How do you manage iron saturation?

Management of Iron Saturation

Regular monitoring of iron saturation through transferrin saturation and serum ferritin levels is essential for proper management, with treatment decisions based on underlying cause and clinical context. 1

Assessment of Iron Status

• Comprehensive evaluation of iron status should include plasma iron, transferrin, transferrin saturation, ferritin, CRP, hepcidin, and evaluation of red blood cell morphology 1
• Transferrin saturation below 16% in adults often confirms iron deficiency, with a specificity of 93% for iron deficiency defined by absence of bone marrow iron 1
• Serum ferritin is the most specific indicator of depleted iron stores, with levels ≤15 μg/L confirming iron deficiency in anemic patients 1
• For accurate assessment after intravenous iron administration, measure iron status 24-48 hours after iron sucrose or iron gluconate doses, and 1-2 weeks after iron dextran doses 1

Management of Low Iron Saturation

Oral Iron Therapy

• First-line therapy for most patients with iron deficiency is oral iron supplementation (typically ferrous sulfate 325 mg daily or on alternate days) 2, 3
• Alternate-day dosing may improve absorption by allowing hepcidin levels to return to baseline between doses 3, 4
• Avoid vitamin C supplements in patients with hemochromatosis as they can enhance iron absorption 1

Intravenous Iron Therapy

• Intravenous iron is indicated for patients with:
  • Oral iron intolerance or poor absorption (celiac disease, post-bariatric surgery) 2, 4
  • Chronic inflammatory conditions (CKD, heart failure, IBD, cancer) 2, 1
  • Ongoing blood loss 2, 5
  • During second and third trimesters of pregnancy 2
• In CKD patients with low transferrin saturation (<25%) but elevated ferritin (500-1200 ng/ml), intravenous iron can still improve hemoglobin levels 1
• Use caution with intravenous iron in patients with active infection 1
• For rapid replacement, newer carbohydrate-bound iron formulations (carboxymaltose, ferumoxytol, isomaltoside) allow administration of large single doses with lower risk of adverse reactions 1

Management of Iron Overload

Hereditary Hemochromatosis

• All patients with hereditary hemochromatosis who have evidence of iron overload should undergo regular phlebotomies until iron stores are depleted 1
• Maintenance phlebotomy should be continued for life, with frequency determined by serum ferritin levels 1
• Patients with cirrhosis due to hemochromatosis should undergo regular screening for hepatocellular carcinoma 1

Secondary Iron Overload

• Treatment should be tailored to the underlying cause 1
• Phlebotomy is effective for certain forms of secondary iron overload, including African iron overload and porphyria cutanea tarda 1
• Iron chelation therapy with parenteral deferoxamine is the treatment of choice for secondary iron overload associated with ineffective erythropoiesis (e.g., thalassemia) 1
• In hemochromatosis and other iron overload conditions, iron stores should be reduced by repeated venesection 1

Monitoring Recommendations

• In patients requiring iron and/or ESA therapy, measure serum ferritin and transferrin saturation every 1-3 months depending on clinical status 1
• In stable patients with mild anemia not receiving iron or ESA therapy, assessment can be performed yearly 1
• More frequent monitoring is required in clinical situations such as bleeding, surgery, initiation of iron therapy, or rapid change in hemoglobin 1
• To measure success of iron treatment, basic blood tests should be repeated after 8-10 weeks, not earlier after iron infusion as ferritin levels are falsely elevated 1
• If serum ferritin falls below 1000 μg/L at two consecutive visits, consider dose reduction of iron chelation therapy 6
• If serum ferritin falls below 500 μg/L, interrupt iron chelation therapy and continue monthly monitoring 6

Special Considerations

• Use caution with iron therapy in areas endemic for malaria and other infections to avoid worsening infection 4
• Monitor elderly patients more frequently for toxicity with iron chelation therapy 6
• In pediatric patients, higher rates of renal adverse events have been observed with higher doses of iron chelation therapy 6
• Avoid iron chelation therapy in patients with platelet counts below 50 x 10^9/L due to risk of bone marrow suppression 6
• For patients with eGFR 40-60 mL/min/1.73 m², reduce starting dose of iron chelation therapy by 50% 6