New Lab Test Catches Anemia Markers Early.
SCOTTSDALE, ARIZ. -- The "hottest new thing" on lab slips for a complete blood count is the reticulocyte hemoglobin content, which will allow physicians to spot iron deficiency well before a child becomes seriously anemic, Dr. James A. Stockman III, said at a pediatric update sponsored by Phoenix (Ariz.) Children's Hospital.
"I dare say your labs don't have this technique yet, but they will," said Dr. Stockman, president of the American Board of Pediatrics and clinical professor of pediatrics at Duke University in Durham, N.C., and the University of North Carolina at Chapel Hill.
It takes 3 months of iron deficiency to produce an abnormal red blood cell count. Problems plague use of other potential markers of iron deficiency, with only a combination of mean corpuscular volume and red cell distribution width on a full elective printout achieving a good positive predictive value, Dr. Stockman commented.
Reticulocytes are the first cells produced in circulation and reflect iron levels within 72 hours of when a blood panel is drawn.
"They are a very, very early marker of iron deficiency, [sometimes] detecting it before a child is anemic," Dr. Stockman further noted.
A normal range for reticulocyte hemoglobin content (RHc) is 25.6-29.6. Iron deficiency anemia results in an RHc level of 19.2 +/-2.04.
If an RHc level comes back [less than]20, there is a 90% probability the child has iron deficiency anemia.
An RHc level [less than]24 confers a 50% likelihood that a child has iron deficiency anemia.
An RHc level [greater than]29 means there is no chance the child is experiencing a deficiency of iron.
Renal dialysis patients have slightly different values, with an RHc level [less than]26 predicting iron deficiency with 100% sensitivity and 80% specificity.
Iron deficiency affects only 3% of American children today. Those most at risk include breast-fed babies who do not receive iron supplementation; children with frequent minor illnesses between 6 months and 2 years of age; infants and children who consume large quantities of milk; and female adolescent athietes, who have the highest prevalence of iron deficiency of any age group in the United States.
Mild illnesses are also linked to iron deficiency because inflammation interferes with absorption of iron. For example, a child who experiences three episodes of otitis media in a year will also accumulate 3 months of poor iron absorption, Dr. Stockman explained.
|Printer friendly Cite/link Email Feedback|
|Comment:||New Lab Test Catches Anemia Markers Early.|
|Publication:||Family Practice News|
|Article Type:||Brief Article|
|Date:||Jul 15, 2001|
|Previous Article:||BLOOD PRODUCTS.|
|Next Article:||Passive Smoke Tied To Cavities.|