May 20, 2008 -- Most Americans who have celiac disease probably don't know it.
A new study shows that the criteria used to diagnose the disorder may be too stringent, leaving many people undiagnosed and untreated.
It is estimated that one in every 100 Americans may be affected by celiac disease. But "only 5% of these people have ever been diagnosed," says Peter H. Green, MD, professor of clinical medicine at Columbia University Medical School in New York City.
Green moderated a news briefing to discuss the new research at Digestive Disease Week 2008 in San Diego.
When people with celiac disease eat foods containing gluten, their immune system attacks the protein. This damages the intestinal lining, hampering the ability to absorb vital nutrients from food and eventually leading to malnutrition.
Currently, a biopsy of the small intestine is considered the gold standard for diagnosing celiac disease, Green says. Doctors look for damage of the villi -- little finger-like protrusions in the small intestine important for absorbing nutrients.
The biopsy is typically given if blood tests show you have certain antibodies that are associated with celiac disease.
Biopsy May Miss Celiac Disease
The new study involved 145 patients suspected of having celiac disease. Of those, 71 were positive on the antibody blood test. Of those, 48 met the criteria for celiac disease on biopsy.
The remaining 23 patients were divided randomly into two groups. One group was placed on a gluten-free diet, and the other continued eating a regular diet that included gluten.
After one year, patients on the gluten-free diet were free of symptoms.
But symptoms worsened in people who continued to eat the regular diet. And their intestinal linings showed signs of inflammation and deterioration.