What are the optimal ranges for iron studies, including serum iron, total iron-binding capacity (TIBC), and transferrin saturation?

From the Guidelines

Optimal iron studies ranges include serum ferritin between 100-300 ng/mL and transferrin saturation between 20-50%. These ranges help identify iron deficiency, which is diagnosed when ferritin falls below 100 ng/mL and transferrin saturation below 20% 1.

Key Points

• The goal of iron therapy is to improve erythropoiesis, not to attain specific levels of TSAT and/or serum ferritin 1.
• The distinction between absolute and functional iron deficiency is crucial to understanding what constitutes adequate TSAT and serum ferritin levels in Epoetin-treated patients 1.
• In the presence of inflammation, a serum ferritin up to 100 mg/L may still be consistent with iron deficiency 1.
• Iron supplementation is recommended in all patients with iron-deficiency anemia, and intravenous iron should be considered as first-line treatment in patients with clinically active disease or previous intolerance to oral iron 1.
• Regular monitoring of iron status is essential for patients with chronic conditions affecting iron metabolism, such as chronic kidney disease or inflammatory disorders, as inflammation can artificially elevate ferritin levels 1.

Monitoring and Treatment

• Iron status should be assessed as part of the initial evaluation of anemia in all patients with CKD, and measurement of serum ferritin and transferrin saturation every 1–3 months is reasonable in patients who require iron and/or ESA therapy 1.
• In patients receiving intravenous iron, an accurate assessment of iron status may require a delay between the last iron infusion and the measurement of iron status 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

Optimal Iron Studies Ranges

The optimal iron studies ranges are not explicitly stated in the provided studies. However, the studies provide information on the effects of different iron supplements on iron deficiency anemia.

• The study 2 found that iron from iron-enriched Aspergillus oryzae was absorbed similarly to ferrous sulfate, but with fewer gastrointestinal side effects.
• The study 3 discusses the use of intravenous iron supplementation therapy, which is reserved for iron deficiency anemia patients with intolerance or unresponsiveness to oral iron.
• The study 4 discusses the treatment strategy and tactics for iron deficiency anemia, including the use of ferrous sulfate and its side effects.
• The study 5 found that lactoferrin supplementation had better effects on serum iron, ferritin, and hemoglobin concentration compared to ferrous sulfate, but with a reducing effect on fractional iron absorption.

Key Findings

• Serum iron, percentage transferrin saturation, and non-transferrin-bound iron were measured in the study 2 to assess the safety of consuming iron-enriched Aspergillus oryzae.
• The study 3 mentions that the main treatment target for intravenous iron is an improvement of the quality of life, for which hemoglobin is a surrogate marker.
• The study 5 found that lactoferrin supplementation had a reducing effect on IL-6 levels, which may be related to its anti-inflammation effect.

Iron Supplementation

• Ferrous sulfate is a commonly used iron supplement, but it can have gastrointestinal side effects 2, 4, 5.
• Lactoferrin is a potential alternative to ferrous sulfate, with fewer side effects and better effects on serum iron and hemoglobin concentration 5.
• Intravenous iron supplementation therapy is reserved for iron deficiency anemia patients with intolerance or unresponsiveness to oral iron 3.