New Progress Being Made in Celiac Diagnosis

As many readers know, celiac disease (a genetic intolerance to gluten, a protein found in wheat, rye and barley, which triggers this destructive reaction to the small intestine, which can lead to malabsorption of nutrients and glycemic instability) is especially common among people with type 1 diabetes because both are believed to be autoimmune diseases. Unfortunately, obtaining a diagnosis of celiac disease is often an exercise in frustration, in part, because there often aren't overt symptoms, and the tools used in diagnosis aren't always 100% accurate. In fact, a diagnosis is often only made by using a process of elimination.

According to the Celiac Disease Center at Columbia University, the current "gold standard" for diagnosis is the small intestinal biopsy, done during a procedure called endoscopy. The diagnosis is based on finding a series of abnormalities in an intestinal biopsy (increased inflammation and villous atrophy) that return toward normal on a gluten-free diet. This means adherence to a gluten-free diet may be required in order to diagnose patients. A follow up biopsy is not always necessary or even performed, but the combination of an abnormal biopsy and improvement of symptoms after gluten is eliminated from the diet is usually enough to establish a diagnosis. Blood tests that indicate higher-than-normal levels of specific antibodies may also be used to support the diagnosis, but positive antibodies are not required to make the diagnosis, and many doctors fail to order these tests.

For this reason, an article published in Reuters late yesterday (one of those you might miss otherwise) may bring some good news. Apparently, scientists in Italy have pioneered a method that improves the accuracy and speed of diagnosis significantly using what is sometimes called a "pill camera", officially known as video capsule enteroscopy or VCE. Read the Reuters article here:

Video capsule may soon diagnose celiac disease

NEW YORK (Reuters Health) - A new device -- video capsule enteroscopy (VCE) -- accurately detects intestinal atrophy in patients suspected to have celiac disease, according to a report in the American Journal of Gastroenterology.

The diagnosis of celiac disease currently requires upper GI endoscopy with multiple biopsies to identify the characteristic irregularities in the mucus tissue of the small bowel, the authors explain. GI endoscopy is a procedure in which a tube is inserted into the digestive tract. The tube is equipped with a small camera to visualize abnormal tissues, which can be biopsied or removed.

Celiac disease is a genetic disorder in which the body's immune system damages the small intestine in responses to foods containing gluten, a protein in wheat, rye and barley. Celiac disease may cause a variety of symptoms. Diarrhea, abdominal pain, irritability and depression are common, but some people may have no symptoms. Treatment for the condition is a gluten-free diet.

Dr. Roberto de Franchis from the University of Milan, Italy and associates tested the performance of VCE in 43 patients with signs or symptoms suggestive of celiac disease and compared the results to those obtained by conventional upper GI endoscopy with biopsies.

Of 32 patients found to have abnormal tissue, 28 were diagnosed with celiac disease by capsule endoscopy, yielding a sensitivity of 87.5%.

VCE had 90.9% specificity, 96.5% positive predictive value, 71.4% negative predictive value for diagnosing celiac disease.

"The recently introduced VCE may be a valid alternative to...biopsy in this patient population, since it provides high-quality images of the small bowel mucosa," the investigators conclude. "Furthermore, it is minimally invasive, which may improve patient acceptance, and it allows exploration of the whole small intestine, which may lead to the identification of (abnormal tissue) beyond the segments reached by upper GI endoscopy."

They add that the findings "await confirmation in a larger study."

SOURCE: Reuters Health, August 20, 2007 and the American Journal of Gastroenterology, August 2007.

Photo: The Given® video endoscopy capsule, courtesy of the New South Wales (Australia) Government Health Service.