Dual dimensions of sensitization: age-stratified and disease-associated sIgE profiles in pediatric eczema and urticaria

Objective To characterize sensitization patterns of allergen-specific immunoglobulin E (sIgE) in children with eczema and urticaria, compare differences by disease type and age group, and provide insights for prevention and treatment strategies. Methods A single-center, retrospective cross-sectional study was performed using serum samples from 4,925 children diagnosed with eczema or urticaria at Henan Children’s Hospital between January 2022 and December 2023. Levels of sIgE to inhaled and food allergens were measured using fluorescence immunoassay. Group differences in sensitization rates were compared using chi-square tests, and Spearman correlation analysis was applied to assess relationships between sIgE levels and clinical parameters. Results The overall positive rate of sIgE was 58.05%, with the positive rate for food allergens (52.93%) significantly higher than that for inhalant allergens (14.05%) ( p 0.001). The main allergen profiles exhibited age-dependent patterns: the sensitization rates for inhalant allergens (dust mite mix, mold mix, inhalant mix) increased with age, while the sensitization rates for food allergens (food mix, egg white, milk) were higher in the younger age group (under 3 years old). The unadjusted comparison showed differences in sensitization profiles: the positive rate of food allergens in children with eczema was significantly higher than that in children with urticaria (55.69% vs. 49.32%, p 0.001), with an unadjusted odds ratio of 1.291. The sensitization rate of inhaled allergens in children with urticaria was significantly higher than that in children with eczema (25.90% vs. 7.57%, p 0.001), with an unadjusted odds ratio of 0.234. Children with eczema and urticaria mainly exhibited low-level sIgE sensitization. High-grade (≥grade 4) positivity was uncommon and primarily associated with specific inhalant allergens. The correlation analysis between sIgE and clinical indicators showed that sIgE to food allergens (such as egg white, wheat, and food mixture) in children with eczema was significantly positively correlated with eosinophil counts, while sIgE to inhalant allergens (such as Dermatophagoides pteronyssinus , Dermatophagoides farinae , mixed dust mite, and mixed grasses) in children with urticaria was significantly positively correlated with hemoglobin concentration. Conclusion This study identified distinct age-dependent sIgE sensitization profiles, while disease-associated differences were attenuated after accounting for age and sex. These findings highlight age as a primary dimension for sensitization risk stratification and underscore the clinical value of integrating sIgE monitoring with other biomarkers, such as eosinophils and hemoglobin.