From the Guidelines
Falsely elevated serum iron levels can be caused by several factors, including hemolysis of blood samples, recent blood transfusions, certain medications like iron supplements and antibiotics, acute hepatitis or liver damage, and laboratory errors such as sample contamination. These factors can potentially lead to misdiagnosis or inappropriate treatment, highlighting the importance of accurate interpretation of iron studies. Some key points to consider include:
- Hemolysis of blood samples, which can release iron from damaged red blood cells and artificially increase measured levels 1.
- Recent blood transfusions, which can temporarily elevate serum iron for several weeks.
- Medications that commonly cause falsely elevated readings, such as iron supplements (oral or IV), multivitamins containing iron, and certain antibiotics like chloramphenicol.
- Acute hepatitis or liver damage, which may release stored iron into circulation.
- Laboratory errors, such as sample contamination from iron-containing collection tubes, which can produce falsely high results. It is essential to recognize these potential interferences to properly interpret iron studies and avoid unnecessary interventions, as supported by the most recent and highest quality study 1. Additionally, the timing of blood collection is crucial, as iron levels follow a diurnal pattern with highest values typically occurring in the morning, and patients should temporarily discontinue iron supplements 24-48 hours before testing unless specifically instructed otherwise by their healthcare provider 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Factors that Can Falsely Elevate Serum Iron Levels
- Hemolysis of blood samples, which can lead to the release of iron from red blood cells 2
- Recent iron supplementation or transfusions, which can temporarily increase serum iron levels 3, 4
- Inflammation or liver disease, which can affect the production of transferrin and other proteins that bind to iron, leading to elevated serum iron levels 5
- High-dose vitamin C intake, which can enhance iron absorption in individuals with high iron stores or iron overload 6
Laboratory Considerations
- Hemolysis or contamination of blood samples can falsely elevate serum iron levels 2
- Incorrect measurement or calculation of serum iron levels can lead to inaccurate results 5
Clinical Considerations
- Patients with hemochromatosis or other iron overload disorders may have elevated serum iron levels due to their underlying condition, rather than any external factor 2, 6
- Individuals with anemia or iron deficiency may have low serum iron levels, which can be misinterpreted as falsely elevated if not properly evaluated in the context of their clinical condition 3, 5