Diagnosing Coeliac Disease

Coeliac disease is an autoimmune disease causing damage to the small intestine in response to eating gluten (the protein portion of wheat, rye and barley). In Australia 1 in 70 people are affected with 4 out of 5 Australians with Coeliac Disease being undiagnosed.

Signs and Symptoms of Coeliac Disease

  • Fatigue

  • Nutritional deficiencies, particularly Iron and Calcium

  • Weight Loss

  • Mouth Ulcers and dental enamel defects

  • Premature osteoporosis

  • Problems with liver function tests

High risk categories for Coeliac Disease

  • Those with another Autoimmune Condition eg: Thyroid disease, Type 1 diabetes, Addisons disease, Sjogrens syndrome, autoimmune liver disease

  • Dermatitis herpetiformis

  • Downs Syndrome

  • Turners syndrome

Whist many of those with Coeliac disease are seemingly symptom free, a major symptom is the damage being done to the small intestine, the vili in the slinign of the small intestine (small bowel) where nutrients are absorbed.

Treatment is via a lifelong Gluten Free Diet.


If your doctor suspects you may have Coeliac disease based on your symptoms, and you are eating gluten, a Coeliac blood test will be arranged. If this blood test result is either low or negative and as long as Gluten is being consumed (around 2 slices of bread per day or 2 weet bix for the 6 weeks leading up to the test), Coeliac Disease will be excluded.

A strong positive test will lead to a small bowel biopsy being completed. If the biopsy demonstrates damage to the villi in the small intestine, the diagnosis of Coeliac disease will be made in which case a Gluten Free Diet is the only treatment.

Should the result be normal tissue with no obvious damage to the villi or a poor sample of tissue not demonstrating the extent of the damage, further review and possible further testing will be required.


A gene (the HLA DQ2/8) has been associated with Coeliac Disease. In cases where a patient is unable to complete a blood test whilst gluten challenged, a gene test might be completed. 99% of people with Coeliac Disease have the associated gene. Unfortunately the gene is also present in around 40-50% of people who don't have Coeliac disease. This means that a negative test will exclude you from a diagnosis of Coeliac Disease.

1. Coeliac Australia (2015), Diagnosing Coeliac Disease - the key facts., www.coeliac.org.au

2. Tye-Din JA ((2018), Interpreting tests for coeliac disease: Tips, pitfalls and updates, AJGP, Jan-Feb, 47(1-2)