Chronic Rashes Need Allergy Detective Work

In my 20 year career as an NYC allergist, I am used to seeing difficult and frustrating rashes that drive patients to tears. Usually, my dermatology colleagues have seen these patients first and prescribe cortisone creams and antihistamines. When this doesn’t work, it’s off to see the allergist. Rashes fit into 2 broad categories: rashes that look like hives (the medical term is urticaria) and flat, red rashes. Chronic hives are often debilitating because they are so itchy and uncomfortable. Antihistamines will usually give some relief but again, in the tougher cases, oral cortisone is usually needed. It can’t be done for a long time because of side effects. This is where the expertise of a NY allergist comes into play.

The mystery about rashes, especially hives, is that the answer is below the surface of the skin. Chronic hives can be due to a food allergen the patient is consuming on a daily basis and not even be aware that it is aggravating the condition. As a food allergy specialist, I order specific tests to identify which foods might be triggering an allergic reaction. In my book, Dr. Dean Mitchell’s Allergy and Asthma Solution (Marlowe 2006), I wrote about a person who ate hot dogs and sauerkraut, and it took her months before she realized she was allergic to sulfites, an ingredient found in high quantity in sauerkraut.

The thyroid is an internal organ that has been linked to chronic hives. It’s not well understood, but when the thyroid is over or underactive the dysfunction can manifest itself with skin rashes, such as hives. I order special antibody tests for the thyroid to determine if there is a connection between the hives and the thyroid. If the tests are positive, I will then order a thyroid Ultrasound to see if any nodules are present. This a simple, painless test that only takes a few minutes, but offers clues to the condition.

I read some interesting reports linking Celiac Disease and chronic urticaria. I have seen several Celiac disease cases in my career as an allergist. Patients present with stomach problems and think it is a food allergy. Instead, after careful testing, I discover there are no specific food allergies, but the patient has an immune reaction to gluten products. Celiac disease today is even more common than we realize: 1 in 300 people suffer from this condition. The most deceptive part of this disease today is that many patients don’t have any gastrointestinal symptoms, and instead present with sinus disease, arthritis, anemia, and rashes. I am an avid tennis fan, and I suspect Novak Djokovic, the number 2 player in the world, may have Celiac disease. He mentioned in Sports Illustrated that he now eats a gluten-free diet and feels his energy is much better. The gluten-free diet is not an easy diet to follow in our society, but there are many supermarkets that now have an array of gluten-free products that offer many new options.

Going back to the flat, red rashes, good allergy medical detective work is needed. I recently treated a patient with severe redness on his face and all over his hands. Allergy Patch testing (without needles) was done and revealed he was allergic to his hair dye. Another patient developed a painful rash on her legs. A painful rash is usually not allergic – it turns out she had cellulitis (an infection with bacteria of the skin).

The summer is upon us – with a lot more skin exposure. My advice to all: get 45 minutes of sun exposure to raise your Vitamin D levels, wear sunscreen after that and especially on your face. If you do get a rash that persists more than a day or two, make sure to see a physician.

Dr. Dean Mitchell
Mitchell Medical Group, NYC & Long Island