From the Guidelines
A fasting iron panel is essential for accurately assessing iron status, and it is recommended to fast for at least 8-12 hours before the blood draw, as food intake can temporarily increase serum iron levels and skew results 1. When evaluating iron status, it is crucial to consider the patient's inflammatory status, as inflammation can affect iron metabolism and lead to inaccurate diagnoses. According to the European evidence-based consensus on the diagnosis and management of ulcerative colitis, in patients without evidence of inflammation, a serum ferritin level < 30 mcg/L or transferrin saturation < 16% defines iron deficiency 1. Key components of the iron panel include:
- Serum iron
- Total iron binding capacity (TIBC)
- Transferrin saturation
- Ferritin levels It is also important to avoid iron supplements for at least 24 hours before testing, as they can artificially elevate results, and to inform healthcare providers about all medications being taken, as certain medications like oral contraceptives or antibiotics may affect results. Morning appointments are preferable, as iron levels naturally fluctuate throughout the day. The complete panel provides a comprehensive picture of iron metabolism, helping to diagnose conditions like anemia, hemochromatosis, or chronic inflammatory disorders that affect iron utilization. In the presence of biochemical evidence of inflammation, the lower limit of ferritin consistent with normal iron stores should be increased to 100 μg/L, and hypoferraemia should be considered likely if TfS is below 16% and serum ferritin is between 30 and 100 g/L 1.
From the Research
Fasting Iron Panel
- Fasting iron panel is not directly mentioned in the provided studies, however, iron deficiency and its treatment are discussed in detail 2, 3, 4, 5, 6.
- Iron deficiency is a common cause of morbidity and can arise as a consequence or complication from many diseases 2.
- The diagnosis of iron deficiency is typically made by measuring serum ferritin and transferrin saturation levels 4.
- Treatment for iron deficiency usually involves oral iron supplementation, but intravenous iron therapy may be necessary for patients with intolerance or unresponsiveness to oral iron 3, 4, 5, 6.
- Intravenous iron preparations can facilitate rapid iron repletion in one or two doses, both for absolute iron deficiency and functional iron deficiency 2.
- The choice between oral and intravenous iron therapy depends on various factors, including the presence of inflammation, the time available for iron replenishment, and the anticipated risk of side-effects or intolerance 2, 4, 5.
Iron Deficiency Treatment
- Oral iron supplementation is usually the first line of treatment for iron deficiency, but it can cause gastrointestinal side effects that reduce compliance 3, 4.
- Intravenous iron therapy is indicated for patients with oral iron intolerance, poor absorption, chronic inflammatory conditions, ongoing blood loss, and during the second and third trimesters of pregnancy 4, 5, 6.
- Modern intravenous iron preparations are associated with a risk of severe infusion reactions, but the risk is comparable among all preparations and affects less than 1% of patients 5.
- The main treatment target for intravenous iron is an improvement of the quality of life, for which hemoglobin is a surrogate marker 5.
Comparison of Oral and Intravenous Iron Therapy
- A study comparing the efficacy and safety of intravenous iron therapy with oral iron supplements in iron deficiency anemia found that intravenous iron therapy was effective and safe for management of iron deficiency anemia 6.
- The study found that hemoglobin and serum ferritin levels increased significantly in both groups, but the increase was more rapid in the intravenous iron group 6.
- Adverse effects were observed in both groups, but the most common side effects in the oral iron group were metallic taste, constipation, heartburn, and nausea, while arthralgia was the major side effect observed in the intravenous iron group 6.