Coeliac disease is a common inflammatory disease of the small bowel triggered by the ingestion of gluten proteins, in people who have a particular genetic makeup. The damage to the small intestine results in nutritional deficiencies and possible long-term medical complications.
It is thought that about 1 in 70 Australians have coeliac disease and that about 80% of this group remain undiagnosed.
Coeliac disease can be diagnosed at any age, so one negative test for coeliac disease may not mean negative for life.
Gastrointestinal problems such as nausea, vomiting, diarrhoea, bloating and weight loss are commonly experienced. However, we now know that people who appear to have no symptoms at all can in fact have coeliac disease. The signs and symptoms which could be overlooked are feelings of general malaise, low blood iron, osteoporosis, infertility in females, constipation, loss of tooth enamel, short stature, apparent food intolerances to name some.
If the disease remains undiagnosed or gluten remains in the diet, cancers of the gastrointestinal tract, osteoporosis, liver and heart disease, neurological effects or refractory (unresponsive) coeliac disease may be some of the long-term medical outcomes experienced.
You need to be correctly diagnosed with coeliac disease before starting a gluten free diet. Once gluten has been removed from your diet coeliac disease cannot be diagnosed without eating at least 2 slices of bread or equivalent wheat product per day, for up to 6 weeks (or more), before any testing is done. Up to 4 slices of bread daily is encouraged if symptoms allow.
Gluten must be present to stimulate the changes that the tests measure, i.e. an increase in coeliac specific antibodies and villous damage in the small intestine.
If sufficient gluten is currently in the diet, screening blood antibodies tests can then be ordered by your local doctor. This blood test does not diagnose coeliac disease. The blood test is used to indicate whether or not it is likely that you have coeliac disease. If the antibody levels come back higher than expected, this means there is an increased chance that you have coeliac disease and a small bowel biopsy, with a Gastroenterologist, is then done to confirm if there is any damage to the villi in your small intestine.
The villi help to absorb nutrients from your food. Only the small bowel biopsy diagnoses whether or not you have coeliac disease.
If the antibodies are in the normal range, then coeliac disease is not suspected at that time. However, one test for coeliac disease does not mean you are negative for life. You can develop the disease at any age so it may be suggested that the blood screening test be repeated every 3-5 years, with gluten in the diet.
There may be circumstances where children are not biopsied, but the blood tests need to be extremely high to diagnose without biopsy. The Medical Advisory Board to Coeliac Australia support the use of biopsies to diagnose coeliac disease.
If you have not been eating gluten and need to test for coeliac disease, a genetic test is available to narrow down the group of people who may need to load gluten back to the diet for the antibody tests. The genetic test can also indicate if you require repeated blood antibody tests.
Roughly 30-40% of people in the world carry certain genetic markers found in most people (99.6%) with coeliac disease, however only approximately 3% of people who have these genetic markers go on to develop coeliac disease. This genetic test therefore does not diagnose coeliac disease but can rule it out. Nor does it indicate a sensitivity to gluten.
Gluten Free Diet
People who have been diagnosed with coeliac disease need to avoid gluten in their diet.
Gluten is present in the grains wheat, rye, triticale, barley and controversially oats. It may also be present in much smaller amounts in ingredients made from these grains such as wheat derived thickeners and starches.
After the diagnosis of coeliac disease is made, you will be asked to follow a strict gluten-free diet for life.
Dr. Kim Faulkner-Hogg is a dietitian who specialises in coeliac disease and can give you in-depth information about both small and large amounts of gluten in our foods, thereby helping you to create your gluten free diet.
After 6-18 months of following a gluten-free diet it is usual to have another small bowel biopsy performed to ensure that the villi in the gut are recovering.
Response time to the gluten free diet
In adults it often takes 9-16 months for the blood antibody levels to fall into the normal range. It can often take 6-18 months (or even 2 years) for the symptoms to settle. The small bowel often takes 6 months to 2-5 years to improve. It seems that the older the person is at diagnosis the longer it may take to recover at each of these indices and recovery may not always be complete.
Children generally have a faster response to the gluten free diet than in adults. In many, symptoms, biopsy and blood results return to normal in a few months to a year, when a gluten free diet is followed. Growth & bone mineral density can be regained in children and adolescents, and in most, any iron deficiency anaemia is reversed. It is believed that an early diagnosis and start on the gluten free diet will result in less future medical problems.
Long term nutrition when eating gluten free
At the start of your gluten free diet, vitamin and mineral supplements may be recommended or you may experience a transient intolerance to dairy foods. As the small intestine recovers, these issues should improve or resolve.
It is essential that you have a well- balanced gluten free diet and that you are aware of particular nutrients that may be compromised with your life-long gluten exclusion.
It is recommended that all people diagnosed with coeliac disease join Coeliac Australia or the local Coeliac Organization in the country in which you live.
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