Celiac disease is an autoimmune disorder of the gastrointestinal tract that results from exposure to gluten, a protein present in grains such as barley, rye, and wheat. It is present in about 1% of the United States population, and is most common in people of European descent, while also seen in those from India, the Middle East, and South America (Asians are less affected). Celiac disease is more common in women, those with a family history, and in patients with other autoimmune disorders, like diabetes and thyroid disease. It results from the body’s inability to digest gliadin, a protein present in gluten, which causes an autoimmune inflammatory response in the body’s small intestine. This results in the malabsorption of several key vitamins and nutrients, causing the gastrointestinal symptoms that are the hallmark of the disorder, in addition to protean manifestations in other organ systems.
While most people associate celiac disease with the classic symptoms of diarrhea, bloating, and crampy abdominal pain, more people actually present with extra-intestinal manifestations. These can include anemia, skin lesions, elevated liver tests, neurologic symptoms such as neuropathy, seizures, or headache, osteoporosis, and an increased risk of certain malignancies, such as lymphoma. The diagnosis can be made at any time in life, though with an increased public and medical awareness, it is being found earlier in a patient’s course than ever. Many patients who were told they had irritable bowel syndrome their entire lives have recently been diagnosed with celiac disease. Despite this, however, many patients still remain undiagnosed.
A positive diagnosis of celiac disease can be strongly suggested by blood testing for tissue transglutaminase (TTG) or anti-endomysial antibodies, and confirmed by biopsy of the small intestine during an upper endoscopy. While these blood tests can be quite sensitive and specific, they are not perfect in confirming the diagnosis of celiac disease. Many people are falsely given this diagnosis based solely on weakly positive antibody results, and these people may suffer adverse consequences from an improper diagnosis. As a result, gastroenterologists should be involved in the care of patients in whom the diagnosis of celiac is not certain. There are also blood genetic tests that can be helpful in establishing the diagnosis or determining the risk of family members. Patients with gastrointestinal symptoms seemingly caused by gluten but who test negative for celiac disease may have gluten sensitivity, a newly recognized disorder even more common than celiac disease. These patients respond very well to a gluten-free diet. It is becoming more and more common for people to start gluten-free diets without seeking advice from medical personnel as many simply “feel better” by avoiding gluten
The cornerstone of treatment for celiac disease is a gluten-free diet. While restrictive, it has gotten easier and easier over the last several years for this diet to be maintained. This is largely due to an increasing public awareness of celiac disease, and has resulted in large numbers of gluten-free choices at many supermarkets and restaurants. Studies show the huge majority of patients will have good responses initially to a gluten-free diet, with resolution of their symptoms and improvement in their bloodwork and biopsies. However, a subset of patients will note persistent or recurrent symptoms months to years after the initial diagnosis. The main cause is persistent gluten ingestion, either to noncompliance with a gluten-free diet (which can be increasingly difficult for people to maintain over a long period of time) or to inadvertent continued exposure to gluten.
Other possibilities for the etiology of persistent gastrointestinal symptoms include other concomitant diagnoses, such as irritable bowel syndrome, lactose intolerance, and fructose intolerance. There is a small subset of patients with celiac disease who remain symptomatic despite strict adherence to a gluten-free diet. These patients may require medications like oral steroids or other medications that affect the immune system.
New options may soon be available for treatment of celiac disease, both in the refractory patient and in those experiencing difficulty maintaining a gluten-free diet. Research on medications to treat celiac disease has expanded recently, and there are a number of trials being conducted with a wide variety of molecules aimed at disrupting different stages of the pathogenesis of celiac disease. Exciting and promising areas of investigation include medications designed to degrade gluten into substances that will not elicit the autoimmune inflammatory response that results in symptoms, and other medications designed to prevent specific steps of this inflammatory response. While these trials are only in the early stages, results thus far are very promising and there is hope that within several years, celiac patients may have options for treatment in addition to a gluten-free diet.
There is an increasing awareness of celiac disease and gluten sensitivity and while these conditions are being found more often, many patients still go undiagnosed. There are other people who are incorrectly given the diagnosis of celiac disease. While many people feel better with less abdominal discomfort and bloating on a gluten-free diet, it is still important to seek the care of a gastroenterologist to confirm the diagnosis. Most people with celiac disease respond well to a gluten-free diet, which has become easier (though still difficult) to maintain as an increased public knowledge has resulted in an exponential increase in the availability of gluten-free options. Promising trials are underway that explore alternative therapies to a gluten-free diet for patients with celiac disease.
Dr. Purow is a member of the American College of Gastroenterology and the American Gastroenterology Associations. He maintains an avid interest in all areas of gastroenterology and liver disease, and is currently serving as the Chief of the Division of Internal Medicine at Huntington Hospital. He can be reached at his office, North Country Medical Associates, located at 195 East Main Street, Huntington, New York 11743. Call 631-549-8181 or visit www.northcountrymedassoc.com for more info.