I'm new here, but I've been reading this forum for a while. I'm seeing my doctor in two weeks to discuss celiac testing. I'm 37 years old and have had many, many symptoms for my whole life and was given a lot of misinformation whenever I asked previous doctors about celiac or food allergy testing. (One doctor told me that I'd have died as a child if I had undiagnosed celiac, and that it was a ridiculous idea and she'd never order the tests. Another doctor said that the incredibly itchy rash covering my entire torso, which I had for years on end, did not require further investigation and would go away as soon as I "stopped worrying about it so much".) I finally have a doctor who seems willing to take my concerns seriously, and I want to make sure my test results are as accurate as possible.
I've gotten mixed results with food allergy tests. I had clear positive skin pricks for wheat and several other foods, but negative blood allergy tests for those same foods. On my skin pricks, I had very large red flares around half the fruit and vegetable prick sites but no wheals; this was considered negative, but it was unusual and didn't just indicate general skin irritability because the saline control spot and half the others had no flare. Anyhow, the allergist concluded that I did not have a wheat allergy because of the negative IgE test, and she said the positive skin pricks were just from cross-reaction to environmental allergens (which I know I have). I'm not entirely confident about that assessment, but I've had so many weird and inconclusive test results for various things over the years that I'm used to it.
I stopped eating wheat after the allergy tests anyway, and within days many of my long-standing problems were definitely improving. After several weeks I started eating a little wheat again while taking antihistimines, and the symptoms returned. My stomach bloated up even more than before, and it looked like I was six months pregnant just from one meal of wheat. Having this reaction while on antihistimines seemed like pretty clear evidence that a wheat allergy alone (if indeed I have one) couldn't be the whole problem. At that point I switched to a new primary care doctor and started eating small amounts of wheat again every day because I want the celiac tests to be accurate.
My immediate question is about the effect that small amounts of topical cortisone cream or a one-time pill dose of prednisone might have on celiac blood tests or an endoscopy.
I've been using a tiny dab of cortisone cream on a rash spot on my face every day. It doesn't make the rash go away, but it makes it less red. I can do without it, but it's a tiny amount and the rash is embarrassing because it's so visible on my face. Should I stop using it completely? For how long?
Also, I get monthly allergy shots for environmental allergens, and after an full year on the maintenance dose my whole arm still swells up hugely after the shot unless I take two antihistimines and one prednisone pill first. I started to have breathing difficulty after the shot without the prednisone once, and it was scary so my allergist said to just routinely take the predinose on shot days from now on. I can take up to four doses on prednisone if needed, but I've never needed more than two and I'm willing to stick to just one even though it means dealing with the swelling longer. However, I'm very nervous about doing the allergy shot without that one dose. I do have an epi-pen and could treat myself for anaphylaxis until I got to a hospital, but that's the last thing I need right now! If I go more than 42 days between shots, the whole five-year process becomes invalid and I'd have to start all over again. My environmental allergies are pretty severe, so I really don't want to abandon the process. I can try to schedule the celiac tests so they're as close as possible to the 42-day cut-off since I've last had prednisone, but will one dose of prednisone five weeks earlier make the test results invalid? And do steroids affect blood test results too, or just the endoscopy?