MYSTERIOUS RASH: COULD IT BE A FOOD ALLERGY? (PART 1)
I’ve been looking forward to writing this post for some time- it’s the real reason I wanted to start a blog. Eczema, a common rash that can be linked to food allergies, is a diagnosis that while sometimes severe (it's miserable!), is not life-threatening nor a sign of other illness. For this reason, it seems often doctors treating eczema are quick to prescribe toxic topical creams bearing both short term and long term side effects, a temporary mask for chronic symptoms rather than a real solution. Three friends recently messaged me seeking advice- two mothers with new babies (one a newborn, the other 6 months old and starting solid food) who were both prescribed hydrocortisone cream for mysterious rashes, and a third whose husband has been battling an ongoing rash with unknown cause as well. If you, your child, or someone you love is enduring a chronic and mysterious rash, of course it’s best to see a doctor right away- some rashes are indicative of serious illness. Here I share with you my own experience with severe and chronic eczema, how my rash was diagnosed, treated and ultimately banished!
When I developed a mysterious and severe rash at age 30, first on my eyes, then armpits!, neck, later my torso, legs, hands, and mouth, I was desperate for answers. The rash would come and go daily, seemingly at random, and as I waited for test results that would turn up negative at the Allergist and the Dermatologist departments at Yale, I scoured the internet commiserating with people of all ages in strange chat rooms, sharing poorly written descriptions of itchy and painful symptoms typed in wee hours, bizarre trial and error efforts, rare triumphs and many defeats. I read plenty of misleading info along the way. Even highly reputable sites to this day contain advice that conflicts with what I learned from the head of the Allergy department at Yale, and ultimately his insights proved accurate in my case. I had to piece together the puzzle over an intense year of chronic suffering. If only I had found in a single article or from a single doctor's appointment all of the key answers I needed. I have a wealth of information to share with you from my personal experience and success in hopes that it might help you solve your own mystery and get some fast and lasting relief. In this 3-part post, I’ll summarize those key answers I mentioned, and I’ll follow up with a series of additional posts on skin health and skin care in the coming weeks.
1) WHAT IS ECZEMA?
According to the National Eczema Association, there are 8 different types of eczema, each type characterized by various differences in appearance (small blisters or bumps, circle ‘coin’ shaped patches, flaky or peeling skin, cracked scaly skin, dark red skin, thickened skin, swelling, burning or tenderness etc… detailed descriptions can be found on their website. For the purpose of giving a broader introduction to eczema in this post, I’ll focus on Atopic Dermatitis and Contact Dermatitis, as these are the two that I’ve experienced. (My atopic dermatitis is caused by allergy to legumes, including soy, and flares up when I ingest the tiniest amount of these allergens. My contact dermatitis occurs when my skin comes into surface contact with soy, which lurks in topical products like shampoos.)
The Mayo Clinic definitions are below:
Atopic dermatitis is a condition that makes your skin red and itchy. It's common in children but can occur at any age. Atopic dermatitis is long lasting (chronic) and tends to flare periodically and then subside. It may be accompanied by asthma or hay fever. No cure has been found for atopic dermatitis. Atopic dermatitis (eczema) signs and symptoms vary widely from person to person and include:
- Itching, which may be severe, especially at night
- Red to brownish-gray patches, especially on the hands, feet, ankles, wrists, neck, upper chest, eyelids, inside the bend of the elbows and knees, and, in infants, the face and scalp
- Small, raised bumps, which may leak fluid and crust over when scratched
- Thickened, cracked, dry, scaly skin
- Raw, sensitive, swollen skin from scratching
Contact dermatitis is a red, itchy rash caused by a substance that comes into contact with your skin. The rash isn't contagious or life-threatening, but it can be very uncomfortable. Contact dermatitis usually occurs on areas of your body that have been directly exposed to the substance — for example, along a calf that brushed against poison ivy or under a watchband that triggers an allergy. The reaction usually develops within minutes to hours of exposure to an irritating substance or allergen. The rash can last two to four weeks. Signs and symptoms of contact dermatitis include:
- Red rash or bumps
- Itching, which may be severe
- Dry, cracked, scaly skin, if your condition is chronic
- Blisters, draining fluid and crusting, if your reaction is severe
- Swelling, burning or tenderness
The severity of the rash depends on:
- How long you're exposed
- The strength of the substance that caused the rash
- Environmental factors, such as temperature, airflow and sweating from wearing gloves
- Your genetic makeup, which can affect how you respond to certain substances
It’s important to note that while atopic dermatitis can appear virtually anywhere on the body, it’s location is irrelevant to the cause of the rash. This is unlike contact dermatitis, in which the rash appears only on an area of skin that came into direct contact with an allergen. This can be confusing when you’re doing detective work to determine the cause of your rash. In my case for example, my doctors first guessed that my rash was from a contact allergy to deodorant or makeup because the rash appeared only on my eyelids and underarms. Later when the rash appeared on my hands, torso, behind the ears, legs etc, doctors still considered that a contact allergy could be possible, perhaps in response to a detergent or chemical in my clothing. When the rash became the worst on and around my mouth with severely swollen lips, the dermatologist remarked that there could be a likelihood of food allergies at the root of all of my eczema afterall.
2) CREAMS AND MEDICATIONS
Steroid creams and antihistamines will provide effective relief of symptoms, but so long as you’re exposed to your allergen, eczema will reappear immediately once you stop medication. There are no medications that “cure” eczema. According to my doctor, eczema was once thought to be a symptom of an underlying emotional issue, or caused by stress, and he explained that this theory has been debunked and termed outdated. As eczema is an inflammation in the skin, absolutely anything, even just plain water or a change in temperature, can easily irritate and change the appearance of eczema at any time. The first key in solving the mystery of my own chronic rash was when my doctor said simply “Eczema is always a symptom of an underlying allergy." Identify the allergen, remove exposure to the allergen, and watch your eczema disappear for good.
Image of some mild hand eczema and how it has changed in appearance over the last 8 months since I accidentally consumed a tiny bit of soy in a restaurant while traveling last summer
3) GENETIC PREDISPOSITION AND THE ONSET OF ALLERGIES
We are predisposed to allergies through genetics. You may have a parent or sibling with an asthmatic reaction to environmental allergens like pet dander or tree pollen, while your allergies may be to foods and manifest as eczema. Allergies can develop slowly or suddenly at any age in life without specific cause. Some babies and young children suffer from allergies that they later simply outgrow as their bodies develop. Overexposure to a substance can lead to the development of an allergy (in my case eating an abundance of soy daily and using soy based vegetable oil in my art studio as a cleaning solution likely contributed to my adult onset soy allergy).
4) TYPES OF ALLERGENS THAT CAN CAUSE ECZEMA
While eczema is always a symptom of an allergy, the allergy can be to any number of things: foods, environmental allergens (pet dander, dust mites, tree pollens etc), chemicals found in household and personal hygiene products (soaps, deodorants, detergents), in cosmetics (hair products, nail polish, makeup), in fabrics (clothing, upholstery), rubber (the soles of your shoes), metal (nickel in coins or jewelry), paints or finishes etc.
5) ALLERGY TESTING
Once you’ve been diagnosed with eczema, it’s wise to ask your doctor about allergy testing as a first step towards identifying your allergen/s. There are a few various types of allergy testing available, and your doctor will choose what is most appropriate based on a number of factors. Two common food allergy tests are done through an allergist’s office, and they are a skin prick test, and a blood test. The skin prick test involves pricking the skin with a teeny tiny needle to in essence inject the skin with minuscule amounts of selected allergens. Suspected environmental allergens and food allergens can be tested in this manner. The skin is observed in the office for signs of inflammation and reaction. Typically babies and toddlers are not subjected to the skin prick test, nor are older children or adults who have severe eczema (as I did). A blood draw is used instead in these cases so as to avoid creating further symptoms in the patient. Potential allergy to chemicals can be tested using a “patch test”, in which a series of selected allergens are rubbed onto the skin (the back) with cotton balls in gridded squares, and a small bandage or patch is placed over each test site while a patient waits overnight at home to observe any reaction. Unfortunately, as my allergist explained, food allergies in particular are very difficult to test accurately. It is more common than not to see false positive and false negative results in the case of food allergy testing. While you may suspect food allergies are the cause of your rash, testing is a good start to rule out environmental and chemical allergens and offer some possible insights, but it often does not provide the ultimate answers. Another type of testing called an “oral food challenge” is offered in cases in which there is concern the patient could have a life threatening reaction, anaphylaxis, in which the airway constricts. Food challenge testing is done in the safety of the allergist's office, and a minuscule amount of the food protein is very slowly introduced to the patient in carefully measured and increasing increments, waiting and watching for reactions throughout the process.
In my case, I tested negative to chemicals, negative to foods in both a skin prick and blood test, and positive to only a few environmental allergens that I was already aware of, and which were clearly unrelated to my ongoing eczema. My food allergy symptoms, at their worst, included redness of the skin around the eyes and swollen eyelids, eczema on my hands, face and body, and extreme swelling of my lips. Ultimately I would eventually learn that I was allergic to soy protein, which I was eating unknowingly in every meal of everyday, and applying to my body topically via shampoos, soaps and makeup. A good resource for up to date information on food allergies and testing is the Food Allergy Research & Education website: http://www.foodallergy.org/diagnosis-and-testing
6) HOW FAST DOES A REACTION OCCUR AND HOW LONG DOES IT LAST?
Eczema can range from mild to severe, and regardless of the severity, the reaction may occur within minutes of exposure to your allergen, or delayed by a few hours. I would eventually learn that my reaction to soy protein is delayed by about 2 hours after contact or ingestion. Eczema is long lasting. A single encounter with an allergen can cause eczema that lasts days, weeks, or even months. These time tables easily add confusion when you’re trying to determine the cause of your rash. Because I was unknowingly consuming and contacting my allergen (soy) everyday throughout the day, and because my reaction was delayed by 2 hours, I generally had eczema on my body all of the time, but it would seem to randomly worsen at various times throughout the day, surely 2 hours after I had eaten or contacted more soy products. The chronic rash made it nearly impossible to isolate the cause and effect connection and timeline.
*Please stay tuned to PART 2 of this post on eczema, which I’ll share later this week. I’ll discuss the most common food allergens, and the elimination diet that ultimately solved the mystery of my rash and helped me clearly identify my allergens once and for all. I’ll also discuss babies and toddlers with dairy allergy, and how to safely navigate breastfeeding with food allergies.