Thank you for all of these helpful answers!  I really appreciate them. I typically eat 2 eggs every morning, so I'm going to stop those, in case the iodine is an issue. And, I'm checking all of my medications and supplements for gluten. I will try some of these other suggestions, too. Thank you all. I feel like I have a little bit of hope that this can get better soon.

Hi Leenora, thanks so much for sharing your journey. Yes, I am based in Ireland and I think the primary care docs should know better here. Like yourself my IGA was undetectable.  I do not have any major GI symptoms as a result my doc would only order total IGA as the next step and not IGG - so frustrating. I am ready to start a gluten free diet which will hopefully help with nutrient absorption and ultimately overall health. As someone who has already gone through a breast cancer journey I would like to be assured that my immune system is working optimally. My big concern is around Alzheimers as my Mom was diagnosed with Meniers at my age and developed memory decline in her mid 70s. She has an Alzheimer's diagnosis but her neurologist thinks it is more short term memory loss. Since neurological health is a concern of mine I have ordered the B vitamins recommended by kitty kitty on this thread. I have upped my VitD supplements and haven't had a vertigo attack in 2 weeks. I agree with your observation that these things are all connected - they likely are very much connected with gut health. I am also planning on ordering germline genetic testing to check my pre-dispositions. 

I would not be surprised if that is the case. I briefly took doxycycline and it cleared up but I also stopped eating oats at the same time so hard to say what did it. And I understand doxy is nasty stuff. I had to take it with yogurt because it messed up my stomach so badly. 

I would hesitate to recommend tetracycline or any antibiotic as a long term therapy option because of the negative impact it has on the gut biome. I took it for years as a teenager for acne and I'm convinced it was a contributing factor in my having developed celiac disease.

Welcome to the forum, @Pamp8, I stopped foods high in iodine, like dairy and eggs, kelp and iodized salt.   I take Niacinamide also called Nicotinamide or Vitamin B3.  I haven't taken the tetracycline with it.   It seems to make the blisters disappear quicker. I also use tallow balm, a cream made from beef fat, which has been used for thousands of years.  It is absorbed into the skin better than creams made from plants.  It helps prevent or lesson scarring.  See the study below. Two Cases of Dermatitis Herpetiformis Successfully Treated with Tetracycline and Niacinamide "The combination of tetracycline and nicotinamide can be recommended as a useful therapy for patients where dapsone is not available or for patients who do not tolerate dapsone." https://pubmed.ncbi.nlm.nih.gov/30390734/