by Swen Malte John, MD, PhD

You don't die of allergic contact dermatitis (ACD). This is a positive information on the one hand. However, on the other hand, that is also the reason why contact dermatitis doesn't find the awareness it would deserve. Many physicians even think that ACD is completely irrelevant, at least in childhood. It is not. Dr Kari Martin has made clear the epidemiological magnitude of the problem with up to 25% of positive reactions to patch tests even in healthy children (with the detected sensitisation being a timebomb, which may lead to a dermatitis any time).  In diseased children with a suspicion of ACD up to 96% of patch tests show positive results.

The spectrum of contact sensitisers is ever-changing and there is a substantial overlap of potential allergens between children and adults. Most recently, in North America and in Europe, the growing number of reported ACD cases to dermal glucose sensors for continuous glucose monitoring, which in 83% can be attributed to isobornyl acrylate, has raised quite some interest in paediatrics. It took a while to identify this new allergen (and further culprit acrylates), due to the fact that the manufacturers so far do not have to declare the ingredients of their medicinal products. With a focus on ACD there should be obligatory declaration of ingredients of every medicinal product. Another new allergen which is particularly prone to children is acetophenone azine which can be found in foam padding used in shin pads, shoes, flip-flops, and which has been shown to penetrate fabrics. Thus, the American Contact Dermatitis Society has announced it as “Allergen of the Year 2021”.

Obviously, the clinical presentation of ACD in children may differ from those in adults and history taking to link dermatitis to certain contacts will frequently be jeopardised in children. The affected body region in many cases may be the only clue-giver; e.g. a rash on the buttocks may well be linked to sanitising agents like for cleaning of toilets or potty-training equipment. ACD on the lips may amongst the obvious (musical instruments, lip balms) also be toys, including slime. It definitely pays to raise awareness to the fact that ACD does happen in children, as the number of potential culprit allergens does rise, with so many more chemicals being produced throughout the world, but also due to changing trends, e.g. as to herbal medicine, not infrequently containing rather strong botanical sensitisers.