From the Guidelines
Administering IV iron to a patient with influenza pneumonia and chronic iron deficiency anemia is not recommended during the acute infectious phase, and it's best to delay IV iron therapy until the patient has recovered from the acute infection. This approach is based on the potential risks associated with IV iron administration during an active infection, as highlighted in a systematic review and meta-analysis published in JAMA Network Open 1. The review found that intravenous iron was associated with an increased risk of infection, which must be considered alongside the potential benefit of treating anemia.
Given the uncertainty about the risk of infection, it is prudent to prioritize treating the influenza pneumonia with appropriate antiviral medications (such as oseltamivir if within 48 hours of symptom onset) and supportive care. Once the patient has clinically improved and the acute infection has resolved, IV iron therapy can be safely initiated to address the chronic iron deficiency anemia. Common IV iron preparations include iron sucrose (typically 200-300mg per dose), ferric carboxymaltose, or iron dextran, with specific dosing based on the patient's hemoglobin level and body weight.
The most recent expert consensus guidelines on intravenous iron uses, formulations, administration, and management of reactions, published in the American Journal of Hematology in 2024 1, provide comprehensive guidance on the safe delivery of intravenous iron. Additionally, the AGA clinical practice update on management of iron deficiency anemia, published in Clinical Gastroenterology and Hepatology in 2024 1, recommends using IV iron if the patient does not tolerate oral iron, ferritin levels do not improve with a trial of oral iron, or the patient has a condition in which oral iron is not likely to be absorbed. However, in the context of an active infection like influenza pneumonia, the potential benefits of IV iron must be weighed against the potential risks, and delaying therapy until the infection has resolved is the most prudent approach.
From the Research
Safety of IV Iron in Influenza Pneumonia with Chronic Iron Deficiency Anemia
- The safety of administering IV iron to a patient with influenza pneumonia and concurrent chronic iron deficiency anemia can be considered based on several studies 2, 3, 4, 5, 6.
- According to a study published in 2020, intravenous iron supplementation therapy is generally safe, with modern iron formulations having a low risk of severe infusion reactions, affecting less than 1% of patients 3.
- Another study from 2020 discusses the efficacy and safety of high-dose intravenous iron as the first-choice therapy in outpatients with severe iron deficiency anemia, showing that it is effective and safe for quick correction and avoidance of red blood cell transfusion 6.
- However, it is essential to note that patients with inflammation, such as those with influenza pneumonia, may have altered iron metabolism, and iron deficiency should be suspected as an anemia cause when transferrin saturation is low, even if serum ferritin is normal 3.
- A study from 2010 highlights the importance of individual selection of the appropriate iron therapy and evaluation of treatment response to safely deliver improved outcomes through intravenous iron therapies 4.
- Additionally, a 2005 study found that immune-associated functional iron deficiency is common in critically ill patients and may benefit from IV iron therapy, which could help ameliorate their inflammatory status 5.
- When considering IV iron therapy, it is crucial to weigh the potential benefits against the risks, including the possibility of hypophosphatemia, a complication that can occur with certain IV iron formulations 3.