Nafsika, the diagnosis of coeliac disease can be quite complicated. If you are concerned, your GP can organise for your child to have some initial blood tests. These look at both specific and non-specific immunological activity. Coeliac disease is an auto-immune disease...the body "attacking itself" in an abnormal way, in the presence of gluten (typically found in wheat).
The diagnosis of coeliac disease requires an endoscopy; so, tiny samples of the small intestine taken and examined under a microscope. The scientist looks for certain classic characteristics of the tissue specimen, to assist with a true diagnosis of coeliac disease.
It's important NOT to start a gluten-free diet before confirming the diagnosis, as this can interfere with making a correct diagnosis. It can make it look like a patient doesn't have/has less severe coeliac disease than they actually do.
So, a GP can initiate blood tests, and then organise a referral to a Gastro-Enterologist. This can be done through the public system.
Coeliac disease is a serious disease, and it's important not to get caught up in the "gluten-free w@nker movement". Which I'm sure you're not.
Hope this helps.
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