Negative celiac bloods but persistent blistery rash

[Rosie82]

I suddenly got itchy skin a year ago. Started on inside forearms- would get pimple like rash. Spread to arms and legs that would look like hives with wee blisters. Intensely itchy!! Also elbows, stomach, lower back and sometimes fingers.

Dermatologist first put me on 6x antihistamines a day for 2months- no difference. Then did bloods for Celiac which came back negative.  He now has me on the immuno suppressant, Azathioprine. Have been on for nearly 2mths and has improved - still get wee outbreaks on my legs and itchy arms etc at night. Dont like the idea staying on Azathioprine long term..

Is it possible it could be DH eventhough bloods negative? Dermatologist has no idea of the cause and tbh not many specialists bother investigating causes anymore. From what I can see Azathioprine gets prescribed for a lot of auto immune skin conditions- a good back stop for mystery rashes...

Worth going gluten free? How long would you recommend for? 

Thanks

[trents]

Welcome to the forum, Rosie82! Yes, it is possible to have DH with negative blood antibody test scores. A small percentage of those with DH do not have GI involvement. 

What I would suggest is that you have your skin biopsied during an outbreak. Find a dermatologist who knows about celiac disease/DH and who knows how to do a proper skin biopsy to check for DH. My understanding is that the biopsies need to be taken from the skin adjacent to the bumps rather than from the bumps themselves.

By any chance had you already started a gluten free diet before the "bloods" were done. If so, that would invalidate the antibody tests.

Also, do you know which antibody tests or tests were deployed?There are a number of celiac antibody tests that can be run but many physicians will only run the tTG-IGA, at least initially. Can you post the test names along with reference ranges for negative vs. positive thresholds?

Edited October 29, 2023 by trents

[Rogol72]

I agree with trents. I believe you can have DH with negative bloods. I was on Azathioprine for UC at the time I was diagnosed with DH, and partially eating gluten free to treat the UC. I don't recall if a Coeliac panel was conducted. From what I understand the Coeliac antibodies in the blood are TTG2 while the skin antibodies are TTG3.

Rather than going gluten free, I would strongly advocate for a skin biopsy to test for DH from a Dermatologist who has seen it before as trents indicated. DH blisters usually appear at pressure points on the skin ... so the knees, elbows, hips, hairline etc. and on both sides.

[Wheatwacked]

Posted October 10, 2012 · Am I the only one who suffers the most at night. I can feel skin layers peeling off under my nail. My skin is burning and stinging and itching all at the same time.  Night Time The Worst

It is very likely that you have low to deficient vitamin D in your blood.  Raising it will help your compromised immune system.

8 hours ago, Rosie82 said:

Worth going gluten free? How long would you recommend for? 

The good news: patients with DH overall have a lower mortality rate compared to that of the general population when on a GFD. 

         Dermatitis Herpetiformis: An Update on Diagnosis, Disease Monitoring, and Management 2021  "If a patient with high clinical suspicion for DH displays a negative DIF result, clinicians should consider repeating the exam with a biopsy from a new site of normal appearing perilesional skin. False-negative results occur in about 5% of biopsies...  38% of their biopsy proven DH patients were negative for both TG2 and EMA... A strict GFD can decrease IgA levels in the skin, also affecting DIF results in contrast to pharmacologic treatments which do not alter IgA deposits. "...patients with DH may have a history of GI symptoms such as bloating, diarrhea, or constipation, but these are usually minor if present... Although it is possible to return to a normal diet without relapse in 20% of cases, the effects of this change on long term morbidity and mortality are not known.  As of now, there are no guidelines for transitioning well-controlled patients to normal diets, and it is prudent for all patients with DH to maintain a lifelong GFD to achieve optimal prognosis... However, a recent study found that 95% of DH patients that were well controlled on long term GFD, relapsed with a gluten challenge. Following or concurrent with diagnosis, clinicians should assess patients for malabsorption and associated autoimmune diseases. "

[Scott Adams]

If you have DH you will likely also want to avoid iodine, which is common in seafoods and dairy products, as it can exacerbate symptoms in some people. This article may also be helpful:

 

[Rosie82]

Thanks very much for your reply's!

No, I didn't receive the blood results so not sure what the levels are..

Unfortunately where i am in New Zealand there is only 1 dermatologist to see and that's paying privately too. He didn't want to do a biopsy..but will ask again next follow up.

My wee blisters are only on lower legs and once on finger..

Rash on elbows but not blisters..

Might just try gluten-free and see if helps.

Thanks for your advice 

[Scott Adams]

If you don't plan to do more testing for celiac disease and/or DH, then trying a gluten-free diet makes sense. If you do plan on more testing then you may want to wait until all testing has been completed. Most tests for celiac disease and DH require you to be eating gluten daily in the weeks leading up to the tests.