Analysis of allergen-specific IgE in children with atopic dermatitis from 2021 to 2023 in a hospital of pediatric in Tianjin City

Abstract

Objective: To explore the distribution of allergen-specific IgE (sIgE) for children with atopic dermatitis in Tianjin City and provide the evidences of clinical diagnosis and treatment. Methods: A retrospective cross-sectional study was conducted to analyze the children who were suspected of atopic dermatitis and tested for serum sIgE in the Tianjin Children's Hospital from March 2021 to February 2023. Using first detection results only, a total of 1 841 serum samples were tested for twenty common allergens. The method was the enzyme-linked immune capture assay. The allergen epidemiological characteristics were statistically analyzed by Chi square test based on the children's characteristics and factors such as different sexes, ages and seasons by the mass data. Results: Among the 1 841 cases, the results showed that 1 247 (67.73%) were sensitized to at least 1 allergen-sIgE, comprising to 49.86% (918/1 841) to food allergen-sIgE and 47.96% (883/1 841) to aeroallergen-sIgE. The top three food allergens-sIgE were egg 32.10% (591/1 841), milk 25.91% (477/1 841) and wheat flour 14.61% (269/1 841); the top three positive rates of aeroallergens-sIgE were house dust 24.33% (448/1 841), alternaria 20.59% (379/1 841) and dermatophagoides farinae 14.83% (273/1 841). The positive rates of food allergens-sIgE were the highest in the 1-3 years old group (64.11%, 434/677) (χ2=122.854, P<0.001), while the positive rates of aeroallergens-sIgE were higher in the 11-14 years old group (71.26%, 62/87) (χ2=134.968, P<0.001). No seasonal difference was revealed in the overall positive rate of food allergen-sIgE and aeroallergen-sIgE (χ2=4.047, P=0.256; χ2=7.549, P=0.056). The positive rates of soybean-sIgE and milk-sIgE were the highest in summer (χ2=11.329, P=0.010; χ2=28.720, P<0.001), whereas alternaria-sIgE and mugwort-sIgE were the highest in summer and autumn, respectively (χ2=8.462, P=0.037; χ2=10.641, P=0.014). Among the 1 841 cases, 32.21% were sensitized to three or more allergens-sIgE. The sIgE concentration levels of egg, milk and house dust were mainly level 1 to 2, and the proportions of level 3 and above were all under 15%; although the positive rates of crab, shrimp, and peanut were low, the proportions of grade 3 and above were all beyond 30%. Children sensitized to alternaria, dermatophagoides farinae, mugwort, and cat dander had higher sIgE concentration levels, which were 68.07%, 49.45%, 56.57% and 47.83% respectively. Conclusions: This study can reflect the epidemic characteristics of allergen-sIgE in children with atopic dermatitis in Tianjin region to a certain extent. Allergen-sIgE positivity in patients differed by age, and there were seasonal differences and grade distribution differences in the positive rates of some allergens-sIgE. It is necessary to reasonably avoid the high-risk allergens according to the epidemiological characteristics and clinical symptoms, which provide valuable information for the prevention, diagnosis and treatment of atopic dermatitis.