Wet wipes have been accused of a lot of things – creating ‘fatbergs’ in sewage systems, adding to the microplastic threat to marine life, preventing the breakdown of solid matter in landfill sites and causing skin rashes both on the bottoms of the babies on which they are used and on the hands of the parents using them. And now they are being accused of triggering food allergy!
An article in Saturday’s Telegraph linked the use of wet wipes to the development of food allergy. The theory is that the chemicals found in wet wipes may heighten the risk of an atopic baby (one who is already genetically disposed to have an allergy) becoming sensitised to food allergens that it may it may encounter on the skin – a sibling or a parent with peanut butter on their hands transferring that to the baby. While this is possibly stretching the demonisation of wet wipes a bit far, the research which gave rise to the story raises much more serious questions over allergen sensitisation via the skin.
The study which triggered the article appeared in the Journal of Allergy and Clinical Immunology last month. It showed that if you skin sensitise neonatal mice with food allergens, and then you challenge them orally with those allergens (e.g. you made them eat them) they will have an allergic, and possibly an anaphylactic reaction to that food.
Despite the Telegraph‘s headlines, this is not ‘new’ news. There have been a number of studies showing that where the skin barrier is damaged, allergens (such as peanut oils) can penetrate and sensitise the immune system so that when it next encounters that allergen (in a food) it reacts to it. If, on the other hand, the immune system first encounters the allergic protein via the gut (when it is eaten) it does not see it as harmful and does not react. This was clearly demonstrated in the LEAP study in 2015 which showed that if you fed peanut proteins to at-risk infants from a very young age you dramatically reduced the risk of them developing peanut allergy later.
However, this study raises, a far more worrying issue both as far as allergic patients and the allergists treating them are concerned. If it is not only possible but easy to sensitise an atopic person, be they adult or child, to an allergen via the skin, could the skin prick tests, which are designed to diagnose allergy by deliberately introducing an allergen through the skin, not actually induce that allergy?
That is exactly what worries – and has worried – Dr Janice Joneja (Dr Joneja of our Beginners and Comprehensives Guides to Histamine Intolerance) for some years. She has never used skin prick testing in her own practice and is deeply concerned that her colleagues continue to do so. And do so despite:
- Mounting evidence of allergy sensitisation through the skin
- The fact skin prick testing itself has never been tested for safety – and
- The fact that skin prick testing is widely recognised to be extremely unreliable producing a large number of false positives (‘diagnosing’ an allergy which does not exist) and false negatives (failing to diagnose an allergy which does exist) – and that there are other tests available which use blood drawn from the body rather than injecting allergens into it.
As she says:
‘There are no published research studies to prove either the danger or the safety of skin testing. Any invasive technique requires extensive research before it is approved for use….. No such studies have been carried out on skin testing, although thousands of such tests are performed every day in medical offices and clinics throughout the world. Because the techniques of skin testing – prick, scratch, intradermal and patch delivery of the allergen – have been employed for decades, little thought has been given to the immunological processes involved in the tests although immunological responses clearly occur witnessed by the wheal and flare reaction.
An immunological response is not trivial….. indeed it is the process involved in vaccination. Vaccines are delivered by injection, and more recently via skin patch – similar to the techniques used in skin testing. But while no vaccine is approved for use without extensive testing on both animals and humans, skin testing has never been tested for safety on either humans or animals.’
For Dr Joneja’s article on the subject see here on the Foods Matter site.
So where does this leave parents of atopic infants? As one of our readers, the mother of two children with multiple and severe food allergies, says:
‘Our sons have been undergoing these skin prick tests since they were toddlers and, as with many children with allergies, very often their first contact with a particular food allergen was through the skin for these diagnostic tests. For example, our eldest son had never knowingly eaten any type of nut or seed before a skin prick test revealed him to have severe allergies to peanuts, hazelnuts, cashew nuts, pistachio nuts, brazil nuts and sesame seeds.
He is a highly allergic child, so he might well have developed allergies to these foods had he first been exposed to them as a food. However this mouse research suggests that eating an allergen before being exposed to it via the skin makes it much less likely that someone will react. So I am left wondering about the safety of all the skin-prick testing he underwent and whether some of his allergies were actually triggered by the tests themselves.’
17th May 2018
Dr Adam Fox is consultant paediatric allergist at a leading London children’s hospital. He is President Elect of the British Society of Allergy & Clinical Immunology and chairs their Paediatric committee. He is also trustee and Chair of the Advisory Board of Allergy UK, and member of the Anaphylaxis Campaign Clinical and Scientific Panel.
In response to Dr Joneja’s article he says:
‘Skin prick testing is internationally accepted as a safe method of allergy testing and is endorsed by organisations around the world as part of standard allergy practice eg NICE, European and American Allergy academies. Whilst there has been longstanding interest in the role of skin exposure to allergens as a way of developing sensitisation, this is quite distinct from skin prick testing and there is no published evidence at all to suggest that skin prick testing in anyway contributes to the development of allergies.’
I don’t know what to say.
So if you stop using wipes and allows development of the skin barrier, will it allow allergies to go away?
I’d say that skin tests are only so-so in reliability. Sniff tests, where one sniffs a small amount of pollen or some other allergen, are probably more accurate, although seldom done any more.
I’d also say that from what I’ve seen, blood tests for allergies may be even less reliable than any of the other tests.
That skin testing itself can lead to allergies is very interesting…something to explore further.
It is more about preventing the allergies developing, Amit. The suggestion is that using soap and water and washing the soap away thoroughly will help to prevent the allergens penetrating the skin and sensitising the person concerned. Once that person is sensitised, using or not using wipes will not make any difference.
Indeed this is not news. I wrote about thinny skinny problems for you first in 2009! Blimey, that was a while ago, but still one of my popular articles, happily.
This is so insulting to parents everywhere–to say that wet wipes can cause food allergy, or eczema, and then to go on using the skin prick test. I noticed my child was adding new food allergies, to foods she had never, ever been exposed to, except through the skin prick test. Not only that, the skin prick test causes a flood of histamine in the body, which is pretty much what atopic people are supposed to be avoiding (histamine overload). So, I researched and researched and researched everything to do with the immune system–I asked biochem friends, “Could this develop allergies?” One of my friends who is a brilliant biochemist said, “Of course, every scientist knows that blood + antigen = antibody.” You have children who are already genetically prone to allergy and then you are setting them to develop allergies in this way–in the allergist’s office. I questioned the allergist on the skin prick test at the local Children’s hospital and I was told by this ancient male that I was crazy! Seriously, we are still doing this to mothers–mothers who have spent hours and hours connecting the dots researching and backing up with they observed in their children with science are told they are crazy! Finding Dr. Joneja was a miracle to me, and sadly, I feel she has experienced the same sexism in the medical world. Moms: trust yourselves. At the very least realize all those terrible hives are flooding your poor child’s system with histamine, which is what you want to avoid. Thank you for this great blog post.
Sadly, your experience with allergist at the skin hospital is all too common – as so many allergy sufferers will attest. Dr Joneja is good at treading her own path – her medical colleagues’ refusal to accept that there could be a problem with skin prick tests is only equalled by their refusal to accept that histamine excess could itself be a problem.
Indeed you did, Micki – and this weekend’s newsletter will not only carry Dr Janice’s article but your Skinny Thinnies and several other ‘goodies’ from our archives both about barrier and about allergy testing/diagnosis.
A reader in Canada commented:
‘So you mean the actual tests the allergist does? That makes sense, my daughter had eaten chocolate before and had no reaction. After they tested her ( the test ended up being negative) she had a terrible reaction to “enjoy life” chocolate chips. She actually started vomiting the minute they entered her mouth.’
This potentially could be the cause of the of severe food allergies and perhaps should not be used on children until proven safe perhaps by medical trials of volunteer adults ? I did have prick tests when I developed asthma as a young adult but as far as I remember none of the tests were for food. I have developed allergic reaction to penicillin since then and was told by a doctor the reason I develped this allergy was because I had penicillin too often. I also developed hayfever later. One of the allergies is birch pollen and as have severe sensitivity to aspirin have been warned can become allergic to a couple of foods because of this. It must be very alarming thought to a parent that prick tests may cause a life threatening allergy.
Another comment from Canada:
“My DD was being being treated and followed by our ND since birth on her food sensitivities with no adverse reactions. We kept ahead of her sensitivities and avoided the foods we were made aware of. Our new MD decided to send her for the scratch test in which they pricked her with 30 foods, many of them known sensitivities.
No reactions to the scratch test right away but Starting that night and for 2 full weeks after, she had loose bowels so severe she was having BM every single night in her sleep. She was 5.5 yrs old and had NEVER had BM overnight since infancy. No other symptoms. No fever, no malaise, no vomiting. I reported to the allergist and MD and both of them brushed me off saying it’s an unusual reaction. I said I don’t care if it’s unusual, it was her reaction so write it down. Never went back to either of them.
Found a much more well rounded, educated MD. Had to go back to ND for immune support since DD’s system was going haywire. We had to re-eliminate some of the foods she was originally cleared to eat prior to the scratch test. Probably put us back about 6 months”
A further comment just emailed to us:
If the research reported can be shown to be conclusive, is it safe to first encounter foods through our skin membrane rather than orally, as we would if we were eating them? Do we yet understand enough about any risks of pushing food extracts through the skin of children who (due to their attendance at a food allergy clinic) are already at high risk of developing allergies?
I understand that skin-prick tests are a quick and cost-effective way of identifying possible allergic sensitivity but it seems to me, given this new study, that further research may be required to assess whether they may actually have the potential to induce allergic sensitivity to certain foods.