Detection and analysis of serum allergens in 5349 children with eczema

Objective To detect common allergens for children with eczema and identify the possible factors that trigger allergy, so as to provide evidence for treatment and prevention of eczema. Methods A total of 5 439 children with eczema who were treated in Department of Dermatology, Shanghai Children's Hospital, Shanghai Jiao Tong University from January 2014 to January 2019 were enrolled. They were divided into three groups according to their ages: group < 1 year old (n=1 674), group 1-3 years old (n=1 818) and group >3 years old (n=1 857). Their levels of serum total IgE were detected by immunoblotting, and the levels of serum specific IgE (sIgE) were quantified. The results were compared among groups at different ages. Results The level of total serum IgE increased in 3 179 children (59.43%), and the positive rate of sIgE was 75.47% (4 037/5 349), where the positive rate of food allergen(65.17%) was higher than that of aeroallergen (42.25%). The common food allergens were milk (47.84%), egg white (36.42%), beef (10.23%) and cashew (7.95%). The common aeroallergens were Dermatophagoides pteronyssinus/Dermatophagoides farinae (DP/DF) (34.68%), house dust (9.52%), cat dandruff (3.59%) and mould combination (Aspergillus fumigatus, etc.) (2.94%). Differences in main allergens were found in eczema children at different age group. For children under 1 year old and aging 1 to 3 years old, their main allergens were milk, egg white and DP/DF. For children over 3 years old, DP/DF, milk and egg white were the main allergens. The difference was statistically significant (P<0.05). Conclusions Milk, egg white and DP/DF are the most common allergens for eczema children, which may result in allergy at a high risk. With the growth of children, aeroallergens gradually become the main allergen instead. Serum sIgE detection can indicate the allergens involved, which is helpful to avoid allergy.