NEW YORK, Jun 15 (Reuters Health) -- An alternate blood screening technique can detect childhood iron deficiency earlier than tests traditionally used in adults. Wider use of the test could prevent many of the illnesses and developmental problems associated with low iron levels in children, researchers suggest.
Dr. Carlo Brugnara of The Children's Hospital, Harvard Medical School in Boston, Massachusetts, and colleagues call early recognition of iron deficiency "crucial" if complications of iron deficiency in childhood are to be prevented.
Although recent nutrition education efforts have greatly reduced the incidence of iron deficiency among US children, a significant amount of cases continue to occur. Children require adequate iron stores for normal physical and intellectual development.
But the standard tests used to spot iron deficiency usually detect the problem only after it has reached the critical stage of anemia -- at which point damage linked to inadequate iron stores may have already occurred.
A number of alternative blood tests may help detect iron deficiency at a much earlier stage. The investigators compared the accuracy of a number of these tests in a sample of 210 children.
They found that one such test -- measuring levels of iron in reticulocytes (developing, immature red blood cells) -- "was the strongest predictor of iron deficiency and iron deficiency anemia in children." In fact, 'reticulocyte hemoglobin' testing consistently outperformed traditional adult blood iron-store tests, which appeared to have "little or no diagnostic value in children," according to the authors.
Brugnara and colleagues believe that the widespread adoption of reticulocyte testing might save the US health industry nearly $80 million each year. In their report, published in the June 16th issue of The Journal of the American Medical Association, they point out that the average battery of iron deficiency tests now cost about $154 per patient "based on typical (US) fees." In contrast, diagnosis involving standard blood cell counts and reticulocyte testing cost just $40 per patient, according to the authors.
The research team also notes that in contrast to the larger amounts of blood required for traditional testing, the reticulocyte test requires only the small amount of blood obtained via a fingerstick.
In an editorial, hematologist Dr. Alan R. Cohen of the University of Pennsylvania School of Medicine in Philadelphia, notes that the study is preliminary, and that improvements must still be made in the accuracy of reticulocyte testing.
He also writes that it is still unconfirmed "that adverse effects of iron deficiency, particularly those involving the brain, begin before anemia develops."
Cohen believes that public health initiatives aimed at improving childhood nutrition may be the best way to fight childhood iron deficiency.
"Better tactics rather than more sophisticated weaponry ultimately may be the key to eradication of childhood iron deficiency," he concludes.
SOURCE: The Journal of the American Medical Association 1999;281:2225-2230, 2247-2248.
