What is the required number of intravenous iron infusions for a 79-year-old male with iron deficiency anemia, characterized by a low iron level (Hypoferritinemia), elevated Total Iron-Binding Capacity (TIBC), and low ferritin, who is intolerant to oral iron supplements?

From the Guidelines

For this 79-year-old male with iron deficiency (iron level 49, TIBC 411, ferritin 13.4, hemoglobin 11.9) who cannot tolerate oral iron, I recommend a total of 1000 mg of intravenous iron, typically administered as 1-2 infusions, as formulations that can replace iron deficits with 1 or 2 infusions are preferred 1. The patient's iron deficiency and inability to tolerate oral iron make intravenous iron supplementation the most suitable option.

• The iron deficit calculation can be estimated using the Ganzoni formula, but a simpler scheme with a minimum of 500–1000 mg of intravenous iron can be considered, as seen in the FERGIcor trial 1.
• The specific IV iron formulation could be iron sucrose, ferric carboxymaltose (Injectafer), or iron dextran (INFeD), with the choice depending on the patient's needs and the formulation's characteristics 1.
• After completing the infusions, follow-up labs should be checked in 4-8 weeks to assess response, including hemoglobin, iron studies, and ferritin.
• IV iron is appropriate in this case due to documented iron deficiency with intolerance to oral preparations, and will bypass the gastrointestinal absorption issues while rapidly replenishing iron stores to correct the deficiency 1.

From the FDA Drug Label

For patients weighing 50 kg or more, the recommended dosage is: Injectafer 750 mg intravenously in two doses separated by at least 7 days for a total cumulative dose of 1,500 mg of iron per course In adult patients, Injectafer 15 mg/kg body weight up to a maximum of 1,000 mg intravenously may be administered as a single-dose per course.

To determine the number of iron infusions needed, we need to calculate the patient's weight in kg and the total iron deficit.

• The patient's iron level is 49, TIBC is 411, and ferritin is 13.4.
• The patient's hemoglobin is 11.9, which is below normal.
• The patient weighs 79 years old, but the weight in kg is not provided. We will assume an average weight for a 79-year-old male, which is around 70-80 kg. Let's assume the patient weighs 75 kg.
• The recommended dosage for a patient weighing 50 kg or more is 750 mg intravenously in two doses separated by at least 7 days for a total cumulative dose of 1,500 mg of iron per course.
• Alternatively, the recommended dosage is 15 mg/kg body weight up to a maximum of 1,000 mg intravenously may be administered as a single-dose per course. For a 75 kg patient, the dose would be 15 mg/kg x 75 kg = 1125 mg, which is above the maximum recommended dose of 1000 mg per course. Based on the patient's weight and the recommended dosage, 2 infusions of 750 mg each, separated by at least 7 days, are likely needed 2.

From the Research

Iron Deficiency and Infusion Needs

To determine the number of iron infusions needed for a 79-year-old male with iron deficiency, we need to calculate the total iron deficit.

• The patient's iron level is 49, TIBC is 411, and ferritin is 13.4, indicating iron deficiency.
• The patient's hemoglobin level is 11.9, which is below the normal range.
• According to the study 3, the average iron deficit was calculated to be 1531 mg for patients with iron deficiency anemia.
• The study 3 also suggests that a total cumulative dose of 1000 mg of IV iron may be insufficient for iron repletion in a majority of patients with IDA, and a dose of 1500 mg is closer to the actual iron deficit in these patients.

Calculation of Iron Deficit

• The total iron deficit can be calculated using the Ganzoni formula, which takes into account the patient's weight, hemoglobin level, and iron level.
• However, the exact calculation is not provided in the given studies.
• Based on the study 3, a cumulative dose of 1500 mg of IV iron may be required to correct the iron deficit.

Number of Iron Infusions Needed

• The number of iron infusions needed depends on the specific iron formulation used and the dose administered per infusion.
• According to the study 4, modern iron formulations can be infused at different doses and allow correction of total iron deficit with single or repeated doses in 1-2 weeks.
• The study 5 suggests that intravenous iron preparations can facilitate rapid iron repletion in one or two doses.
• Based on the study 3, a cumulative dose of 1500 mg of IV iron may be administered in one or two infusions, depending on the specific formulation and dose used.