Coeliac disease and gluten intolerance: an overview

John Scott
reviews recent research

Coeliac disease involves an auto-immune reaction to gluten (a protein found in wheat, rye and barley) that results in damage to the gut preventing the absorption of nutrients.

The problem is thought to arise because some individuals have a specific type of tissue which recognises wheat proteins but lack a specific protective DNA sequence in the interleukin-2 and interleukin-21 gene region, so they are likely to have a reduced defence against intestinal inflammation and, thus, be more likely to have coeliac disease.

Until recently, intestinal biopsy was the only way to diagnose coeliac disease, but the introduction of a simple blood test to measure Ig anti-tissue transglutaminase (IgAtTG) – a well known marker for coeliac disease - has made initial diagnosis very much easier. The Biocard Coeliac Test Kit is available from pharmacies and supermarkets as well as online.

The coeliac blood test
All that is required is a small pin-prick of blood from a finger tip. A clear yes or no result appears in 10 minutes. However, the Biocard Coeliac Test is not suitable for children under five and the test will only show the presence of coeliac disease if the patient still has gluten in their diet, so it should be used before making any dietary changes.

Whilst the Biocard Test is as accurate as the blood tests used by GPs, no test is 100% reliable, so its results should only be taken as a guide. Only a biopsy taken from the intestine will confirm the diagnosis definitively.

Patients should therefore consult their GP if they obtain a positive result, or if the test shows a negative result while symptoms continue.

If a firm diagnosis is obtained, the GP should ensure that any associated problems (with osteoporosis and anaemia) are identified and treated. The patient should be referred to a dietitian for help with avoiding gluten in their diet, and be provided with prescriptions for gluten-free foods.

Once a patient with coeliac disease has been on a gluten-free diet for a period, the gluten antibody blood test will again prove useful to check whether or not antibody levels have decreased and whether the diet has been effective in reversing damage to the intestinal lining.

Capsule camera diagnosis
Thanks to the capsule camera - otherwise known as a video capsule
enteroscope or 'PillCam' - biopsies may soon become a thing of the past. According to a recent report in the American Journal of Gastroenterology, this new device can accurately detect intestinal atrophy in patients suspected of having coeliac disease.

The video camera-in-a-capsule is about the size of a large vitamin pill and is easily swallowed. It journeys along the gastrointestinal tract collecting data, which is transmitted initially to a receiver worn on the patient's belt and is eventually downloaded by the doctor to a computer. The capsule is disposable, so does not need to be retrieved when it is passed from the body.

A recent study from the University of Milan compared the results of 43 patients with signs of coeliac disease tested with the PillCam and by a conventional biopsy.

Of 32 patients found to have abnormal tissue, 28 were diagnosed with coeliac disease by the PillCam, and the investigators concluded that the high-quality images it provided were a valid alternative to a biopsy.

Being minimally invasive, the PillCam is more acceptable to patients, and it allows exploration of the entire small intestine, which may lead to the identification of abnormalities beyond the reach of an endoscopy.
(Source: American Journal of Gastroenterology Aug. 2007 102(8): 1624-31)

The hidden epidemic of gluten intolerance
Until recently, gluten intolerance was thought to be rare, with an estimated one in 5,000 people having the disease, but new research suggests that one in 100 may be affected and that four out of five of these suffer unnecessarily, without knowing that coeliac disease is responsible for their symptoms. This amounts to nearly 500,000 people in the UK.

When the IgAtTG blood test was carried out randomly, one in 167 apparently normal, healthy children and one in 111 seemingly normal, healthy adults tested positive for coeliac disease (Journal of Pediatric Gastroenterology and Nutrition, vol 31 , pp 104).

Diversity of symptoms
Traditionally, only digestive symptoms were linked to coeliac disease, but it is now realised that many coeliacs have no digestive symptoms at all, and that a whole range of apparently unconnected conditions may in fact be due to gluten sensitivity.

Conditions which may be associated with gluten include ADHD, anaemia, autism, autoimmune diseases, bone and joint pain, breathlessness, chronic fatigue, brain fog, depression, dermatitis herpetiformis, epilepsy, facial pain, failure to thrive, hair loss, headaches, infertility and pregnancy complications, migraine, mouth ulcers, neurological disorders, osteoporosis, rheumatoid arthritis, skin problems, tiredness, type 1 diabetes, upper respiratory tract disorders, vitamin K deficiency and weight loss. (Click here for more on other symptoms.)

It appears that many people with these and other conditions have fewer symptoms and recover faster when they are on a gluten-free diet.

One example of a condition which has been linked with gluten sensitivity a number of times in the medical literature is trigeminal neuralgia: sufferers had decreased facial pain when they stopped eating gluten. Click here for more.

If gluten intolerance is left undiagnosed and untreated, sufferers also have a high risk of developing osteoporosis and infertility as well as an increased risk of cancer.


Gluten Freedom by Alessio Fasano
Coeliac Disease: What you need to know by Alex Gazzola
Seriously Good Gluten-Free Cooking by Phil Vickery

Click here for more articles on the causes of coeliac disease.



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