By Dascha Weir, MD, Associate Director, The Celiac Disease Program, Boston Children’s Hospital
Interest in gluten is on the rise. The recent attention on gluten is primarily centered on avoiding it. The gluten free market has become a billion dollar business as more and more adults, and children, trial this restrictive diet. Many go gluten free as a lifestyle choice. However, many turn to a gluten free diet for medical reasons and for relief of specific symptoms. It is estimated that roughly 10% of the population have gluten-related disorders.
If you or your child feels better on a gluten free diet, involve your medical care provider to figure out why. Knowing where you or your child falls on the spectrum of gluten-related disorders is important.
Gluten and Gluten Free
Technically, gluten is the main structural component of wheat that plays a role in the rising process and elasticity of baked goods. However, the term is commonly used to describe the complex of water insoluble proteins from rye and barley, in addition to wheat. Gluten is found in many food products, beyond baked goods, both as a main component, a hidden ingredient or as a cross-contaminant. It can also be found in other commonly encountered but often unexpected products, including medications.
“Gluten free” is defined by the FDA as being below 20 parts per million. In patients with celiac disease, as little as 50 mg of gluten per day causes activation of celiac disease. While clearly some children benefit greatly from the gluten free diet, the diet is not completely benign and should be reserved for those patients that truly need it. There are clear downsides to this challenging restrictive diet. It can complicate social activities and have a negative impact on quality of life. The diet is frequently low in fiber, iron and B vitamins and can lead to overweight status in both adults and children. Gluten free food is also expensive.
Celiac disease is a chronic immune-mediated enteropathy of the small intestine triggered by exposure to dietary gluten (wheat, rye and barley) in genetically susceptible individuals. Celiac disease occurs in approximately 1:130 people and occurs slightly more frequently in females. People with autoimmune conditions (such as diabetes and thyroiditis), with family members with celiac disease and with specific genetic conditions, such as Down Syndrome are at higher risk of developing celiac disease. In children, the average age of diagnosis is approximately 10 years of age, though it can develop within the first 2 years of life and in adolescence or adulthood.
Children with celiac disease can have a very varied range of symptoms. Gastrointestinal symptoms can range from very mild to quite severe with abdominal pain, diarrhea, constipation and/or abdominal distention/gassiness. Poor growth and suboptimal weight gain can be a presenting sign but many patients with celiac disease have no detectable growth deceleration. Some patients have no gastrointestinal symptoms and are either asymptomatic. Non- gastrointestinal symptoms, such as fatigue, irritability, low muscle tone, headaches, joint pains, delayed puberty, oral sores, dental enamel defects, low bone mineral density or anemia are also seen with celiac disease.
The first step of the medical evaluation for celiac disease is bloodwork. Specific markers in the blood, specifically tissue transglutaminase IgA and endomysial IgA, are usually elevated in cases of celiac disease. These tests are very good at detecting celiac disease but it is important to recognize that not all children with positive celiac blood tests have celiac disease and that celiac disease can occur without positive celiac markers in the blood. For example, these tests can be unreliable if the individual has been on a gluten free diet.
The diagnosis of celiac disease is usually made from small bowel biopsies obtained by upper endoscopy. The autoimmune response in celiac disease involves damage to and inflammation in the small intestine, specifically villous blunting, crypt hyperplasia and increased intraepithelial lymphocytes are seen.
Celiac disease is highly responsive to treatment with a strict 100% gluten free diet with careful avoidance of cross contamination during food packaging and preparation. On a strict gluten free diet, intestinal damage heals and elevated blood tests normalize. Starting a gluten free diet before this evaluation occurs can make it hard to confirm a diagnosis of celiac disease. Patients with CD, particularly those with untreated or suboptimally treated disease, are at higher risk of other autoimmune disorders, osteopenia, infertility, some malignancies and nutritional deficiencies.
Identification of celiac disease allows for appropriate long term monitoring for known associated comorbidities and potential complications. A diagnosis also allows for specialized education to ensure that children and their families understand potential sources of gluten and for extra support to assist in the ongoing vigilance needed to avoid gluten exposure.
Non-Celiac Gluten Sensitivity (NCGS) is a newly characterized disorder that is still poorly understood. Patients with NCGS experience gastrointestinal and/or extraintestinal symptoms that are triggered by gluten and relieved by the removal or reduction of gluten. An important feature of this diagnosis is that it only occurs in the absence of wheat allergy, the absence of positive celiac blood work and the absence of damage and inflammation in the small intestine. Little is known about how common this condition is. The symptoms of NCGS and celiac disease overlap. Gastrointestinal symptoms typically include abdominal pain, bloating, constipation and/or diarrhea. Extraintestinal symptoms include fatigue, headaches, parasthesias, rash and/or joint pain. No blood markers currently exist to help make the diagnosis and the possibility of long term associated risks is unknown.
Other Gluten-related conditions
It is important to recognize that children can feel better on a gluten free diet if they have a wheat allergy or an allergic condition causing inflammation in the esophagus, called eosinophillic esophagitis. Patients with irritable bowel syndrome can also respond to a gluten-free diet, because of the reduction in fermentable oligo-, di- and monosaccarides and polyols (FODMAP).
Importance of a Diagnosis
If your child seems sensitive to gluten, it is important that they are evaluated before initiating the gluten free diet to identify the underlying condition if possible. Partnering with your pediatrician and a pediatric gastroenterologist is highly recommended.