Abstract: 【Abstract】 Objective To analyze measurement results of serum allergen-specific immunoglobulin E （IgE） in patients with eczema/dermatitis. Methods A retrospective analysis was conducted on serum allergen-specific immunoglobulin E （IgE） levels in 3 051 patients with eczema/dermatitis, who visited the allergy clinic of Huashan Hospital from April 1, 2021 to March 31, 2022. The serum allergen-specific IgE level was detected by using the Phadia allergen detection system, and positive rates of allergens were calculated to determine common inhaled allergens and food allergens in patients with eczema/dermatitis. Comparisons of enumeration data between groups were performed by chi-square test. Results Among the 3 051 patients with eczema/dermatitis, there were 1 412 with atopic dermatitis and 1 639 were other eczema/dermatitis. Detection of serum allergen-specific IgE showed that 1 629 （53%） patients were positive for allergens, and the number of positive allergen-specific IgEs in each patient was 3.0 ± 1.6. The top 3 common inhaled allergens in patients with eczema/dermatitis were Dermatophagoides farinae （904/1 522, 59%）, Dermatophagoides pteronyssinus （891/1 513, 59%） and Alternaria alternata （206/1 068, 19%）, and the top 3 common food allergens were shrimps （251/1 432, 18%）, egg white （165/992, 17%） and cow milk （149/994, 15%）. Among the 3 051 patients, 25 （1%） were aged < 2 years, 571 （19%） aged 2 - 12 years, 285 （9%） aged 12 - 18 years, and 2 170 （71%） were aged > 18 years. The most common food allergens were both egg white in the age groups of < 2 years and 2 -12 years （77%, 37%, respectively）, and were both shrimps in the age groups of 12 - 18 years and > 18 years （31%, 17%, respectively）. Dermatophagoides pteronyssinus and Dermatophagoides farina were the top 2 common inhaled allergens in all age groups, with the positive rate ranging from 36% to 84%; in addition, the positive rate of molds was relatively high in the age group of 2 - 12 years （mold mixture: 37%; Alternaria alternata: 27%）. From April 2021 to March 2022, the positive rate of outdoor allergens ranged from 10% to 15% among outpatients in every month; the positive rates of tree pollen and grass pollen increased from April 2021, and peaked in October 2021. The patients with atopic dermatitis showed a significantly increased positive rate of allergens （73%） compared with those with other eczema/dermatitis （37%, χ2 = 389.36, P＜0.001）, and the rank of common allergens in the patients with atopic dermatitis was basically the same as that in those with eczema/dermatitis. Conclusions The common allergens were Dermatophagoides farina, Dermatophagoides pteronyssinus and Alternaria alternata in the patients with eczema/dermatitis. Food allergy was more common in infant patients, and inhalation allergy was more common in child, adolescent and adult patients. The positive rate of allergen-specific IgEs was markedly higher in the patients with atopic dermatitis than in those with other eczema/dermatitis.

Key words: Eczema, Dermatitis, Dermatitis, atopic, Allergens, Serum specific immunoglobulin E