What is Celiac Disease?

It is a hereditary condition that involves gluten intolerance, whereby the digestive system, particularly the small intestine, is impaired by not being able to absorb certain nutrients. One percent of the worldwide population has been found to have celiac disease, with its occurrence increasing in recent years. While many people in the US have never been diagnosed, it seems to be more common in Caucasian people.

“Celiac disease is an autoimmune disorder that affects approximately 1% of the population worldwide. As many as 6 of 7 cases of celiac disease remain undiagnosed. This discrepancy falls in line with the widely accepted ‘celiac iceberg’ concept and may be due to the fact that patients have variable presentations of celiac disease. Manifestations of celiac disease range from typical gastrointestinal complaints characterized by malabsorption and diarrhea, to more silent forms in patients without overt gastrointestinal complaints. Non gastrointestinal presentations may include anemia, thyroid dysfunction, osteoporosis, liver function test abnormalities, and skin manifestations such as dermatitis herpetiformis. The variable presentations create a clinical challenge to physicians in reaching an early diagnosis. As a result, delay in diagnosis is not uncommon and does not go without consequence. Undiagnosed celiac disease can lead to osteoporotic fractures, infertility, unnecessary surgical procedures including bowel resection, and malignancy. As the majority of cases of celiac disease can be treated with a strict gluten-free diet alone, adherence to this diet can reverse the risk for adverse clinical outcomes.”¹

 

“Celiac disease is diagnosed typically in early childhood around age of 2 years. A second peak is found around age of 40 years. Most symptoms are due to malabsorption of nutrients and vitamins. However, the clinical manifestations differ greatly, depending on each case and ranging from asymptomatic (silent) to full blown (symptomatic, clinically overt) celiac disease. The severity of symptoms is not necessarily proportional to the severity of the mucosal lesions and patients with total villous atrophy can be asymptomatic or present with subclinical symptoms such as iron deficiency or muscle cramps. Nowadays, more subjects present with asymptomatic or mild celiac disease than with the classical symptoms of severe malabsorption.

The term “atypical” celiac disease is used for patients who present with extraintestinal symptoms like Immunoglobulin A (IgA)-nephropathy, hemosiderosis of the lungs and a variety of neurological diseases. Antibodies and typical small intestinal changes can be found. Early diagnosis is desirable since many of these symptoms can disappear after the initiation of a gluten-free diet.

The term “latent” celiac disease refers to subjects who will develop the disease later in life but who do not have a flat mucosa despite a gluten-containing diet. Increased intraepithelial lymphocytes (IEL) and positive endomysium antibody (EMA) or positive tissue transglutaminase (tTG) antibody tests are sometimes found in these subjects. What triggers the onset of the disease in these subjects remains unknown.”²

 

One curiosity about celiac disease relates to the fact that people can be sensitive or intolerant to gluten without having the disease; this is known as non-celiac gluten sensitivity. Research is still in progress on how to differentiate between celiac disease and other precursor conditions. What is known is that celiac disease has multiple manifestations and has been connected to liver, pancreatic illnesses and even cancer.

“Non-celiac gluten sensitivity, a condition in which individuals do not have the diagnostic features of CD but nonetheless develop celiac-like symptoms upon exposure to dietary gluten, is important to consider in the differential diagnosis of CD. Symptoms alone cannot reliably differentiate CD from non-celiac gluten sensitivity as there is often substantial overlap in symptoms between the two conditions. Objective tests including celiac serology and small-intestinal histology (both obtained while the patient is consuming a gluten-rich diet) and HLA-DQ typing (to rule out CD if negative) are needed to differentiate between the two disorders. Knowledge of the pathogenesis, epidemiology, and natural history of non-celiac gluten sensitivity is quite rudimentary. However, at this time, it appears that non-celiac gluten sensitivity does not have a strong hereditary basis, is not associated with malabsorption or nutritional deficiencies, and is not associated with any increased risk for auto-immune disorders or intestinal malignancy. Given these major differences in natural history and outcomes, the differentiation of CD and non-celiac gluten sensitivity is important for advising patients regarding the importance of ongoing disease monitoring, the required duration and strictness of adherence to the GFD, and for counseling and testing of family members.”³

 

“For symptomatic celiac disease patients, the introduction of a gluten-free diet (GFD) can lead to significant improvement in symptoms, abnormal biochemical measures, and impaired quality of life. Long-term treatment also reduces the risk of malignant and nonmalignant complications. Concerns remain about the long-term consequences in patients with asymptomatic celiac disease and whether maintaining a lifelong GFD is necessary for all patients. Recent studies have suggested that patients who are detected during screening, most of whom can be regarded as asymptomatic, can improve their quality of life in the longer term with a GFD.”⁴

 

What Are Typical Symptoms and How Is It Diagnosed?

“Celiac disease is a frequent disorder (1% prevalence) in populations of mainly Caucasoid descent. The disease develops at all ages, and most patients are diagnosed in adolescence. The disease is caused by an abnormal immune response to gluten proteins of wheat, rye, and barley. Current treatment is life-long elimination of gluten from the diet. There is increased morbidity and mortality associated with celiac disease but less so than previously thought. Treatment with gluten-free diet appears to reduce these risks.  Celiac disease has a diverse clinical picture ranging from tangible symptoms such as malabsorption, diarrhea, weight loss, and osteoporosis to vaguer symptoms such as iron and folic acid deficiency, arthralgia, fatigue, and abdominal discomfort. Celiac disease often presents without diarrhea, and celiac disease patients may even be obese. Asymptomatic patients can be found. Thus, the disease is impossible to diagnose on clinical grounds alone. The diagnostic workup is performed with a number of tests, of which many have immunological basis.”⁵

 

Diarrhea, anemia, intestinal pain, excessive gas, weight loss, fatigue, and osteoporosis are the most common symptoms. However, some of those who suffer from this disease do not present any manifestations. Even when they do, celiac disease can be difficult to diagnose because the clinical picture can coincide with other illnesses.

Celiac disease can develop under conditions of severe stress, injury, gastrointestinal infection, and pregnancy. Gluten intolerant people have an increased risk of mortality if intestinal complications are not controlled. Possible complications, like cancer, can be dead serious. However, the rate of mortality is low when adequate dietary adjustments are made. Also, improvements in diagnosis and treatment are continuously being developed in various parts of the world.

A blood sample analysis needs to be performed because it has been found that people with intolerance to gluten have a disproportionate number of certain antibodies. Biopsies of the small intestine can also be obtained. To do that, doctors use an instrument known as an endoscope.  

 

What Type of Foods Contain Gluten?

Gluten is a protein primarily found in wheat, barley and rye. This protein is incompletely digested by intolerant individuals. Hidden or unknown sources of gluten can be found in oats, soy sauce, and processed meats, just to name a few.

“Hidden sources of gluten are frequently present in what seem to be safe foods. Suspicious ingredients include hydrolyzed vegetable protein, modified food starch (and starch in foreign foods), malt or malt flavoring, vegetable gum (oat), mono- and diacylglycerols, and natural flavorings. Listings of gluten-free foods must be reviewed regularly for changes in the manufacturer’s ingredient list. It may be difficult to ascertain the exact grain source of ingredients as a result of outsourcing of ingredients. Even nonfood items may be sources of trace gluten and can cause symptoms in more sensitive patients. Such sources include medications (both prescription and over-the-counter); glues, pastes, and dry wall filler; airborne flour; communion wafers; fat replacers; cross contamination; and grain-derived alcoholic drinks. Contamination of supposedly gluten-free products can also occur during harvesting, processing, and packaging; in the store (for example, in flour bins); and in the kitchen. Obtaining flour substitutes from reliable sources that cater to patients with celiac disease is encouraged.

Secondary lactose intolerance is common but usually resolves once the damage to the gut has healed. Temporary restriction of lactose ingestion or use of a lactase preparation may suffice for treatment. Many patients with celiac disease report intolerances to other non-gluten-containing foods. The mechanism of these intolerances is not known.

Specific nutritional supplementation may be used to correct deficiency states. The most common are supplementation with iron, folate, calcium, and fat-soluble vitamins. Bone density should be measured in adults at or shortly after the time of diagnosis because osteopenic bone disease is common and may be profound in patients with newly diagnosed celiac disease.”⁶

 

What Issues Should We be Aware Of?

An individual with celiac disease must follow a strict gluten-free diet. A doctor or nutritionist can advise what foods will be required for a proper diet. Bread and pasta substitutes are easily found, but they’re pricier.

“Celiac disease is the only autoimmune disease that goes under control with diet free of gluten. All gluten containing foods should be restricted. Patient should avoid wheat, rye and barley. Usually a dietitian consultation is needed to explain the diet not allowed. Gluten free diet should be considered for the whole life. In the first six months the patient should restrict the milk till the intestinal villi are back to normal. This reduces gas, distention and abdominal pain due to lactose intolerance. They can use potato, rice and soy.”⁶

 

After a diet free of gluten is formally practiced, the intestinal mucosa of the patient should show marked progress. Hidden sources of gluten are especially problematic for celiac patients, since their exposure can give rise to recurring symptoms.

Patients with celiac disease need to be well-informed to better manage all symptoms, reduce the risk of serious health complications, and improve their quality of life.

 

References:

(1) Paez, M. A., Gramelspacher, A. M., Sinacore, J., Winterfield, L., & Venu, M. (2017). Delay in diagnosis of celiac disease in patients without gastrointestinal complaints. The American journal of medicine, 130(11), 1318-1323. Available online at https://www.amjmed.com/article/S0002-9343(17)30606-X/pdf

(2) Holtmeier, W., & Caspary, W. F. (2006). Celiac disease. Orphanet journal of rare diseases, 1(1), 3. Available online at https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1435993/

(3) Rubio-Tapia, A., Hill, I. D., Kelly, C. P., Calderwood, A. H., & Murray, J. A. (2013). ACG clinical guidelines: diagnosis and management of celiac disease. The American journal of gastroenterology, 108(5), 656. Available online at https://www.medilab.at/files/ACG_Guideline_Coeli.pdf

(4) Bai, J. C., Zeballos, E., Fried, M., Corazza, G. R., Schuppan, D., Farthing, M. J. G., … & Krabshuis, J. H. (2005). Celiac disease. WGO-OMGE Practice Guidelines. World Gastroenterology News, 10(2 Suppl), S1-S8. Available online at:

http://www.spg.pt/wp-content/uploads/2015/11/2012-Celiac-Disease_long_FINAL.pdf

(5) Sollid, L. M., & Lundin, K. E. A. (2009). Diagnosis and treatment of celiac disease. Mucosal Immunology, 2(1), 3. Available online at https://www.researchgate.net/publication/23660160_Diagnosis_and_treatment_of_celiac_disease. Available online at https://www.researchgate.net/publication/23660160_Diagnosis_and_treatment_of_celiac_disease

(6) Murray, J. A. (1999). The widening spectrum of celiac disease. The American journal of clinical nutrition, 69(3), 354-365. Available online at https://academic.oup.com/ajcn/article/69/3/354/4694128

(7) Karjoo, M. (2014). Celiac Disease. International Journal of Pediatrics, 2(3.2), 5-7. Available online at http://ijp.mums.ac.ir/article_2955_8b4cc6c89fc3406983e45d866093e91e.pdf