A unique blood test detects iron deficiency in infants earlier and more accurately than the commonly used hemoglobin screening test, according to a study in the August 24/31 issue of the Journal of the American Medical Association.
Iron deficiency is estimated to affect nearly 10 percent of American children one to two years of age. Early detection and treatment are critical because iron deficiency can impair infant mental development, possibly permanently, even before it progresses to anemia (clinically identified as a low hemoglobin level).
The study, done at Children’s Hospital Boston, is the first to compare the test, called CHr, with the standard hemoglobin test as a screen for iron deficiency in infants.
Hemoglobin is the iron-containing, oxygen-carrying molecule in red blood cells; the CHr test measures the hemoglobin content of reticulocytes, or immature red blood cells, whereas the standard hemoglobin test is based on the entire population of red blood cells. Because reticulocytes are present in the bloodstream for only 24 to 48 hours, as compared with several months for mature red blood cells, measuring the reticulocyte hemoglobin content (i.e., CHr) provides a more timely indication of iron status, the investigators say.
“There is mounting evidence that iron deficiency in infants can cause permanent neurocognitive deficits, even before it has progressed to the point of causing anemia,” said lead investigator Christina Ullrich, MD, a fellow in pediatric hematology and oncology at Children’s Hospital Boston and the Dana Farber Cancer Institute. “The ability of the CHr test to identify more infants, at an earlier stage of iron deficiency, makes it a better choice for screening than the current hemoglobin test.”
Iron deficiency is the most common nutritional deficiency in the world. Infants and toddlers are especially susceptible because of their rapid growth, increased demands for iron, and variable dietary intake.
The deficiency progresses in three stages:
1) depletion of the body’s iron stores;
2) deficiency, in which hemoglobin synthesis is impaired, resulting in a fall in CHr; and
3) anemia, in which red-blood-cell hemoglobin is below normal for a person’s age.
Iron deficiency is usually readily treated with dietary iron supplementation.
Reference – Medical News Today, JAMA
