A Quick Aussie Guide to Coeliac Disease

Coeliac disease is an autoimmune condition where your body reacts badly to gluten – a protein found in wheat, barley, rye, and oats. When someone with coeliac disease eats gluten, it causes damage to the small intestine.

Normally, the small intestine is lined with tiny, finger-like projections called villi. These villi help soak up nutrients from food. But in people with coeliac disease, gluten makes them inflamed and flattened. That means your gut struggles to absorb the good stuff your body needs – which can lead to all sorts of health problems.

And while gluten sounds like it’s just in bread, pasta and beer, it’s actually sneaky. Food manufacturers use it in a huge range of products, from sauces to lollies, which makes avoiding it tricky.

How common is it in Australia?

Here’s the surprising bit: around 1 in 70 Aussies has coeliac disease. Even more surprising? Roughly 80% of those people don’t know they’ve got it.

That’s why Coeliac Awareness Week (13–20 March, 2024) and International Coeliac Day (16 May) exist – to spread the word and help people recognise the symptoms.

If you’ve got coeliac disease, there’s also about a 15% chance you’ll have another autoimmune condition like arthritis, thyroid issues, Type 1 diabetes, or multiple sclerosis. The later you’re diagnosed, the more likely these complications can pop up – which is why early testing is so important.

Symptoms of coeliac disease

Coeliac disease isn’t always obvious – some people get hit hard with symptoms, others barely notice. But here are some of the more common red flags:

• Ongoing gut issues (bloating, diarrhoea, constipation, stomach pain)
• Tiredness or fatigue that won’t budge
• Unexplained weight loss
• Iron deficiency or anaemia
• Mouth ulcers
• Skin rashes
• Irritability or mood changes
• Poor growth in kids

If that sounds like you (or your child), it’s worth chatting to your GP.

How do you get tested?

Step one: keep eating gluten. Yep, you read that right. If you cut gluten before testing, your results might come back inaccurate. If you’ve already ditched it for more than six weeks, your doctor may ask you to do a gluten challenge (reintroducing gluten before testing).

Step two: blood test. Your GP can order a blood test (called coeliac serology) to check for certain antibodies linked to coeliac disease. These usually include Transglutaminase-IgA (tTG-IgA) and Deamidated gliadin peptide-IgG (DGP-IgG). A positive result doesn’t confirm coeliac disease, but it’s a strong sign to see a gastroenterologist.

Step three: small bowel biopsy. This is the gold standard for diagnosis. A gastroenterologist will do a gastroscopy (day procedure under sedation) and take tiny samples from your small intestine. These biopsies are checked under a microscope to confirm whether gluten is causing damage. For kids, sometimes a biopsy isn’t needed – a paediatric gastroenterologist will decide based on specific criteria.

Gene testing (HLA genes)

Another option is a gene test that checks for the coeliac-associated genes (HLA-DQ2 or HLA-DQ8). You have to carry one of these genes to develop coeliac disease, but having them doesn’t guarantee you’ll get it.

A negative gene test rules coeliac disease out completely, which can be handy if your diagnosis is unclear. A positive test just means you could develop it, so further testing (including a gluten challenge and biopsy) may be needed.

A word of warning on dodgy tests

You might come across all sorts of alternative tests online or at “wellness” clinics claiming they can diagnose food intolerances, including coeliac disease. Be careful. Many of these are unscientific, misleading, expensive, and can delay proper treatment. Stick with the tests recommended by your GP or gastroenterologist.

Final note

If you suspect coeliac disease, don’t jump straight onto a gluten-free diet before proper testing – you could make diagnosis harder. Get tested, get answers, and if it’s coeliac disease, a specialist will guide you on living gluten-free the right way.