I'm not confirmed as having CD, and I do currently eat gluten containing foods. I already have a thyroid autoimmune disorder diagnosed and have been struggling with poor health for last 2 years (primarily lethargy, insomnia, anxiety, weak muscles, poor memory/focus). I'd had low Vit D sorted out during that, and tried different thyroid doses, including ones with an alternate thyroid medication that I hoped might fully fix me but no luck, only small improvements.
Recently I'd had some luck with a new diet. I know I have an intolerance or allergy to rapeseed pollen and likely also to it in oil (often used in vegetable oil and fat) so I'd been eliminating that - the longer I go without it the better I'd felt but only managed at best 3 weeks. I did wonder though if I might have other food issues but tested by GP and not allergic to cows milk/eggs/peanuts/soya/cod. It did occur to me there was possibility this diet could have improved my health for what else it was cutting out, as due to vegetable oil in it I am rarely eating breads and now home cook most meals.
My GP did test for Coeliacs before with antitransglutimate tTg test last year, test negative I'm told, but from the reading I'd done online it was suggesting that test has only 85% efficiency and that in particular may report a false negative in patients with low IgA and that low IgA is more likely in patients with autoimmune problems. So, I personally do not feel satisfied in the face of symptoms that the Coeliacs issue is fully investigated, though my GP said they've done all they can. I suspect if I want to be sure about that I need to pay for private tests. I'm aware there about 4 or 5 that can be done but not sure what combination is best to get to thoroughly rule it out (or all of them to be sure?) nor where offers these tests without requiring GP approval.