Investigating allergen-specific IgE distribution and correlations in chronic urticaria: a retrospective study in Shanghai, China.

Background: Chronic urticaria (CU) is a persistent skin condition characterized by recurring episodes triggered by diverse allergens and a multifaceted causative nature. The present study aimed to retrospectively explore the distribution patterns and correlations of specific IgE (sIgE) antibodies with various allergens among patients with CU.

Methods: For this purpose, the present study enrolled 820 patients with CU treated at Shanghai Skin Disease Hospital from July 2020 to September 2023. Serum samples were assessed for allergen sIgE antibodies via an immunodiagnostic assay. Chi-square tests were used to examine the differences in allergen sIgE antibody distribution across the sex and age groups. Spearman's correlation analysis was used to investigate the correlations between different allergens.

Results: Among the 820 patients with CU, 705 presented positive results for at least one sIgE antibody. Concerning sex, no significant disparities were observed in food allergen distribution; however, males presented notably higher storage mites and Aspergillus levels than females. Age stratification revealed that adolescents had significantly higher positivity rates for milk, egg yolk, house dust mites, storage mites, cat and dog dander, and timothy grass than adults and elderly patients. The correlation coefficient between house dust mites and storage mites reached 0.81. However, correlations among distinct food allergens mostly remained below 0.3, barring sesame and mixed fruits, which was a weak correlation (r = 0.31). The correlations between food and inhaled allergens ranged from 0.3 to 0.5, suggesting a relatively weak association.

Conclusions: There were no sex disparities in the distribution of ingestible allergens, yet adolescents presented higher positivity rates than the other age groups. The associations among food allergens, as well as food and inhaled allergens, were relatively weak. Trial registration Retrospectively registered.