Forgot password?

Join NutriDesk

Coeliac Disease

US Celiac Disease

Overview

Coeliac Disease [pronounced seel-ee-ak]

This is a permanent small bowel intolerance to gluten found in many grains and common foods.

It affects about 1 in 100 Australians and is an underdiagnosed condition. It is thought that of those suffering from coeliac disease, only 1 in 5 to 1 in 8 have actually been diagnosed with the condition putting them at high risk for the illnesses discussed below.

Often individuals are in their 40's before a diagnosis is made. These individuals have endured a difficult life, one of constant tiredness, a clouded mind and a daily struggle to simply cope with the everyday physical and emotional challenges that life seems to hand out until one bright doctor makes the diagnosis and literally changes the life of this individual dramatically for the better.

Silent coeliac disease has a high prevalence in populations. These individuals are essentially asymptomatic but may be prone to the many clinical complications of the disease: "The high prevalence of silent celiac disease amongst the general population is becoming increasingly well recognized, and the use of increasingly accurate serological testing in primary care will help identify these patients earlier. The pathogenesis of this fascinating disorder is becoming clearer, with genetic, dietary, innate and adaptive immunological factors all contributing, but effective treatments other than dietary restrictions are still some way off." [Advances in Celiac Disease, http://www.medscape.com/viewarticle/551791]

Misdiagnosis as Irritable Bowel Syndrome [IBS]

Coeliac disease is often misdiagnosed as irritable bowel syndrome [IBS]. Anyone with a diagnosis of IBS with symptoms of bloating, abdominal discomfort after food, feeling unwell and tired should discuss genetic screening for coeliac disease with their general practitioner.

The predisposition is from birth but some manifest the disease abruptly while others will slowly develop with symptomatic manifestations occurring in adult life.

The lining of the small bowel is damaged by the reaction to the protein called gluten which is toxic to individuals sensitive to this protein. Over time an individual can suffer from malnutrition and ill health with complications such as osteoporosis, infertility, depression, dental enamel defects, skin rashes such as dermatitis herpetiformis, a constant clouded mind, chronic tiredness, anaemia, irritability, poor weight gain, miscarriages and certain forms of cancer such as lymphoma of the small bowel.

Often a gastroenteritis or severe stress, illness or trauma may trigger overt symptoms in this often latent disease.

In children, there may be a failure-to-thrive with stunted growth, behavioural problems and generally an ill child that may be prone to infections.

Infertility 

Coeliac disease is a common problem that is often not diagnosed and in fact, may be first diagnosed when an individual is in their 40's or older. These individuals simply accept how they feel and accept tiredness and feeling unwell as a part of their lives. A couple presenting with infertility should be assessed for gluten sensitivity and coeliac disease as this is a problem that could be resolved by simply avoiding gluten. 

Liver Disease & Coeliac Disease

1 in 20 [5%] of patients with advanced liver disease waiting for a liver transplant, may have undiagnosed coeliac disease. The sad part of this avoidable consequence, is that there is great potential for the liver to revert to normal if the individual was placed on a strict gluten-free diet.

It is critical that this diagnosis is not missed. It is important to note that the effects of this disease are insidious. In other words, the disease process will operate inconspicuously in the background of the lives of many of those suffering from coeliac disease the effects of which will slowly and inexorably lead to serious health problems.


Coeliac_Mechanism.png

Click to enlarge

Mechanism of damage

How are the cells of the intestine damaged

The precise details of the underlying immune response to gluten is yet to be elucidated. It is described as an immune system mediated disorder but is it an autoimmunity? [see Curr Opin Immunol. 2005 Dec;17(6):595-600.] Some of the known mechanisms are shown above.

“Underlying mechanisms in coeliac disease pathogenesis. Wheat gluten is partially digested but key toxic sequences are resistant to intestinal proteases. One gluten peptide (p31-43/49) may directly induce interleukin 15 (IL-15) production from enterocytes and dendritic cells but precise details remain unclear. IL-15 upregulates MICA, a stress molecule on enterocytes. Another gluten peptide (p57-73) is deamidated by tissue transglutaminase and is presented to T cells by HLA-DQ2 on antigen presenting cells. The initial triggering event occurs in the mesenteric lymph nodes but the importance of presentation in the mucosa is uncertain. Epithelial cytotoxicity occurs via at least two mechanisms: cytokine release (especially interferon γ (IFN-γ)) by antigen specific T cells and directly by intraepithelial lymphocytes via MICA-NKG2D interaction.”
(van Heel 2006)

Reference:
van Heel, D. and J. West (2006). "Recent advances in coeliac disease." British Medical Journal 55(7): 1037.

Genetic Predisposition

DNA-Viewe_XXS.jpg

People with coeliac disease do have a genetic make-up called the HLA-type. Genetic screening can be done in most laboratories now and this genetic screening is useful as a test to exclude coeliac disease or to test for susceptibility for coeliac disease.

HLA DQ2 & HLA DQ8

These tests are not actually helpful as a positive predictor for coeliac disease. Only approximately 1 in 30 individuals with these genes will actually have coeliac disease.

So the gene testing for the markers HLA DQ2 & HLA DQ8 cannot diagnose coeliac disease - these markers can only exclude it.

A first-degree relative of someone suffering from coeliac disease has a 10% chance of also having coeliac disease.

Dipeptidyl peptidase-4 (DPP4)

Rate-Limiting Enzyme in Gluten Digestion

DPP4-Enzyme-WikiPDxxsjpeg.jpg

This enzyme is found in the brush border of the intestinal wall and is indeed found on the cell surface of most cell types.

This enzyme is thought to be one of the rate-limiting enzymes with regard to the digestion of gluten. Theoretically, if enough of this enzyme activity was present through supplementation, then many individuals with non-coeliac gluten intolerance may benefit symptomatically.

Diet possibilities

Unleash the power of diet to prevent disease

Diet Choice

Individuals who are on a gluten-free diet, feel that they are on a healthy diet. This in fact may not be the case as gluten is a protein. Once protein is removed from the carbohydrate, the glycemic index [GI] of that carbohydrate increases.There are numerous adverse effects to consuming high glycemic index foods.

So the challenge of a gluten-free diet is to also provide low glycemic index choices or strategies to help lower the glycemic index of the gluten-free carbohydrate component.

NutriDesk meets this challenge head-on and provides you with detailed information on how to have a healthy, nutrient-rich diet designed with a view to promoting optimal health on a restricted diet. 


Irritable Bowel Syndrome

  • Individuals with bowel symptoms may not suffer from gluten intolerance but may have an intolerance to FODMAPs
  • Excluding FODMAPs in individuals suffering from a functional bowel disorder like IBS can make a world of difference.

Coeliac Disease Testing

US Celiac Disease

Test-Tubes-Coloured-xxs.jpg

ARL Pathology - click on the link on the right. If you have a chronic illness or if you are feeling constantly unwell, especially so if you have an inflammatory disease such as arthritis, heart disease, diabetes or asthma and chronic lung disease. Checking essential fatty acid status may just be that important step you need towards good health.

Testing takes the guesswork in terms of your dietary needs or supplementation.

Testing for Coeliac Disease

Serological Markers [Blood Tests

These should be the first-line tests for coeliac disease

  • IgA Level: IgA deficiency may occur in 1 in 300 people and needs to be tested to validate the IgA based tests [described below]
  • IgA Antigliadin: Negative 6-8 months after being on a gluten-free diet.
  • IgG Antigliadin: Negative 12-18 months on a gluten-free diet
    The IgG and IgA antigliadins are used more to monitor compliance of patients on a gluten-free diet.They are highly sensitive but less specific in detecting coeliac disease. High levels are invariably strongly positive in coeliac sufferers not on a gluten-free diet but low levels of these antibodies do not necessarily indicate disease.
  • IgA Endomysial Antibodies: Has high specificity for coeliac but on occasion is less sensitive. The test becomes useless in patients with low IgA level. With the new generation TTG test, the IgA Endomysial antibody test is thought to be redundant. 
  • TTG Antibodies - the main if not the sole autoantigen in coeliac disease. This test has very high sensitivity and specificity [although not perfect]. IgA-TTG antibody testing also becomes useless in patients that are IgA deficient.
  • Combined IgA-TTG & IgG-TTG Antibodies: Combined antibody testing is thought to be less likely to miss IgA deficient patients and to miss 'Picarelli' patients. 

Picarelli Patients

  • A small subgroup of patients were found to exist with biopsy proven coeliac disease but no evidence of IgA antibodies to gliadin, endomysium or TTG and these patients were not IgA deficient. The IgG-TTG antibody test will pick up these individuals.

HLA Genotype Testing

  • HLA-DQ2 HLA DQ8 These genetic markers are not used to diagnose coeliac disease as only about 1 in 30 people with these genes will have the disease. These tests are used to exclude coeliac disease.

Possible Tests to investigate [your potential for chronic inflammation]

Any disease state involving tissue injury and malnutrition may result in systemic inflammation. There are significant ramifications to background inflammation in the body including heart disease, many cancers, Alzheimer's disease etc.

  • The AA/EPA Ratio --- the Arachidonic Acid [AA] to Eicosapentaenoic acid [EPA] ratio is an early marker of inflammation. Recent studies have shown that individuals taking statin medications have have increased levels of the very inflammatory AA in their blood [Harris et al 2004].
  • The EPA/DGLA Ratio ---can be used to fine-tune the good [anti-inflammatory] Series-1 and Series-3 eicosanoids.
  • The Omega-3 Index --- this particular test is a major advance on assessing essential fatty acid testing as results are comparable between laboratories. This test measures the percentage of the omega-3 essential fatty acids DHA and EPA in erythrocytes [Red Blood Cells]. A good Omega-3 Index is regarded as being greater than or equal to 8. A 'healthy' Western population has an average Omega-3 Index of 4.9 +/- 2.1 and individuals with coronary artery disease [blocked heart vessels] have an Omega-3 Index of 3.9 +/- 1.1. [Curr Opin Nutr Metab Care 2008; 11[2]:94-91.

See References:

Link to QuickGuide References

Please register it's quick and easy.

There is no obligation. Just click on the following link: Join NutriDesk then you can access the references through the link below.

QuickGuide Topic References