Feature Image — Allergic March or Atopic March [Ref 1]
The feature image shows the relationship of four allergic diseases. The order of their appearance give them the title of the Allergic March or Atopic March. There is a defined order of appearance of the four diseases. Atopic dermatitis (AD), also called eczema, generally develops first, in infancy, and in many, this is followed by immunoglobulin E(IgE)-mediated food allergy (FA). Allergic asthma (AA) is the next to appear, and finally allergic rhinitis (AR).
1-Atopic dermatitis (AD) or eczema
Atopic dermatitis develops in 17-24% of children. The prevalence of symptoms peaks by two years of age. Happily, about half of the children with AD go into remission by adolescence, while AD persists into adulthood in the remaining half. [1]
2-Food allergy (FA)
The risk of FA onset is six times higher in children with AD compared with those without AD. The prevalence of FA peaks at about 10% at 1 year of age, and specific IgEs for food allergens are detectable in infants at 1 month of age. [1]
3-Allergic asthma (AA)
The two early allergic diseases are often followed by asthma and hay fever. Studies have shown that two-thirds of patients with eczema develop hay fever and one-third develop asthma. Not all children follow the trend of eczema to food allergies to asthma and hay fever. There are variations. Many children outgrow their allergies and asthma; some develop asthma and allergies for the first time in adulthood. [1]
4-Allergic rhinitis (AR)
The risk of asthma and allergic rhinitis unlike atopic dermatitis and food allergy are sensitised to inhalent allergens and mostly occurs after infancy. Its annual incidence and prevalence increase markedly after 3 years of age. The sensitivity to inhaled allergens provides a possible explanation for the late development of AA and AR in the atopic march.[1]
Among children with AA, 74-81% have AR [1]. AA was reportedly more severe and harder to control in children with both AA and AR, and AA was better controlled when AR was treated. Appropriate management of AR not only improves the symptoms of AA, but also improves airway hyper-responsiveness. According to these findings, AA and AR are considered to be “one airway, one disease”. [1]
The causes and symptoms of AR are shown in Figure 2 below.
Take home messages
A good understanding of the four allergic diseases both in the risk factors, identification, and treatment will go a long way to reduce the burden of these diseases. Avoidance of risk factors where feasible is important.
Acknowledgments
Grateful thanks are due to the following authors for the reproduction of graphics and pictures from their publications
1-Dr Vanitha Sampath for the feature image on Allergic March. See Reference 2.
2-Drs Jain BS et al for Figure 2 on the inhalled allergens and symptoms of allergic rhinitis. .
References
1-Tsuge M, Ikeda M, Matsumoto N, Yorifuji T, and Tsukahara H. Current Insights into Atopic March. Children. 2021. 8:1067. https://doi.org/10.3390/children8111067
2-Sampath V. The Allergy-Asthma Connection. Sean N Parker Center for Allergy & Asthma Research. Stanford Medicine. Feb 2016. doi:https//med.stanford.edu/allergyandasthma/news-from-our-center/allergy-asthma-connection.html
Dr LG Goh
Dr GOH Lee Gan is a retired Associate Professor in the Department of Family Medicine, National University Health System. He has an interest in learning and teaching how we can age well everyday (AWE).
