Allergic Contact Dermatitis in Children (I) – Q&A with Dr Steve Xu

Eczema is a skin condition with many parts to the puzzle – it is linked to hereditary skin condition, allergens (food, inhaled, contact and airborne), environmental factors (heat, humidity), bacteria colonization on skin (and how gut microbiome may affect allergic conditions), lifestyle factors (stress, hormonal change) and also suspected to be linked with diet/ water. Very often we may think of what we have eaten, rather than what we have applied on our skin. A moisturizer or topical prescription tend not to fall under our usual ‘list of suspects’ when we try to figure out what’s triggering the eczema.

This 2-part blog series aim to bring greater awareness of contact allergens, and how some of these may be the ingredients in your skincare products. Especially for pediatric patients, we have to be even more careful because:

  1. Babies’ skin barrier is thinner than that of an adult- making it extra vulnerable to chemical irritants (also greater transepidermal water loss and therefore, moisturizing is important)
  2. Increasing research showing that a strong skin barrier has protective effect against eczema, and reduce likelihood of food sensitization
  3. Babies have a larger surface area to volume ratio, therefore potentially the risk associated with chemical absorption is higher
Contact allergens is of particular importance to pediatric patients

Contact allergens is of particular importance to pediatric patients

I’m privileged to have dermatologist Steve Xu, MD MSc to help with this series. Dr Steve is currently a 2nd year dermatology resident at McGaw Medical Center of Northwestern University. He earned his MD from Harvard as a Soros Fellow, and a Masters in Health Policy and Finance from The London School of Economics as a Marshall Scholar. He completed a BS in bioengineering at Rice University. For his academic interests, Steve is focused on consumer education and the intersection between health policy and clinical medicine. His publications have appeared in The New England Journal of Medicine, and PLOS Medicine garnering broad press attention from sources such as CNN, The Washington Post, and The Los Angeles Times. Dr Steve has created a web resource for patients with eczema and contact dermatitis at itchyrash.org. See also Dr Steve’s publications at the end of this post.

Dermatologist Dr Steve Xu MD

Dr Steve Xu MD, MSc

Allergic Contact Dermatitis – What is it?

MarcieMom: Contact dermatitis refer to skin rash that is triggered by contact with an allergen/ irritant. If the immune response is that related to IgE, it would be allergic contact dermatitis; conversely, if the response is due to overtime exposure to the irritant (leading the skin to develop delayed-type hypersensitivity), it is irritant contact dermatitis. 

The thing is a child can have all the different types of dermatitis – atopic, allergic contact and irritant contact.

MarcieMom: Dr Steve, thank you for joining me for this series. The different terms can get very confusing for parents of eczema children. How would you explain the different types of dermatitis to a patient?

Dr Steve Xu:  Right now even within the scientific community, there’s a big debate on what exactly we should call ‘eczema’. At our institution (Northwestern University), this is how we break it down.

The term ‘eczema’ itself actually describes how a certain rash looks.  Atopic dermatitis, allergic contact dermatitis, and irritant contact dermatitis all can cause an ‘eczema’ rash that looks exactly the same. Eczema used as a standalone term isn’t really specific.

For classic childhood ‘eczema’, we refer to this as atopic dermatitis. Allergic and irritant contact dermatitis is defined as a condition where an external agent leads to an eczematous rash. We define the difference between allergic and contact dermatitis here. Basically, an allergic contact dermatitis is defined by an immune-mediated response to an external agent applied to the skin. These reactions typically require only a very small amount of the agent to lead to a rash. Irritant contact dermatitis is not immune related but leads to an indistinguishable eczematous reaction. Typically, more of an external agent must be applied to cause a rash in irritant contact dermatitis.

MarcieMom: In practical terms, is diagnosing the type of dermatitis important? Or knowing the triggers are adequate for management of eczema?

Dr Steve Xu: Yes, definitely. An irritant contact dermatitis usually requires more of the external agent to cause a rash. This is practically important because if you only have an irritant contact dermatitis you may be able to tolerate products that are wash off or rinse off. If you have an allergic contact dermatitis, then we recommend avoidance altogether. Even a little exposure can cause a miserable rash.

Prevalence of Allergic Contact Dermatitis

There is increasing evidence that allergic contact dermatitis is underreported in children and while traditionally thought as unlikely for children, contact dermatitis is becoming more common.

MarcieMom: In the article1, the top ten pediatric allergens found in personal hygiene products are listed (with the first as having most percentage of children being hypersensitive to it):

  1. Neomycin – topical antibiotic, another contact allergen is over-the-counter antibiotic Bacitracin
  2. Balsam of Peru – also known as Myroxylon pereirae, chemically related to fragrance and thus used to screen for fragrance allergy
  3. Fragrance mix – Of the flowering plants, the Comositae family is the most likely to cause skin sensitization, such as chamomile, dandelion and ragweed; also cross-reactive with propolis (beeswax)
  4. Benzalkonium chloride – ammonium compound used as preservative, including in disinfecting wipes and eye drops
  5. Lanolin – natural oil from sebum of wool-bearing animals
  6. Cocamidopropyl betaine (CAPB) – used as a surfactant
  7. Formaldehyde – preservative, also associated with quaternium 15, imidazolindinyl urea (most common), diazolidinyl urea, bronopol, dimethyl-dimethyl hydantoin (this can get very tricky to memorize, readers can refer to this table created by dermapathologist in a previous interview)
  8. Methylchlorsothiazolinone (MCI)/ Methylisothiazolinone (MI) – likely to be in bubble baths, soaps, cosmetic products, and baby wipes
  9. Propylene glycol – previously common in moisturizers (but many brands stopped including propylene glycol: it has humectant properties and also an emulsifier) and topical steroids
  10. Corticosteroids – when using steroid creams, we have to be aware of its potency, but we may now have to know its likelihood of being contact allergen (we will discuss this next week)
Top 10 Pediatric Contact Allergens in Personal Hygiene Products

Top 10 Pediatric Contact Allergens in Personal Hygiene Products

Other than the above 10, the other well-known contact allergens are cetylstearyl alcohol, sodium lauryl sulphate, pehnoxyethanol, parabens, TEA (triethanolamine) and vitamin E.

Nickel and cobalt are also common contact allergens but less likely that children will come into contact with them.

MarcieMom: It is interesting to note that the above can be found in personal care products, even in those marketed for children. I’m wondering if there is an increase in sensitization in personal hygiene/ skincare products? If so, why? (for instance, is it the increased use of products? Or increased awareness/ patch testing/ consultation)

Dr Steve Xu: The prevalence of contact dermatitis has remained stable overall but certain chemicals are representing a larger share of problems. This is related to industry trends. For example, as formaldehyde was phased out over the past 20 years in personal care products, we’ve seen a growing use of methylisothiazolinone as a preservative. It’s unsurprising that methylisothiazolinone contact allergy is rising rapidly.

Pediatric dermatologists have really worked hard to raise awareness among pediatricians and allergists about contact dermatitis in kids with atopic dermatitis. More than half of kids with atopic dermatitis will have a relevant positive patch test. In general, we’re arguing that kids with atopic dermatitis should be patch tested more and tested for food allergies less

Parents need to know that just because a product is labeled “For babies” or “Safe for kids”, it doesn’t mean it’s any different than what products are sold for adults. These are just marketing claims. Statements like “sensitive skin safe” ororganicalso aren’t regulated. Even carefully reading the labels may not be completely fool-proof. Often times, manufacturers do not have to be specific about which fragrance they are using (different fragrances can cause contact dermatitis).

MarcieMom: Practically, this feels like being caught between a rock and a hard place. The baby’s skin loses more moisture, has less lipids and for babies with dry skin, even more so we have to moisturize. Now, we know the common contact allergens to avoid and of course, should take the effort to read the product label and make sure we’re not putting something on our babies with these allergens. YET, the more we put something on our babies, the more likely the skin can become sensitized to it overtime! (for instance, lanolin, CAPB weren’t previously contact allergens)

MarcieMom: Is there a strategy to moisturizing to reduce likelihood of contact dermatitis? For instance, rotating skincare products which one expert has previously mentioned.

Dr Steve Xu: We often have patients come into our clinic with classic allergic contact dermatitis and exclaim: “I haven’t changed my products in years!”. In truth, this is exactly how a contact allergy develops. It’s true that small, continued exposures over time train your immune system to develop an allergy.

Interview with dermatologist Dr Steve Xu, MD

Interview with dermatologist Dr Steve Xu, MD

With that being said and to the best of my knowledge, there are no well-designed clinical studies showing that rotating skincare products reduces the risk of future allergic contact dermatitis. I’m hesitant to recommend this strategy.

Here’s some practical advice to perhaps help answer this question. Let’s say you have a child with atopic dermatitis and it’s fairly well controlled. Over the course of a period of time, let’s say the atopic dermatitis has taken a turn for the worst and is not getting better with optimal therapy. Or, let’s say that that the atopic dermatitis is appearing in areas it never has before (e.g. belly button, waistband, wrist). Then, this is a time to consider whether there is a simultaneous allergic or irritant contact dermatitis. Patch testing would be recommended.

If there is a relevant positive patch test, than this is the time to follow a safe list. Severely limiting what skincare products or household products can be used in the absence of a patch-test proven allergen may be overkill.

MarcieMom: Thank you Dr Steve for helping us to understand more about contact dermatitis; for me, I’ve learnt that there is practical benefit of knowing the type of dermatitis one is suffering from, and being mindful of the possible development of contact dermatitis for an eczema child. Look forward to next week where we will discuss more about skincare product, prevalence of contact dermatitis in kids and corticosteroids.

References:

  1. Hannah Hill, Alina Goldenberg, Linda Golkar, Kristyn Beck, Judith Williams & Sharon E. Jacob (2016): Pre-Emptive Avoidance Strategy (P.E.A.S.) – addressing allergic contact dermatitis in pediatric populations, Expert Review of Clinical Immunology, DOI: 10.1586/1744666X.2016.1142373

For some of Dr Steve’s publications, see below:

  1. Xu S, Walter JR and Bhatia A. Online Reported User Satisfaction with Laser and Light Treatments: Need for Caution. Dermatologic Surgery. Published online September 9th, 2016. DOI: 10.1097/DSS.0000000000000862.
  2. Xu S, Kwa M, Agarwal A, Rademaker A, and Kundu RV. Sunscreen Product Performance and Other Determinants of Consumer Preference. JAMA Dermatology. 2016. 152(8):920-927.
  3. Walter JR and Xu S. Therapeutic Transdermal Drug Innovation from 2000-2014: Current Status and Future Outlook. 2015. Drug Discovery Today. 2015. 20(11):1293-1299.
  4. Walter JR and Xu S. Topical Drug Innovation from 2000 through 2014. JAMA Dermatology. 2015. 151(7):792-794.
  5. Xu S, Heller M, Wu PA and Nambudiri VE. Chemical Burn Caused by Topical Application of Garlic Under Occlusion. Dermatology Online Journal. 2014. 20(1). URL: https://escholarship.org/uc/item/88v527wg.

Science of Skincare Products – Eczema Supportive Care

Elisabeth Briand Interview on Science of Skincare ProductsThis is a 4-part series focused on understanding the science behind skincare products so that parents of eczema children and eczema sufferers can better understand what goes into the bottle. For this series, I have Dr. Elisabeth Briand, R&D manager at Skintifique. Elisabeth holds an Engineering Master’s degree in food industry and a PhD in chemistry. Before working for Skintifique, she had 10 years experience in academic research as a physico-chemist, in France at Paris VI and Paris XI faculty of Pharmacy and in Sweden, at Chalmers University of Technology. In this interview, Dr. Elisabeth is helping us to understand the science of laboratory-tested skincare products.

MarcieMom: Thank you Elisabeth for joining me again for this last part of our skincare products. Ive covered in this blog that moisturizer has preventive effect on eczema and for those with eczema, moisturizing frequently is able to reduce the use of corticosteroid cream. What I would like to focus in this interview is whether the type of cream, how we apply and when we apply will make a difference in the functions of the moisturizer.

MarcieMom: We are aware that the more liquid a moisturizer is, the shorter time it will last but it is more comfortable to apply than an ointment (which has little to no water content), especially in hot and humid weather like Singapore or during summer. Does the nature of whether it is lotion, cream or ointment affects the efficacy of the skincare product? For instance, does being lotion meant it is more easily absorbed and being ointment meant it will be longer-lasting?

Dr Elisabeth: Many kinds of products are indeed available to help and promote skin health. The same principles as those described earlier work for all of them: products with few ingredients and safe ones will be better for sensitive and fragile skins.

Various kinds of products will, as you said, give different kind of feel and the aim may (or may not) be different as well. The purpose of the two products is different, while ointment is often used to bring a lot of fatty acids the skin and add an occlusive layer to reduce the TEWL (Transepidermal Water Loss or water that is lost through the skin), cream is more used to bring water to the epidermis, as well as other hydrophilic compounds that could be of interest. Creams bring also hydrophobic compounds (fatty acids, hydrophobic active ingredients, …) but to a lesser extent.

The long-term efficiency of a product will depend on how it is structured and how quickly the compounds are delivered to the skin and absorbed. For ointment, they generally have an occlusive layer that will remains on top of the skin, which is the purpose of these ingredients so that it can prevent water to evaporate from skin. So the feel it gives and that specific function will last for a rather long time. On the contrary, water and active compounds are delivered quickly and evaporate or absorbed quickly by skin. As a consequence, the moisturizing feel disappears rather quickly

One of the achievements that may be reached by using innovative structure is to make cream that have a feel comparable to a classical cream, but will display a long-lasting delivery of the active ingredients, and then combined some of the advantages from an ointment (long-lasting relief and effect) and from a classical cream (pleasant feel, bringing water to the skin).

Skincare Moisturizer as Eczema Support

MarcieMom: The other bigquestion that all parents have is each skincare company claims that their product is able to hydrate, build the skin structure better. These typically belong to the group of moisturizers that contain ceramides or have the ability to restore the skin lipids. In your view Elisabeth, is there certain characteristic (such as ingredients or process) that will differentiate a category of moisturizer as being better at restoring skin functions than others?

Dr Elisabeth: Efficiency is claimed by all companies, of course, because all products will bring the element that will help skin moisturizing, at least in the short term. It is clear however that some products will be more efficient than others; just like some products will have better feel than others etc. As mentioned in our previous discussion, this is why scientific innovation and knowhow comes into play: in our view, they are the key to make better, more efficient and safer products

Ceramides are indeed one of the components that enter in the composition of skin membranes and seems to play a role in its restoration. There are however several types of ceramides and all of them do not seem to display the same efficiency according to various recent publications. What will help skin to be restored is to protect it from threats, and nourish it with proper ingredients. A general appellation of Natural Moisturizing Factor has been created to describe these ingredients that can play a positive role in skin restoration. Ceramides are only one of them. For example, vegetal oils are mainly made of fatty acids that interact with skin cell membrane and help it to be “nourished”. Some of these oils also have additional compounds that will play a positive role. Glycerin, urea, aminoacids, cholesterol, and many other ingredients can play a role in restoring skin functions. What is important is to determine which ingredients will be helpful in a specific situation, and how you can maximize the efficiency of this ingredient in the molecular structure that you create inside the product.

MarcieMom: Readers of this blog are familiar with basic skincare, such as moisturizing right after shower and making sure to moisturize enough. Either due to cost or belief of effectiveness of certain way of moisturizing, some parents may

  • apply brand A moisturizer in the day, and brand B at night; or
  • apply brand A on certain days of the week and brand B on others (or alternate by weeks);
  • apply brand A (a lotion) and brand B (an ointment) over it.

In your view, which is the skincare moisturizing method that make sense? For instance, with constraints that many families have, such as budget and time to moisturize (e.g. child in school or simply to reduce the number of times moisturizing is needed).

Dr ElisabethA daily moisturizing routine is indeed driven by various factors, lifestyle included. A product can be efficient, but if it is a hassle to use it, it won’t be used properly and will become inefficient. I would say there is no “you have to” routine, just find one that is working for you. If you keep in mind the principles I already described: using efficient products with few and safe ingredients, you can find what works the best for you. And it may be completely different from what works for another person. And it can be the same product or products for a very long period of time. Regularly changing skincare products from time to time can be a good idea when you are using products that contain a lot of ingredients. or that contain an ingredient you are slightly sensitized to. So you will give a rest to your skin that would otherwise be exposed to some ingredients that could become unhealthy with time and regular use.

MarcieMom: Many eczema sufferers feel that rotating the emollient seems to make it more effective than always using the same emollient. Is there some basis for that?

Dr ElisabethThe efficiency of a product is determined by its ability to bring what is needed by the skin to be protected to help restore its functions. Rotating products can be a way to bring various efficient ingredients that are not found in only one products. But as I just mentioned before, there can be other reasons that can make an emollient less efficient, so you have to switch from it for a while. Some ingredients can lead to some sensitization of the skin. Not strong enough to give a rash, but strong enough to lead to some irritation if used over long periods of time, that would explain why a product would become less efficient. Reducing the number of ingredients can decrease this risk and in that case, your emollient will work for a longer time.

Thank you Elisabeth of being ever so patient in this series of interviews on skincare products, tackling specifically the science behind it. It is truly enlightening and practical!

For all interviews under this Science of Skincare Products series:

Science in the Bottle

Safety and Product Expiry Date

Stability

p.s. Declaration of no self-interest – is that what it’s called? lol Just want to let you know that Dr Elisabeth left a comment on my blog and I felt she was very helpful. When I realized her area of expertise, I suggested that we collaborate on a ‘science-y’ series as I’ve always been intrigued by it. No money has changed hands, only time invested to bring this series to you all!

Sensitive Skin Product Series – Understanding Hypoallergenic

Testing Hypoallergenic (picture from vmvhypoallergenics.com)

This is a 13-part series focused on understanding and using products for sensitive skin, an important topic given the generous amount of moisturizers that go onto the skin of a child with eczema. Marcie Mom met Laura Verallo Rowell Bertotto, the CEO of VMVGroup, on twitter and learnt that her company is the only hypoallergenic brand that validates its hypoallergenicity. VMV Hypoallergenics is founded in 1979 by Dr. Vermén Verallo-Rowell who is a world renowned dermatologist. Dr. Vermén created the VH Rating System which is the only validated hypoallergenic rating system in the world and is used across all the products at VMV. In this interview, Laura answers Marcie Mom’s questions on understanding the product label.

Terms on Product Label – “Hypoallergenic”, “Natural”, “100% Organic” – What They Really Mean and Do They Mean Well?

Common terms that the average consumer may look out for will be ‘hypoallergenic’, ‘natural’ and ‘100% organic’. Hypoallergenic refers to less likely to cause allergies while the definition of ‘natural’ and ‘organic’ is vague.

Marcie Mom: Laura, thanks for helping to answer these questions that confuse me and so many parents looking for a suitable moisturizer for their eczema child. Let’s tackle them one by one.

Hypoallergenic – I’m looking at my baby’s moisturizers and one brand says hypoallergenic while the other does not. I read that at VMV, you rate a product using the VH Rating System that grades a product safety based on how many allergens it does not contain (i.e. higher score means less allergens). However, I don’t see such rating system in other brands. How do I then know how hypoallergenic it is? Or in other words, is there a regulatory body that ensures the product meet at least some criteria before it can be labeled as ‘hypoallergenic’? And, is some country stricter in the use of the term?

Laura: Actually, the “hypoallergenic” claim is one of the biggest problems with cosmetics — different FDAs regulate the term differently and some don’t at all. Even when there are regulations, these are minimal or are poorly defined. This applies to the United States as well where a judicial ruling in the 1970s for the FDA to regulate the term was overturned by the Court of Appeals. http://www.fda.gov/Cosmetics/CosmeticLabelingLabelClaims/LabelClaimsandExpirationDating/ucm2005203.htm

As a result of this decision many U.S. manufacturers can label and advertise their cosmetics as “hypoallergenic” without being required to provide supporting evidence. Consequently, neither consumers nor doctors have much assurance that such claims are valid. One recent ruling by the US-FDA requires that ingredients used in cosmetics be listed in the product label — which is definitely an improvement but unless one is extremely familiar with ingredient names, it may not be of much help regarding the hypoallergenic claim.

This lack of definite regulatory criteria for the “hypoallergenic” label is a problem for those who really need hypoallergenicity or who want skin-safer care. Dermatologists tend to not respect the claim and consumers, as you mention in your blog, are at a loss about how to interpret it.

VH-Number Rating System

It’s precisely because of this lack of regulation that our founder, a dermatologist-dermatopathologist who specializes in several diseases like chronic and recurring contact dermatitis and atopic dermatoses, created the VH-Number Rating System. She wanted an objective way to prove hypoallergenicity — one whose criteria are clear, reliable, repeatable, easy for the consumer to follow, and whose basis is respectably peer-reviewed and published.

The VH-Number Rating System is based on a list of allergens. This list is collated from the assessment by independent groups from Europe, the United States, Canada and other countries of contact dermatitis experts who regularly do patch tests and publish the ranking of these allergens. Altogether, these doctors now test over 20,000 people yearly. Because the patch tests are done on so many people across many countries, and are updated every few years, this list is the most reliable reference for the top allergens that produce allergic reactions in people.

In our products, we use this list to know what to OMIT from our formulations. And the VH-Rating System is the only system to show how many of these allergens are NOT in a product. It works a little like an SPF in that it’s a simple numerical guide as to the hypoallergenicity of a product. As with an SPF, the higher the VH Number the better (the more allergens are omitted).

This VH system was recently published in Dermatitis, the journal of the American Contact Dermatitis Society and a leading publication on contact and atopic dermatitis. The article states that the VH-Number Rating System is “shown to objectively validate the hypoallergenic cosmetics claim”. So finally, yes, there is a way to objectively measure a product’s hypoallergenicity.

When Products are Not Rated

If a brand does not use the VH-Rating System (it is proprietary to VMV), you have to be a bit of a contact derm AND chemistry expert. Why?

First, you have to have access to or memorize the list of allergens. Right now, there are 76 allergens…quite a lot to memorize. As well, the list changes every few years, so you’d have to keep up-to-date…not easy if you’re not a dermatologist who specializes in this.

As well, you’d need to know your chemistry well enough to be able to recognize the different names that ingredients can sometimes have. For example:

1.   Fragrances are always top allergens…but you may not know that cinnamic alcohol is actually a type of fragrance.

2.   “Preservative-free” product may be using fragrances to preserve the product but unless you recognize the chemical or “INCI” (International Nomenclature of Cosmetic Ingredients) name, you may not realize it.

3.   Cross-Interaction – You may also not know which ingredients cross react with each other. For example, beeswax is an allergen…but propolis is related to it.

4.   Similar Names – More mind-boggling examples are things like SLS and SLES. Neither are on the allergen lists. Both have had some irritations reported (not so much allergic reactions) but far more with SLS and in both cases, reactions seem highly concentration-related. BUT both ingredients actually have the initials SLS…you would have to know that SLS is Sodium LauRYL Sulfate (to avoid) and SLES is Sodium LaurETH Sulfate (relatively ok).

Marcie Mom: Thanks! I’ve certainly learnt lots about what’s hypoallergenic and look forward to learning about the other common terms used in product label!

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