Abstract & Commentary
Synopsis: An NIH Consensus Panel has announced new recommendations for the diagnosis of celiac disease using new serologic testing. This disorder is easily treated, but the diagnosis may be delayed for many years due to the nonspecific nature of the symptoms. Celiac disease has a frequency that is 10 times previous estimates.
Source: Mitka M. JAMA. 2004;292:913-914.
Celiac disease is an immune-mediated disorder with chronic inflammation of the small intestinal mucosa resulting in atrophy of intestinal villi and malabsorption. Symptoms include diarrhea, abdominal cramping, pain and distention, very similar to irritable bowel syndrome. Once considered to a rare condition, celiac disease affects about 1% of the US population and may manifest in childhood or as adults. The average delay in diagnosis is 10 years!
Celiac disease should be considered in any patient with chronic GI symptoms described above. New serologic tests which have a high sensitivity and specificity are: antihuman tissue transglutaminase IgA and endomysial antibody immunofluorescence IgA. Confirmation of positive testing may be done by biopsy of the proximal small bowel. Definitive diagnosis comes from a resolution of symptoms when the patient is placed on a gluten-free diet.
Gluten is a dietary protein present in wheat, barley and rye. Patients and their family may want to consult a dietician for specifics on the necessary dietary changes, or consult various internet sources. The main substitution rice based grains for those above, and rice breads and other products have become widely available.
The NIH consensus statement is available at: http://consensus.nih.gov/cons/118/118cdc_intro.htm.
Comment by Joseph E. Scherger, MD, MPH
Not mentioned in this article is the frequency of celiac disease in the elderly, which may be a variant of the autoimmune disorder. My introduction to this phenomenon was my father, who during his 70s developed diarrhea, bloating, and gas, which completely resolved on a gluten free diet. He is doing well at 87. Since then I have had a series of elderly patients develop the same condition and they are grateful for the diagnosis and treatment which allows them to remain socially active. These GI complaints are embarrassing and may limit eating out and other social activities. Information about gluten-free diets has become common among seniors. While the development of an autoimmune condition may be possible, I have explained to patients that certain enzyme systems atrophy or wear out with age. We certainly know this to be true with lactose intolerance, which worsens with age.
This NIH consensus statement states that while the definitive diagnosis comes from a trial of a gluten free diet, endoscopy with biopsies of the proximal small intestine should be done after serologic testing. Despite the certainty that comes from a tissue diagnosis, I doubt that most primary care physicians will feel that invasive testing is necessary when the history, serologic testing and a dietary challenge all point to the diagnosis. Most importantly, think of celiac disease in patients with chronic diarrhea, bloating, pain, and gas.
Dr. Scherger, Clinical Professor, University of California, San Diego, is Associate Editor of Internal Medicine Alert.