Celiac Disease Nursing CE Course

op celiac disease. The actual response is triggered by a gluten protein segment known as gliadin. When people susceptible to celiac disease ingest gliadin, their T-cells respond abnormally, resulting in inflammation affecting the small intestine. As a result, they commonly have increased levels of three antibodies: transglutaminase, endomysium, and gliadin (Hinkle & Cheever, 2018; Norris, 2020). 

In addition to genetic susceptibility, other risk factors are involved in developing celiac disease. As is seen in other autoimmune disorders such as type I diabetes mellitus, having one autoimmune disorder increases the risk of developing other autoimmune diseases. While research does indicate various contributing factors, such as genetics, in the development of celiac disease, the exact etiology is unknown (Rubin & Crowe, 2020). Other risk factors include: 

• what and how infants are fed (i.e., breastfeeding and delayed introduction to gluten may prevent gluten sensitization)  

• history of GI infections and bacteria within the intestinal tract 

• emotional or physical stress that may initiate an immune response following significant events such as childbirth, surgical procedures, and infections  

• race: White people have a higher prevalence than non-White people 

• sex: females have a higher prevalence than males 

• Down syndrome 

• Addison’s disease 

• autoimmune thyroid disease 

• microscopic colitis (Rubin & Crowe, 2020) 

Clinical Manifestations 

Symptoms of celiac disease can vary widely from person to person. With symptoms coming and going, differentiating symptoms of celiac disease from other digestive disorders can be challenging. For children with celiac disease, altered absorption of nutrients can significantly impact normal growth and development. In an infant or young toddler, symptoms may include failure to thrive, diarrhea, muscle wasting, abdominal distention, or malnutrition. An adolescent's symptoms may include anemia, short stature, nausea and vomiting, bloating, pale and foul-smelling stools, dental defects, mood changes or irritability, weight loss, delayed puberty, and constipation. Children may also experience neurological symptoms, including attention-deficit hyperactivity disorder (ADHD), learning disabilities, headaches, seizures, and lack of muscle coordination (Lebwohl & Rubio-Tapia, 2021; NIDDK, 2020d). 

Symptoms of celiac disease in adolescents or adults can vary from person to person and manifest differently based on the person's age. The symptoms of celiac disease are typically due to inflammation involving the GI tract. They are categorized as either an early symptom or a result of prolonged inflammation and consequent malabsorption. Some digestive symptoms may include but are not limited to diarrhea (i.e., loose, greasy, bulky, and foul-smelling stool), weight loss, abdominal bloating, flatus, abdominal pain, constipation, oral ulcerations, and nausea/vomiting (Lebwohl & Rubio-Tapia, 2021; NIDDK, 2020d). 

Many adults impacted by celiac disease do not present to a healthcare provider (HCP) with GI symptoms, but fatigue or iron deficiency anemia related to poor absorption. Atypical symptoms are not usually GI-related but are related to long-term inflammation or nutritional deficits caused by celiac disease impacting other body systems. Another atypical sign is osteopenia or osteoporosis, which is a decreased bone density. From a central nervous system standpoint, the patient may report migraine headaches or paresthesia of the feet and hands. In more significant cases, the patient may experience poor balance, decreased cognition, depression, and seizures. The reproductive system may be impacted, causing early menopause and infertility. Dermatitis herpetiformis is a condition that results in pruritis and a blistery skin rash caused by gluten intolerance (see Figure 2). The rash usually occurs on the knees, torso, scalp, elbows, and buttocks. Dermatitis herpetiformis is often associated with changes to the small intestine lining. Dental examinations may reveal abnormalities indicative of celiac disease, including dental enamel hypoplasia, aphthous ulcers, and delayed eruption of teeth (Lebwohl & Rubio-Tapia, 2021; NIDDK, 2020d). 

The small intestine is the portion of the GI tract most impacted by celiac disease. There are a variety of repercussions of an impaired ability to absorb essential nutrients, vitamins, and minerals. Most nutrients and vitamins are absorbed throughout the three segments of the small intestine to avoid absorption disorders. The duodenum and jejunum are responsible for absorbing most iron, and the duodenum is accountable for absorbing calcium. It is also important to note that some patients will have vague or no symptoms. A lack of symptoms makes diagnosis complex and lengthy; it may take multiple years to diagnose someone with celiac disease. Eventually, the inflammation worsens, and the consequent damage causes previously absent or vague symptoms to become more significant (Hinkle & Cheever, 2018; NIDDK, 2020d). 

According to the World Gastroenterology Organization, celiac disease can be categorized as classical or non-classical based on the clinical manifestations (Hinkle & Cheever, 2018; NIDDK, 2020d).  

• Classical celiac disease is characterized by signs and symptoms of malabsorption, including weight loss, diarrhea, and steatorrhea (pale, foul-smelling, fatty stools). 

• Non-classical celiac disease is characterized by mild GI symptoms without signs of malabsorption, including abdominal pain, bloating, or excessive gas. These individuals may also experience seemingly unrelated symptoms, including chronic fatigue, iron-deficiency anemia, chronic migraines, reduced bone density or fractures, vitamin deficiency (e.g., folic acid and B12), peripheral neuropathy, unexplained chronic hypertransaminasemia (i.e., elevated liver enzymes), difficulty losing weight, dental enamel defects, depression and anxiety, dermatitis herpetiformis, late menarche or early menopause, and unexplained infertility.  

• Silent celiac disease is a type of non-classical disease that is asymptomatic. These individuals do not experience symptoms but have villous atrophy damage within their small intestines.   

Diagnostic Criteria 

The American College of Gastroenterology (ACG) 2013 guidelines for diagnosing and managing celiac disease are the most updated version published. According to the ACG guidelines, when a patient presents with clinical symptoms suggestive of celiac disease, the HCP should order diagnostic studies after completing a history and physical exam. The confirmation of celiac disease should be based on a combination of findings, including the medical history, physical examination, serology, and endoscopy and/or biopsy results. The HCP compiles data from the medical record, including signs and symptoms and the physical assessment. Testing should occur before the inception of a gluten-free diet. If the patient starts on a gluten-free diet before completing these tests, the results may appear normal because of the dietary modifications. In addition to testing those with symptoms, there are recommendations for others who should be tested, including persons who have digestive symptoms and a first-degree relative who has been diagnosed with celiac disease, and those who have been diagnosed previously with an associated autoimmune disorder such as type I diabetes mellitus, Down syndrome, or autoimmune liver disease. According to the ACG guidelines, asymptomatic testing for patients with a known first-degree relative with a confirmed celiac diagnosis is controversial but can be considered. The HCP should also test for celiac disease in patients with elevated serum aminotransferase levels when no other etiology is found. Knowing when to pursue celiac disease testing can be challenging because it can mimic other diseases such as irritable bowel syndrome (IBS), lactose intolerance, Crohn’s disease, or intestinal infections (Lebwohl & Rubio-Tapia, 2021; Rubio-Tapia et al., 2013).  

It is sometimes challenging to diagnose celiac disease in children younger than 3 because it takes approximately one year of ingesting products such as cereal containing wheat or barley to produce an immune response to the gluten. If young children are symptomatic, they should be seen and evaluated by a pediatric gastroenterologist. Genetic testing might also be helpful in pediatric patients. Screening for children at risk for celiac disease can occur at age 2 or 3 unless symptoms appear beforehand. Genetic testing alone cannot diagnose celiac disease but can determine if either of the genes associated with celiac disease are present. In addition, antibody testing may not be accurate in children younger than 3 (Lebwohl & Rubio-Tapia, 2021; Rubio-Tapia et al., 2013). 

Antibody Testing 

Diagnostic workup for celiac disease usually starts with serological testing. The immunoglobulin A (IgA) anti-tissue transglutaminase antibody (TTG) test is the gold standard for diagnosing adults and children over 2. For children under 2, deamidated gliadin peptide (DGP) IgA and IgG antibodies should also be included. These tests will assess for antibody proteins, with elevated levels suggesting an immune reaction to gluten. The patient must be currently ingesting gluten to ensure the adequacy of the serum testing. If the patient is not consuming gluten, these tests are inaccurate. The TTG-IgA is the most sensitive diagnostic study and will be positive in approximately 95% (sensitivity) of patients with celiac disease who are ingesting gluten. This test has a specificity of 96%, with an accurately negative result in 96 out of 100 healthy individuals. There is a rare possibility (4%) that a patient with celiac disease would have a negative test. There is also a risk of a false positive in patients with other autoimmune disorders with this test. If there is a high probability of celiac disease and the TTG-IgA results are negative, the ACG guidelines recommend that the HCP order a total serum IgA. This study assesses IgA deficiency, a condition associated with celiac disease that can contribute to a false negative antibody titer result. If the HCP’s assessment indicates a strong probability of celiac disease, additional testing should be performed, including but not limited to endoscopy with a tissue biopsy (Kelly, 2022; NIDDK, 2020c; Rubio-Tapia et al., 2013). 

Additional serological antibody studies can include the IgA endomysial antibody (IgA-EMA); it has a specificity of 100%, making it the most specific test for diagnosing celiac disease. However, this test has some negative aspects: it is less sensitive, so there is a higher incidence of false negatives (5% to 10%), and it is costly to conduct. Therefore, this diagnostic tool is typically reserved for persons who are difficult to diagnose with other available tools. For IgA-deficient patients (2% to 3% of patients with celiac disease), the HCP can order a DGP IgA and IgG. The DGP IgA and IgG test can also be used for patients who test negative for EMA or TTG antibodies. However, the DGP IgA and IgG are not recommended for the primary detection of celiac disease. Most patients with celiac disease can be diagnosed based on these antibody tests. However, if a patient tests negative and symptoms persist, additional testing should include an intestinal biopsy (NIDDK, 2020c; Rubio-Tapia et al., 2013). 

Genetic Testing 

While genetic testing does not confirm the presence of celiac disease, it can be beneficial to screen for the presence of HLA DQ2 and DQ8. When either haplotype is present, it indicates an increased risk of celiac disease (i.e., 3% compared to the general population, which is 1%). HLA typing is present in 98.6% of patients with celiac disease, while only 40% of the general population not diagnosed with celiac disease. In addition, if the person has a first-degree relative with celiac disease and shares the same genotype, the risk of celiac disease increases to about 40%. The genotype validation gives the HCP additional data to formulate a diagnosis. This testing is also helpful to persons with a first-degree relative with celiac disease whose test results do not indicate the same genotype, as this would suggest no additional risk of developing celiac disease (Kelly, 2022; NIDDK, 2020c; Rubio-Tapia et al., 2013). 

There are many factors to consider when deciding to proceed with genetic testing. Genetic testing can be costly, and insurance companies should be consulted to determine reimbursement and out-of-pocket costs. Most specialists would suggest genetic testing for patients who are already on a gluten-free diet but have not been officially diagnosed. Additionally, it may be appropriate for those with a first-degree relative with celiac disease or who have difficulty determining a diagnosis based on various issues. Genetic testing also aids in risk assessment and may assist the HCP and patient in future decision-making. Finally, genetic testing can help clarify previous incongruent results (Kelly, 2022; NIDDK, 2020c; Rubio-Tapia et al., 2013). 

Endoscopy 

Additional diagnostic tests for celiac disease include an endoscopy or capsule endoscopy exam with intestinal biopsy. A traditional endoscopy allows the HCP to visualize the internal aspects of the GI tract through an endoscope (i.e., a flexible tube with a light and camera attached) to take pictures and gather biopsies, see Figure 3. Similarly, a capsule endoscopy utilizes a swallowed capsule to take photographs and transmit them to view the internal aspects of the GI tract noninvasively. A signed surgical consent form is required for the endoscopy as this is an invasive procedure. The nurse should explain what to expect and give the patient instructions before the procedure. Depending on the facility policy, the patient undergoing an endoscopy must be NPO (nothing by mouth) for 6-8 hours before the exam. The nurse should review which medications to take before the procedure with the patient. There may be some medications the HCP will want the patient to withhold for a few days before the procedure, such as anticoagulants. The patient should be instructed about the procedure and the medications used during the procedure. The nurse will assist the HCP, monitor the patient, and assess the vital signs before, during, and after the procedure. Afterward, the nurse should evaluate the return of the patient’s gag reflex before allowing them to have fluids and food by mouth. The patient should feel safe and secure throughout the procedure, and the nurse or HCP should answer any questions they have (Ignatavicius et al., 2018; NIDDK, 2020c; Rubio-Tapia et al., 2013). 

During a biopsy, the HCP surgically removes small pieces of tissue that pathologists examine for antibodies and the presence of other criteria that would indicate celiac disease. Biopsies allow the pathologist to directly examine the villi in the small intestine for the confirmative signs of celiac disease, including damage and flattening of the villi, presence of inflammation, and antibodies in the tissue and villi. The upper endoscopy with intestinal biopsy is critical to diagnosing patients with suspected celiac disease. The ACG guidelines recommend multiple biopsies of the duodenum (i.e., one or two from the bulb and at least four from the distal duodenum) for confirmation of celiac disease. The evaluation may include a skin biopsy if the patient has dermatitis herpetiformis (NIDDK, 2020c; Rubio-Tapia et al., 2013). 

Treatment Options 

Treatment involves avoiding gluten to reduce the immune response and ultimately decrease the inflammation in the small intestine. While no cure is available, most people who follow a gluten-free diet will experience diminished symptoms and reduced risk of complications. The patient must recognize the need for lifelong compliance to prevent chronic inflammation, long-term damage, and potential complications. Children will usually have decreased inflammation and healing of the intestinal tract quicker than adults. If the patient is experiencing complications related to nutritional deficits, supplements containing copper, folate, iron, zinc, or vitamins B-12, D, or K may be indicated. Most patients should take the supplements orally, but if malabsorption is significant, the supplements may be administered via injection (Ciclitira, 2021; NIDDK, 2020e; Rubio-Tapia et al., 2013).  

Wheat, barley, bulgur, durum, farina (milled wheat), malt, rye, semolina, spelt, and triticale contain gluten. The nurse should facilitate a referral to a dietitian who can help the patient understand all the aspects of this diet. The patient will need to learn to read labels and identify all potential sources of gluten. Some patients might be able to eat small amounts of gluten and not experience symptoms, but underlying long-term inflammation remains a concern. Gluten is also found in prescription and over-the-counter (OTC) medications, including vitamins, minerals, and herbal supplements. Other products that may contain gluten include makeup (lip products), oral health preparations (e.g., toothpaste and mouthwash), products with adhesives (envelopes and postage stamps), and modeling clay (Play-Doh; Ciclitira, 2021; NIDDK, 2020e; Rubio-Tapia et al., 2013). 

The dietitian, HCP, and nurse can help the patient learn to read labels to assist them with their quest to be gluten-free. The dietitian initially spends time with the patient teaching them about labels. The nurse should reinforce the content and answer any questions during follow-up visits. Understanding celiac disease and its dietary implications can be complicated, and the more support the patient has, the more successful they are likely to be. If a label on a package says gluten-free, then this product has met the requirements by the FDA to be labeled as such. The FDA allows this labeling on products with less than 20 parts per million of gluten. It is still a good idea for patients to review the ingredients list before ingesting the product. The healthcare team should help patients identify ingredients and words that indicate hidden gluten, such as brewer’s yeast and oats. Oats could be contaminated by wheat products during factory processing; thus, people with celiac disease should only eat gluten-free oats (NIDDK, 2020e; Rubio-Tapia et al., 2013).  

Besides the obvious products, most beers contain gluten, although there are several available in the US now that are safe. It is sometimes difficult for parents and children to determine which candy is safe, as many sweets contain gluten. Other products that usually contain gluten include gravy, imitation meats or seafood, most processed lunch meat, prepared rice mixes, soy sauce, and most salad dressings or sauces. In addition, some snack foods (e.g., chips) can have gluten, and many soups (e.g., cream-based soups). The nurse can help patients find reliable online resources that will help them determine which candies and other snacks are safe. There is valuable information on gluten-free diets on the Celiac Disease Foundation website. In addition, many cookbooks and online sites contain gluten-free recipes, which are helpful, especially for baking and holiday cooking. These cookbooks will have guides about various flours to substitute in specific baked goods to achieve a palatable taste and texture (Celiac Disease Foundation, n.d.-a; Raiteri et al., 2022).  

Convenient gluten-free foods include eggs and fresh meats, but anything prepared with breading, batter, or marinades may contain gluten. Fresh fruits and vegetables, lentils, most dairy products, nuts, potatoes, distilled liquors, and wine are all gluten-free. In addition, patients can try grains like amaranth, buckwheat, corn (cornmeal, corn tortillas), quinoa, rice, and gluten-free flours (often rice, sorghum, almond, or potato-based). The patient should carefully read all labels to ensure the ingredients are safe (Celiac Disease Foundation, n.d.-a; Raiteri et al., 2022). 

Dermatitis herpetiformis is typically treated with a gluten-free diet and medications, such as dapsone (Aczone). Dapsone (Aczone) is an oral anti-infective medication with anti-inflammatory properties. Before starting dapsone (Aczone), the HCP must ensure the patient has no conflicting allergies or other health conditions (e.g., hypersensitivity to dapsone [Aczone], allergy to sulfonamide antimicrobials, pre-existing peripheral neuropathy, significant cardiopulmonary disease, liver, or renal disease) that would contraindicate its use. While it is not contraindicated, there are no specific studies regarding the use of this medication in pediatrics or geriatrics. The initial dose of dapsone (Aczone) should be low (50 mg) and titrated (300 mg) as the patient tolerates. The dosing of dapsone (Aczone) should be titrated up or down to the minimal effective dose. It should be taken at the same time each day. The rash should improve in a few days but may take longer to resolve completely. The patient should notify the HCP if the rash worsens. Common side effects include back, leg, or stomach pain, nausea and vomiting, headache, dizziness, fever, anorexia, and insomnia. Some rare adverse effects are pruritus, redness, scaling or peeling of the skin, increasing skin rash, unusual fatigue, mood or other mental changes, paresthesia, sore throat, abnormal bleeding, and jaundice. Patients taking dapsone (Aczone) must have a complete blood count (CBC) before initiation and routinely (i.e., every week for four weeks, then every two weeks to week twelve, then every three to four months) while taking the mediation based on the risk of agranulocytosis, aplastic anemia, or other blood dyscrasias. For persistent intestinal inflammation in patients with unresponsive or refractory celiac disease, the HCP may need to prescribe steroids or other immunosuppressive medications to help control the inflammation and promote healing of the intestinal tract (NIDDK, 2020e; Kurien et al., 2022; Raiteri et al., 2022). 

In summary, the treatment of celiac disease involves adhering to a gluten-free diet indefinitely to reduce inflammation and current symptoms, allow for healing of the GI tract, and prevent long-term complications. The patient should be encouraged to follow up with a dietitian for any concerns about their diet or education on reading labels. The HCP should assess for symptom control, accurate dietary knowledge, and any questions or comments about the disease and how the patient copes. Emotional support is indicated, as a diagnosis of celiac disease requires significant lifestyle changes. Patients with celiac disease should see their provider as indicated in their treatment plan. The healthcare team can also provide information about virtual or local support groups in the community to connect with other people with celiac disease (NIDDK, 2020e; Rubio-Tapia et al., 2013). 

Complications 

Some patients do not have symptoms or have very isolated symptoms, while most patients experience periods of remission and exacerbation. Exacerbations are typically related to dietary noncompliance. Celiac disease symptoms that do not resolve or respond to a gluten-free diet are often called nonresponsive celiac disease. Patients who experience this may be consuming contaminated foods. Contaminated products may be produced in the same area as products containing gluten, such as oats, and the patient is unaware of the manufacturing practices. Other times, the patient is unaware that a particular food preservative or additive contains gluten. To correct or avoid these situations, the nurse should ensure sufficient education regarding reading food labels. Other possible causes of unresponsive celiac disease could be an overabundance of bacteria growing in the intestine, pancreas dysfunction, poor digestion of sugar, or refractory celiac disease. An alternative explanation is an incorrect diagnosis, meaning the patient has something other than celiac disease, such as irritable bowel syndrome (NIDDK, 2020e; Rubio-Tapia et al., 2013). 

Refractory celiac disease is rare but is defined as persistent symptoms of the disorder and inflammation of the small intestine despite adherence to a rigorous gluten-free diet for 6-12 months. Refractory celiac disease is more common in women than men, specifically older women, and can result in significant complications and severe symptoms. Patients with refractory celiac disease often present with severe diarrhea, pain, and considerable weight loss, which could lead to vitamin and mineral deficiencies. Therefore, refractory celiac disease requires more testing and additional treatment beyond a gluten-free diet, such as specialized nutrition and treatment of significant deficiencies. These steps may improve some, while others with unremitting symptoms may develop other disorders (NIDDK, 2020e; Rubio-Tapia et al., 2013). 

Early complications of celiac disease may already be evident at the time of the initial diagnosis. Vigilant compliance to the diet and regular medical follow-up can decrease the risk of long-term complications. One potential complication is worsening malnutrition due to reduced caloric intake or deficiencies in vitamins and minerals, leading to various anemias and other nutritional deficits. One common mineral deficiency is calcium, which could lead to osteopenia, osteoporosis, osteomalacia, and an associated increased fracture risk. Long-term inflammation is associated with infertility and miscarriage related to deficient levels of calcium and vitamin D. Nervous system disorders linked to celiac disease include seizure disorders and peripheral neuropathy. Evidence suggests that celiac disease may also double the risk of coronary artery disease. The inflammatory process in celiac disease may impact the ability to digest lactose or sugar, further complicating the patient’s diet and increasing symptoms. Concerns also exist regarding the development of intestinal cancers such as intestinal lymphoma and others within the small intestine. Celiac disease also increases the risk of developing another autoimmune condition. This risk is dependent upon the patient’s age at diagnosis. The lowest risk is in toddler and preschool patients (about 10%), and the highest is in adults older than 20 (around 35%; NIDDK, 2020e; Rubio-Tapia et al., 2013). 

Research 

The NIDDK, a branch of the NIH, and many other organizations continue to do clinical trials regarding celiac disease. Many clinical trials focus on preventing celiac disease, while other studies look for ways to improve diagnostic tools. There have been significant improvements in the diagnostic tools, but there remains a need to detect celiac disease quicker and more efficiently. Research studies and clinical trials also investigate new treatment options for celiac disease. One such study is exploring antibody therapy for persons not responding to traditional dietary treatment. In addition, there is currently a clinical trial in the recruitment phase by ImmunogenX to review the efficacy and safety of their new medication, latiglutenase (IMGX003). Latiglutenase is a dual enzyme medication that breaks down gluten in the stomach. Research has shown that when taken with meals, latiglutenase offers patients with celiac disease an adjunct to a gluten-free diet. This medication is intended to reduce symptoms and prevent damage to the intestinal tract. Many studies are looking for better options to treat celiac disease, make life easier for those suffering from chronic illness, and prevent long-term complications (Celiac Disease Foundation, 2021; NIDDK, 2020a). 

Conclusion 

Celiac disease has been diagnosed for many years, and research has provided better diagnostic tools for earlier diagnosis. The standard treatment for classic celiac disease is a gluten-free diet and regular medical care, which is successful for most people. However, despite advances, persons with celiac disease must live with a chronic illness and the challenges of finding prepared foods that do not contain gluten. Many new products on the market are gluten-free, but these are often more expensive and lack taste. Research continues for the betterment of those diagnosed with celiac disease by offering providers more robust diagnostic tools, improving the quality of life for patients, and preventing long-term complications (NIDDK, 2020a; Rubio-Tapia et al., 2013).  

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