Welcome to the second episode of our podcast series, “Atopic Dermatitis In Skin of Color.” The podcast series examines the importance of diagnosing, managing and treating atopic dermatitis, or eczema, in people of all skin colors. This episode is “Diagnosing Atopic Dermatitis in People of All Colors.”
The podcast is a joint collaboration between Allergy & Asthma Network and The Itch Podcast led by co-hosts Kortney Kwong Hing and allergist/immunologist Payel Gupta, MD. In this episode, Kortney and Dr. Gupta once again welcome special guest and social media influencer Shiv Sewlal.
You can also listen to or download the podcast on ItchPodcast.com for listening anytime, anywhere. The podcast can be downloaded at:
In this Episode…
1:19 – An overview of what eczema looks like in people of color
3:26 – Skin conditions that can lead to misdiagnosis or delayed diagnosis of eczema
5:25 – Symptoms of eczema that can lead to an accurate diagnosis
6:25 – Shiv Sewlal discusses how she was diagnosed with allergies and eczema
9:18 – What is an IgE test?
12:55 – The importance of having a trained doctor interpret IgE test results
15:10 – How do skin prick tests work?
17:20 – Patch testing for reactions to soaps, cosmetics and other irritants
19:38 – When the diagnosis is difficult: skin biopsies
20:48 – Sharing your medical history and communicating with your doctor
Kortney Kwong Hing: You’re listening to The Itch, a podcast exploring all things allergy, asthma and immunology. I’m your co-host Kortney, a real-life allergy, asthma and eczema girl.
Dr. Gupta: And I’m your second co-host, Dr. Payel Gupta, a board-certified allergy, asthma and immunology doctor. Kortney and I hope to balance each other out so that we get you all the information that you want and need about allergies, asthma and immunology.
Kortney: Welcome back, everyone. This is part two of our five-part series on atopic dermatitis and skin of color in collaboration with Allergy & Asthma Network. Today we’re going to cover how AD is diagnosed. If you missed part one, you can catch it now. We talk about why it’s important to raise awareness about atopic dermatitis and skin of color and how AD – which by the way, is how we’re short-forming atopic dermatitis, so you’ll hear AD a lot. And we also talk about how AD presents in patients with skin of color in part one. So check that out if you haven’t.
And I’d say let’s just jump right into it. So Dr. G, can we quickly go over what eczema looks like in skin of color for our audience who may have missed the first episode in the series?
Dr. Gupta: Yes, definitely. So in black or brown skin, eczema appears as dark brown, purple or ashen gray patches. It may also show as small bumps called papules, especially on the chest, back, arms and legs. And sometimes the bumps can grow around the hair follicles. And this can look like goosebumps and can cause the skin to get thicker and firm around that area and in turn cause the hair to almost stick up on its end. So some people notice that. And then repeated scratching of affected areas can result in thickening or firm skin called lichenification. And that’s a term that we use medically. And then it can also cause raised bumps called Prurigo nodules. So this is more common in patients with skin of color.
We also have linked images to the show notes for everyone so that you can see pictures of what we’re talking about. In addition, we spent a lot of time talking about this on the last episode, but it’s really important to mention again, because it can cause a lot of stress and anxiety for patients: in patients of skin of color, we see more skin discoloration called hyperpigmentation or darkening of the skin, and hypopigmentation or lightening of the skin. And this results from the inflammation and the post-inflammation irritation of the skin, and then also sometimes from the medications. So there are various reasons that we can get this hyper- and hypopigmentation. Regular treatment usually helps resolve skin discoloration and also helps to prevent it from happening in the first place. But it can take months or even years for it to go away completely.
Kortney: Great. Thank you for that quick summary. And again, you can get all the details in part one of the series. So before we get into the details of diagnosis and the tests used, it’s important to note what gets ruled out as other skin conditions. What we’re interested in knowing, Dr. G, is what are those skin conditions that may look like atopic dermatitis and things you might actually get misdiagnosed with?
Dr. Gupta: Oftentimes, especially in skin of color, people are misdiagnosed to have other skin conditions which can actually delay the diagnosis of atopic dermatitis in this population. That’s a really important concern. So as a result, people can experience symptoms and not get the right treatment due to the misdiagnosis or delay in diagnosis. And as we talked about, not treating the skin can then lead to that hyper- and hypopigmentation, which can cause a lot of stress and anxiety. So it’s really important for us to get to the diagnosis early.
Other skin conditions that may appear to be eczema or have similar symptoms to eczema include psoriasis, scabies, hives, ringworm, acne, cutaneous T cell lymphoma, Netherton syndrome, hereditary angioedema or chronic idiopathic urticaria. We won’t go into all of these conditions, but the treatment is similar to eczema for some of these conditions and very different for others. I think the important take-home message is to know that as a patient, if a treatment isn’t working for you, then the diagnosis might be wrong. And if you aren’t already seeing a specialist, it may be time to see one.
Kortney: Now, that’s really important to note that if you have had a diagnosis but the treatment isn’t working, it actually might be that you’re misdiagnosed. So thank you for saying that. I definitely know that my eczema looks like acne, but it’s acne that shows up in really weird places in the body. So it’s definitely not acne, it’s eczema. So I can see how that can get confusing for certain people. We’re also wondering, are there other ways that doctors know it’s atopic dermatitis and not something else? So how do they differentiate the two?
Dr. Gupta: It’s a conglomeration of symptoms, history, and what we’re looking at on the skin. And so common eczema symptoms that help to confirm the diagnosis can include intense itchy, skin swelling; dry, cracked, scaly skin; skin that feels warm when touched; and then open, crusty or weepy sores. Again, all of these things can happen in multiple conditions, but with the right history and with the right clinical picture, we use all of these things in conjunction to make the final diagnosis of eczema.
Kortney: I think now we’re ready to really launch into how you get tested and how a diagnosis happens for eczema. And we wanted to start with a story. So, as you may have noticed, we have Shiv Sewlal joining us throughout the series and she’s sharing her personal story of atopic dermatitis and skin of color. And you might know Shiv from Instagram or TikTok. We’re going to start with a little clip from her where she talks to us about her diagnosis and how it started as a baby.
Shiv: I was diagnosed with eczema when I was a baby, but it only became severe when my parents started introducing new foods to me as a toddler. My dermatologist at the time sent me for IgE blood tests to test for any allergies, and that’s where we realized the reason for my flares. I have a life-threatening allergy to peanuts and many other allergies that cause vomiting, swelling, etc. But most of my allergies caused eczema flares.
Growing up, I’ve always known that my allergies were linked to my eczema flare-ups, but it was extremely difficult to manage because of environmental allergens such as pollen, dust, animals and mold, which would constantly affect my eczema. I’ve been to many specialists – dermatologists, pediatricians, pulmonologists, etc. – throughout my life, but I’ve only ever been to an allergist when I was 20 years old. And I had to fly across the country to see her, because in South Africa, where I live, there are not many allergies. She really helped explain the link between my allergies, asthma and eczema.
Dr. Gupta: So these comments by Shiv are super helpful to point out a couple of things. First, not all eczema in babies is caused by foods, and in fact, testing isn’t always recommended for foods right away unless there is a noticeable link between eating the food and the symptoms of eczema. In babies with eczema, we can get what we call false positive results on food allergy testing because oftentimes their IgE levels are very high. And then everything on the test looks like it may be an allergen and it may lead to an unnecessary avoidance of foods.
We know that avoiding foods early on can actually lead to developing food allergies. So we definitely don’t want to do that. It is a hard balance depending on the age of the baby which food they have been introduced to. We need to take a careful history to determine if in fact there is a link to foods before we start testing. And I would also recommend not getting over-tested on all foods, even if you do think that there may be a link, because again, it can lead to misdiagnosing food allergies and unnecessary avoidance habits that can lead to further issues.
What I mean by that is just testing the particular foods that you’re actually worried that there might be a link to, and not over-testing – and testing for every single food when you are worried about a link. So that being said, eczema in babies can be caused by foods and it is important not to miss it if it is truly a trigger.
Kortney: Now, let’s really get into the testing side of it, because you and Shiv both mentioned IgE tests, which I would love to start with. So can you tell us about an IgE test and how that works in eczema?
Dr. Gupta: First, I want to note that the diagnosis of eczema is the same for all skin colors. Your doctor may look for allergens and irritants that can trigger a patient’s eczema. And some of these triggers are things like cosmetics, soaps, wool, food, pollen, mold, dust mites, dog or cat dander, stress, dry climate. Those are all the triggers. And then we’re going to talk about the different types of tests that we can do. So patients can undergo testing to find out which of these allergens or irritants are worsening their symptoms. Knowing what those triggers are for your eczema puts you one step closer to reducing your symptoms, whether it’s through avoidance, medication or other treatments.
So we’re going to review all the tests that are done to figure out which irritants might be causing our symptoms. So IgE testing is a blood test. The blood is taken at a lab and then it is analyzed to detect IgE antibodies. And that in particular will help us figure out if you’re allergic to environmental allergies or food allergies. When we have IgE antibodies detected on testing to specific allergens, then that means that the body will trigger a reaction to these allergens that causes the release of histamine. That leads to various symptoms depending on the person and the type of allergens.
So we always measure a total IgE level to see what your overall IgE levels are. This helps the doctor to interpret the testing more accurately. Sometimes, as I mentioned, eczema can cause your overall IgE levels to be elevated and the result of the blood test may get altered when this happens because all of the values to specific allergens will also look high when your total IgE level and your body is high. So that might be confusing for people, but that’s really for the doctor to understand. But I’m just mentioning that partly what happens is that the IgE, when it’s really elevated, the machine that calculates these values gets confused. And as a specialist, I’m used to looking at these numbers and can help decipher when it’s truly an allergen or not. But other physicians might not have that understanding because they don’t see the test as often. So that’s why it’s important not to look at the numbers on your own.
In addition to IgE testing, there’s also component testing for foods, which we have for certain food allergens like peanuts, milk, eggs and tree nuts, for example. And these tests can help your allergies further to see if the food is really the culprit of your symptoms.
Component testing is also a blood test. I won’t go further into explaining it unless you have questions.
Kortney: I’d say we can stop there with component testing, because it’s actually very interesting, but it’s quite complex and we have an episode about it. So if someone is interested in knowing more about component testing, you can check out episode 42 called, “What are Cross-Reactive Allergens.” It is really interesting because it’s amazing what we can do with blood tests.
Before we move on, I would love to clarify a little bit about what you said because it was a lot and it could feel a little overwhelming. What I’m hearing is that one of the tests that doctors may use to diagnose AD is an IgE blood test. And an IgE blood test looks at if you have IgE antibodies. If you have elevated numbers of IgE antibodies, you actually may be allergic to something, which means that you’ll release histamine. And it’s this histamine that might result in an eczema flare. But these blood tests can be a little bit confusing because if you have eczema, it can cause the blood tests to have higher IgE readings. The machines get confused when they process your blood. And if a doctor who’s not specialized in looking at these tests sees this result, they might falsely diagnose you with a food allergy. And that’s why it’s really important to get a specialist to help you interpret these tests and for you to not do it on your own, because it’s very nuanced and it’s not as simple as just seeing the numbers and knowing what’s going on. Did I get that right?
Dr. Gupta: Yes, Kortney! You always say it better than I do. That was perfect. One thing that I want to quickly mention while we are on this topic is that usually for babies, environmental triggers like pollen don’t play a factor until they have had exposure for some time – usually we say around two years. But we have found that dogs and cats, however, can make a difference for babies – and even dust mites, because these are constant exposures. And if the babies are allergic, they can have symptoms of eczema related to that allergy, maybe earlier on.
Also, as you get older, food allergy symptoms in particular won’t simply be eczema because the body generally shows multiple signs of food allergy. So eczema caused only by food allergy is unlikely as you get older. Food allergies are a complicated topic. So I don’t want to go too far into this since our main focus today is on atopic dermatitis. But I just wanted to mention this important point as it relates to atopic dermatitis.
Kortney: Yes, definitely, because it sounds like, as an allergist, you approach diagnosing atopic dermatitis from different angles, as well as depending on the age of the patient. So back to testing. What are other types of tests that you may perform?
Dr. Gupta: So along with IgE testing, especially when we’re concerned with foods, we also usually use a skin prick test. Some physicians might do the skin prick testing before they send you for IgE testing, and some might do IgE testing before skin prick testing. But usually if either test results in a positive test for foods, we use the other to confirm the diagnosis. IgE tests are also good for food allergies to follow the numbers over time. So over time, for example, with egg and milk, if you’re growing out of your food allergen, then those numbers should decrease. So skin prick testing is done for food and environmental allergens, and we use serums containing the suspected allergens. And that serum is placed on the skin and literally pricked into the top layer of the skin with a device that we use, which is a very small needle that can’t get deeper than just under the skin surface. We can test on the forearm or upper back, and then we wait for 15 to 20 minutes, and after that time, we will see raised bumps. And these are kind of like mosquito bites, which strongly indicate an allergy to that particular allergen.
So for this test, make sure that you have to be off of antihistamine medications for at least 3-5 days. And every allergy has a different threshold for the number of days. So before you go in for your appointment, you should definitely check in with the office and find out how many days they want to make sure that you’re off of antihistamines. And then for environmental triggers, we don’t usually do both the skin prick testing and the serum IgE testing. We just stick to one or the other. And the preference for which to choose is really something that we call Shared Decision-Making, which means that we’ll talk to the patient and figure out what makes more sense for the patient. Some can’t come off of their antihistamines for skin prick testing, so they opt for the blood test, where it doesn’t matter what medication you’re on.
Kortney: We have food allergies and we have environmental allergens, and those are done by IgE and by skin prick tests. What about things like soaps and cosmetics? That’s got to be the patch testing, right?
Dr. Gupta: Yes, that’s right. So patch testing is used to determine if chemicals or metals are potential triggers. So we place different chemicals and metals on adhesive strips that are placed on the patient’s back. It is a cumbersome process because you have to go into the office several times and you can’t get your back wet or sweaty during this entire process. So I don’t usually recommend doing this test in the middle of summer when it’s really hot and sticky. That would not be a good time for patch testing. We read the testing after 48 hours and then again after 72 hours, and some also do it again after 96 hours. You have to go to the office. For each of these visits, we look for a reaction to each chemical on the back, and we’ll see things like a small red bump, redness itching, and irritation in the place where the chemical was placed.
Kortney: I know that I desperately need to get this done for some metals and other things, but just itching for two days sounds like a nightmare. Quick question. That’s also something where patients need to not be taking antihistamines at that time?
Dr. Gupta: Good question. So actually, antihistamines don’t really affect patch testing like they do with skin prick testing, but some physicians might prefer you to be off of antihistamines before they patch test you. So I would just check with your doctor. But the important thing is that you can’t be on oral steroids. And the oral steroid cut-off point also varies from position to position, but it’s usually at least one week off of oral steroids. Some prefer two, some prefer three, some prefer four weeks off. And it’s only because these medications can alter the response that your body has, and therefore you might get what we call false negatives, where the skin just isn’t as reactive and so we might miss some of the things that you’re allergic to.
Kortney: Interesting to know. Now, we’ve talked about things that will tell us what’s triggering our AD, but what about any other tests that might rule something out? Is that something that doctors would look at?
Dr. Gupta: So in patients where the diagnosis is difficult, we can also use a skin biopsy. This is where a tiny piece of the skin is removed in the area that is affected, and it’s analyzed under a microscope. This can rule out other skin diseases such as cancer or psoriasis, and can also confirm the diagnosis of eczema.
Kortney: Great. Have we talked all about the tests that you might be using for AD?
Dr. Gupta: Yes, I think that hits on the most important ones that doctors usually turn to.
Kortney: I know that another part of diagnosing atopic dermatitis is about your history – what the patient can tell the doctor about their experience. I know personally, I like to be as prepared as possible when I go to the doctor, because even if I’ve rehearsed what I need to say a million times, I might get there and totally forget because I might get sidetracked or something else might happen. So if a parent or guardian or an adult with AD wanted to bring some information with them to the doctor’s appointment, what should they be writing down to help them help you diagnose their AD?
Dr. Gupta: Yes, I think writing things down is a great tool for all patients for any condition that you have. And it’s really important just because we’re all so busy and jotting down different things that are important when you think of them can help you when you ultimately do see a doctor. And I think at the end of the day, the important thing to remember when diagnosing atopic dermatitis, as I mentioned earlier, is that it’s really a combination of compiling a bunch of evidence together. So it’s the test results. It’s your personal and family history of medical conditions. It’s the physical exam. It’s your home and work environments and what you’re exposed to. And it’s these other activities that might expose you to allergies.
So to reach a diagnosis, it takes all of these factors that we take together to really come to the right diagnosis. And in patients with skin of color who may have a longer time in reaching their diagnosis, I think it’s important to see a specialist if you’re worried that you may not have the right diagnosis or the right treatment. So we really want to help prevent the complications that we see more often in these populations by getting treated and diagnosed as early as possible.
Kortney: Thank you. I feel like that was a really good overview of tests and of what we should know when we think we might have AD. So now what? Well, we’ll be covering that in our next episode, which will be part three of this series. We’re talking all about how you treat atopic dermatitis. Until then, check out part one. If you haven’t, and for more information, you can check out our show notes. For some great resources, you can go to Allergy & Asthma Network’s website or check out EczemaInSkinofColor.org for those pictures that Dr. G mentioned at the top of the episode. And for more really great details on how you can help yourself if you have atopic dermatitis, we’d appreciate a review or a social share to help us get the word out there and raise more awareness around atopic dermatitis and skin of color. As always, thank you for listening.
Dr. Gupta: Thank you for listening to today’s episode. Remember that all information you hear today is for informational purposes only and are not intended to serve as a substitute for the consultation, diagnosis, and/or medical treatment of a qualified physician or healthcare provider.
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