Celiac Disease More Prevalent in Diabetic Children

As a result of their study published in the Journal of Pediatric Gastroenterology, a group of Medical College of Wisconsin researchers are recommending that children with insulin-dependent diabetes mellitus (IDDM) be tested for celiac disease (CD). In their report on young patients with diabetes, P.C. Lee, PhD, Elaine Parton, RN, CPNP, Steven Werlin, MD and David T. Wyatt, MD concluded that the incidence of celiac disease among American children with IDDM is likely higher than previously thought. The researchers tested diabetic patients at Children's Hospital of Wisconsin for signs and symptoms of celiac disease and found that at least 4.6% of the children who participated in the study suffered from CD, while even more had indicators that could be early signs of the disease. (Atiye N. Aktay, MD, currently practicing in Turkey, and Vijay Kumar, PhD, of the State University of New York, were also members of the research team.)

Celiac disease is a genetic digestive disorder that damages the small intestine and interferes with absorption of nutrients from food. People who have CD cannot tolerate gluten, a protein found in wheat, rye, barley, and possibly oats. When they do eat gluten-containing foods, their immune system responds and damages the lining of the small intestine. The damaged areas can’t absorb nutrients properly, and CD sufferers become malnourished no matter how much they eat.

Celiac disease is also known as celiac sprue, nontropical sprue, and gluten-sensitive enteropathy. Because the body's own immune system causes the damage, it is considered an autoimmune disorder. It is also classified as a disease of malabsorption because nutrients are not absorbed.

Although an association between insulin-dependent diabetes and celiac disease has been recognized for some time and studies have been published of European and Canadian populations, the incidence of CD among American children with diabetes has not been established. The only other US-based study of this type, performed in New York and published in 1993, reported a 1.4% incidence of CD among the patients studied.

CD Symptoms in Children
Celiac disease can show up as a confusing array of symptoms, which may or may not occur in the digestive system. For example, one person might have diarrhea and abdominal pain, while another person experiences irritability or depression. In fact, irritability is one of the most common symptoms of CD in children.

In infants and children, symptoms of celiac disease may include one or more of the following:

• abdominal bloating, pain and gas; pale, bad-smelling stool; chronic diarrhea
• weight loss; “failure to thrive” in infants or delayed growth in older children
• unexplained anemia (low red blood cell count)
• fatigue, irritability or behavior changes

Anemia, weight loss and delayed growth are signs of malnutrition. This is a serious problem for any child, because children need adequate nutrition to develop properly. In children who also have diabetes, maintaining proper nutrition and blood sugar balance can be particularly complicated. It can be difficult for to balance food intake, physical exertion and insulin dosage in ways that keep the blood sugar stable. Diabetics must regulate their blood sugar carefully to prevent the eventual onset of conditions such as heart disease, blindness, kidney failure and amputations of the toes, feet or legs. Diabetes is the seventh leading cause of death in the United States.

Diagnosing Celiac Disease
People with celiac disease have higher than normal levels of certain antibodies in their blood. Antibodies are produced by the immune system in response to substances that the body perceives to be threatening. To diagnose celiac disease, physicians test blood to measure levels of antibodies to gluten. If the tests and symptoms suggest celiac disease, the physician may remove a tiny piece of tissue from the small intestine to check for damage. This is done in a procedure called a biopsy: the physician eases a long, thin tube called an endoscope through the mouth and stomach into the small intestine and takes a tissue sample. This is the surest way to diagnose celiac disease.

Treating CD with Diet
The only treatment for celiac disease is to follow a gluten-free diet. This means avoiding all foods that contain wheat (including spelt, triticale, and kamut), rye, barley, and possibly oats. (Some people with CD can eat oats, but this should be discussed with a physician or dietitian.) In other words, most grain, pasta, cereal and many processed foods are out of the picture for people who need to live gluten-free. According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), a gluten-free diet will stop symptoms, heal existing intestinal damage, and prevent further damage. Improvements begin within days of starting the diet, and the small intestine is usually completely healed in 3 to 6 months. (It may take up to 2 years for older adults.)

Despite these restrictions, people with celiac disease can eat a well-balanced diet with a variety of foods, including bread and pasta. For example, instead of wheat flour, people can use potato, rice, soy, or bean flour. Gluten-free breads, pastas and other products are available in most health-food stores and from special food companies.

Plain meat, fish, rice, fruits, and vegetables do not contain gluten, so people with celiac disease can eat these foods. Of course, those with co-existing diabetes will need to monitor their intake appropriately to stay within their normal limits. Combining a gluten-free diet with the dietary challenges imposed by diabetes can be daunting, but it is still possible to lead a healthy existence with education and careful planning.

Incidence of CD in the United States
Celiac disease is the most common genetic disease in Europe. In Italy about 1 in 250 people and in Ireland about 1 in 300 people have celiac disease. It is rarely diagnosed in African, Chinese, and Japanese people. In Italy, all children are screened by age 6 so that even asymptomatic disease is caught early. In addition, Italians of any age are tested for the disease as soon as they show symptoms. As a result of this vigilance, the time between when symptoms begin and the disease is diagnosed is usually only 2 to 3 weeks. In the United States, the time between the first symptoms and diagnosis averages about 10 years.

Americans are not routinely screened for celiac disease. Only one in 4,700 Americans have actually been diagnosed with CD, but researchers question its apparent rarity since many US citizens descend from European ethnic groups in whom the disease is common. A recent study in which random blood samples from the Red Cross were tested for CD suggests that as many as 1 in every 250 Americans may have it. Celiac disease could be underdiagnosed in the United States because it is difficult to diagnose and celiac symptoms can be attributed to other problems. In addition, many US doctors are not knowledgeable about the disease and only a handful of U.S. laboratories are experienced and skilled in testing for celiac disease.

Because of the severe implications of the disease and its incidence in children with insulin-dependent diabetes, screening should be routine in this population. Since celiac disease is hereditary, family members of people who have been diagnosed may need to be tested for the disease. The longer a person goes undiagnosed and untreated, the greater the chance of developing malnutrition and other complications.

More research is needed to find out the true prevalence of celiac disease among Americans and its co-existence with other disorders such as diabetes. The new study by Medical College of Wisconsin researchers adds valuable insight to this exploration.

Eileen Early, RN, BSN
HealthLink Editor
Office of Clinical Informatics
Medical College of Wisconsin

This article includes information from the Department of Pediatric Gastroenterology; the Department of Pediatric Endocrinology, Diabetes & Metabolism and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) of the National Institutes of Health.