
| Chronic blood loss | Hookworm infestation* | Bleeding from gastrointestinal tract |
| Gastrointestinal benign and malignant lesions | ||
| Salicylates, corticosteroids, nonsteroidal anti-inflammatory drugs | ||
| Heavy menses, hematuria | Bleeding from genitourinary system | |
| Intravascular hemolysis (PNH, march hemoglobinuria) | Urinary loss of hemoglobin (iron) | |
| Drugs: anticoagulants, antiplatelet compounds | Systemic bleeding | |
| Defects of hemostasis (hereditary hemorrhagic telangectasia, von Willebrand disease) | ||
| Frequent blood donors | Repeated blood letting | |
| Multiple causes (absolute iron deficiency associated with inflammation) | Chronic infections in malnutrition* | Reduced intake, increased proinflammatory cytokines |
| Chronic kidney disease | Decreased iron absorption, increased blood loss, reduced hepcidin excretion and increased production, drugs, ESAs | |
| Chronic systolic heart failure | Decreased iron absorption, increased inflammation, blood loss | |
| Inflammatory bowel diseases | Decreased iron absorption, increased blood loss, high hepcidin | |
| Postoperative anemia of major surgery | Blood loss, increased proinflammatory cytokines |
| Type of cause . | Condition . | Pathophysiologic mechanism . |
|---|---|---|
| Increased iron requirements | Infants, preschool children, adolescents | Rapid growth |
| Pregnant women: second and third trimesters | Expansion of maternal and fetal erythroid mass | |
| ESA treatment | Acute expansion of erythroid mass | |
| Low iron intake | Malnutrition* | Insufficient dietary iron: low heme iron or scarcely bioavailable iron (eg, chelated by phytates) |
| Vegetarians, vegans | ||
| Decreased intestinal iron absorption | Gastrectomy, duodenal bypass, bariatric surgery | Decreased absorptive surface |
| Gluten-induced enteropathy | ||
| Autoimmune atrophic gastritis | Increased pH | |
| Helicobacter pylori infection | Increased pH and blood loss | |
| Drugs: proton pump inhibitors, H2 blockers | Blocking of gastric acid secretion | |
| Genetic IRIDA† | High serum hepcidin levels | |
| Chronic blood loss | Hookworm infestation* | Bleeding from gastrointestinal tract |
| Gastrointestinal benign and malignant lesions | ||
| Salicylates, corticosteroids, nonsteroidal anti-inflammatory drugs | ||
| Heavy menses, hematuria | Bleeding from genitourinary system | |
| Intravascular hemolysis (PNH, march hemoglobinuria) | Urinary loss of hemoglobin (iron) | |
| Drugs: anticoagulants, antiplatelet compounds | Systemic bleeding | |
| Defects of hemostasis (hereditary hemorrhagic telangectasia, von Willebrand disease) | ||
| Frequent blood donors | Repeated blood letting | |
| Multiple causes (absolute iron deficiency associated with inflammation) | Chronic infections in malnutrition* | Reduced intake, increased proinflammatory cytokines |
| Chronic kidney disease | Decreased iron absorption, increased blood loss, reduced hepcidin excretion and increased production, drugs, ESAs | |
| Chronic systolic heart failure | Decreased iron absorption, increased inflammation, blood loss | |
| Inflammatory bowel diseases | Decreased iron absorption, increased blood loss, high hepcidin | |
| Postoperative anemia of major surgery | Blood loss, increased proinflammatory cytokines |