What are the normal ranges, causes of abnormalities, and treatment recommendations for serum iron, ferritin, transferrin, transferrin saturation, and Total Iron-Binding Capacity (TIBC)?

From the Guidelines

Iron deficiency anemia should be treated with intravenous iron as first-line treatment in patients with clinically active inflammatory bowel disease (IBD), previous intolerance to oral iron, hemoglobin below 100 g/L, and in patients who need erythropoiesis-stimulating agents, while oral iron may be used in patients with mild anemia and clinically inactive disease. The following chart summarizes the key markers for assessing iron status in the body:

• Normal serum iron: 60-170 μg/dL in men and 50-130 μg/dL in women
• Normal ferritin: 20-250 ng/mL in men and 10-120 ng/mL in women
• Normal transferrin: 200-360 mg/dL
• Normal transferrin saturation: 20-50%
• Normal total iron binding capacity (TIBC): 250-450 μg/dL Causes for high or low levels of these markers include:
• Low iron levels: iron deficiency anemia, blood loss, malnutrition, or chronic inflammation
• High iron levels: hemochromatosis, hemolysis, or excessive supplementation Treatment recommendations are as follows:
• Iron deficiency: oral iron supplements (ferrous sulfate 325 mg 1-3 times daily) or intravenous iron for severe cases, with monitoring of iron status and adjustments based on clinical response and laboratory values 1
• Iron overload: therapeutic phlebotomy and iron chelation therapy with medications like deferasirox, with addressing underlying causes being essential in both scenarios In patients with IBD, iron supplementation is recommended when iron-deficiency anemia is present, with quality of life improving with the correction of anemia, independent of clinical activity 1. After successful treatment of iron deficiency anemia with intravenous iron, re-treatment with intravenous iron should be initiated as soon as serum ferritin drops below 100 mg/L or hemoglobin below 120 or 130 g/L according to gender 1.

From the Research

Iron, Ferritin, Transferrin, Transferrin Saturation, and TIBC: Normals, Causes, and Treatment

• Normals: + Iron: 50-170 μg/dL 2 + Ferritin: 30-400 ng/mL 2, 3 + Transferrin: 200-400 mg/dL 4 + Transferrin Saturation (TSAT): 20-50% 2, 3 + TIBC (Total Iron-Binding Capacity): 240-450 μg/dL 4
• Causes for High or Low Levels: + Iron deficiency: absolute (severely reduced or absent iron stores) or functional (adequate iron stores but insufficient iron availability) 2 + Anemia of chronic disease: reduced iron availability due to increased hepcidin levels 2 + Chronic kidney disease (CKD): iron deficiency, anemia, and impaired cellular function 5, 2 + Heart failure: iron deficiency, defined by TSAT <20% and serum ferritin level <400 μg/L 3
• Treatment Recommendations: + Iron supplementation: recommended for all CKD patients with anemia 5, 2 + Intravenous iron: preferred route of administration in hemodialysis patients, and recommended for CKD patients on dialysis (CKD stage 5D) 5, 2 + Oral iron: recommended for patients with CKD ND (CKD stages 3-5) 2 + Erythropoiesis-stimulating agents (ESAs): may be used in combination with iron therapy for anemia management 6, 2 + Blood transfusion: not recommended for chronic anemia, as it does not address the underlying disorder 6