1. Explain to the patient that coeliac disease is a life-long condition
Although many food intolerances can be temporary problems, coeliac disease is caused by an abnormal immune-related response to gluten, found in wheat, barley and rye, in foods. Once triggered, the disease process can only be treated by eliminating gluten from the diet for life.
2. Remember that symptoms may not always be gut related
Do not overlook non-GI symptoms. Tiredness, anaemia, headaches, mouth ulcers, weight loss, skin problems, depression, neurological symptoms, recurrent miscarriages and joint or bone pain can be present with or without gastrointestinal symptoms.
3. Serological testing for screening for coeliac disease
The first stage is to measure coeliac disease specific serology, IgA based tTGA (tissue transglutaminase antibodies) and/ or IgA EMA (endomysial antibodies). At least 2% of people with coeliac disease are IgA negative. If antibody tests results are very low, serum IgA should be measured to screen for IgA deficiency. If IgA deficiency is confirmed, IgG based tTGA may be a useful indicator. If there is any clinical suspicion, referral to a gastroenterologist for further investigations despite negative antibodies.
4. Advise patients to re-introduce gluten before testing
If a patient has already removed gluten or has reduced the gluten content of their diet before either the antibody blood tests or the biopsy, they need to re-introduce it on a daily basis for approximately 6 weeks before the tests are carried out. It is recommended that individuals do not start a gluten-free diet before testing for coeliac disease as the tests identify disease markers which are not produced once the gluten-free diet is established.
5. Exclude coeliac disease before diagnosing IBS
Symptoms for coeliac disease may be similar to irritable bowel syndrome (IBS) and consequently misdiagnosis with IBS is common. The NICE guideline for recognition of coeliac disease1 recommends screening for coeliac disease before a diagnosis of IBS while the NICE guideline for IBS2 states that before a diagnosis of IBS is given, coeliac disease should be excluded.
6. A gluten-free diet is the complete treatment for coeliac disease
This means eliminating the grains wheat, barley and rye, and ingredients derived from these grains from the diet. Although most people with coeliac disease are able to eat uncontaminated oat products (labelled gluten-free), some may also be sensitive to these oat products, and so they will need to avoid these too.
7. Genetic testing can only be used to eliminate the possibility of coeliac disease
Coeliac disease is genetically based, and linked to the HLA antigens, DQ2 and DQ8 with 90% of people with coeliac disease having these genetic types. However, 30% of the population carry these genes so genetic testing can only be used to eliminate the possibility of coeliac disease.
8. Check for dermatitis herpetiformis
Dermatitis herpetiformis (DH) is a skin manifestation of coeliac disease which affects 1 in 10,000 people. DH commonly occurs on the elbows, knees and buttocks, although it may occur anywhere on the body. A skin biopsy is used to diagnose DH. Intestinal biopsy nearly always shows flattening of the intestinal villi, in people with DH, although people with DH may not have the gastrointestinal symptoms which are characteristic of coeliac disease.
9. Screen for other autoimmune conditions
Thyroid disease, type 1 diabetes and autoimmune liver disease occur in association with coeliac disease. Screening for coeliac disease is recommended in people with these associated autoimmune conditions.
10. Be aware of the complications of undiagnosed coeliac disease
Small bowel cancer and osteoporosis are complications of undiagnosed coeliac disease. The risk of malignancy is reduced to that of the general population once established on a gluten-free diet. However, the increased risk of osteoporosis in the coeliac population remains due to less effective absorption. It is recommended that people with coeliac disease have 1000 -1500mg of calcium per day, twice that recommended for the general population. People with coeliac disease should be followed up on an annual basis for assessment of ongoing symptoms, nutritional deficiencies such as iron deficiency anaemia and also to monitor for the development of associated autoimmune diseases, including autoimmune thyroid disease and autoimmune liver disease. Assessment of tTG or EMA antibodies may be used to monitor for compliance to the gluten-free diet.
Dr Jamie Dalrymple is a GP in Norwich and Honorary Senior Lecturer at the Norwich Medical School, University of East Anglia, chair of the Primary Care Society Gastroenterology (PCSG) and member of Coeliac UK’s Health Advisory Committee.
Coeliac UK’s ‘Gut Feeling Week’ takes place from 13-19 May 2013
1. NICE guidelines on the recognition and assessment of coeliac disease. NICE. London 2009
2. NICE guidelines on irritable bowel syndrome: full guidance. CG61. NICE. London. 2008