Abstract:

Lu Xueyan*, Wang Dexu, Jiang Jing, Li Qinfeng, Zhou Xiao, Chen Li, Li Hongyi, Li Bin, Jia Jianqin, Deng Danqi, Zhang Yuhuan, Li Linfeng. *Department of Dermatology, Peking University Third Hospital, Beijing 100191, China Corresponding author: Li Linfeng, Email: zoonli@tom.com 【Abstract】 Objective To identify common allergens in patients with eczema or dermatitis by using serum IgE tests, and to explore their clinical significance. Methods A retrospective study was carried out on eczema or dermatitis patients with at least one positive serum IgE test result from 10 hospitals in China. Results Totally, 458 patients were included in this study with an average age of 28.13 ± 23.11 years. Of these patients, 209 （45.63%） were male, and 249 （54.37%） were female. The top three allergens were cockroaches （180/458, 39.30%）, dust mite mix（152/458, 33.19%） and peanuts （116/458, 25.33%）. Polysensitization （sensitization to more than one allergen） was observed in 89.66% （26/29） of patients with atopic dermatitis and 86.84%（33/38） of patients with facial eczema. Moreover, the rate of polysensitization was significantly higher in patients with generalized lesions than in those with circumscribed lesions （80% （88/110） vs. 70.40% （245/348）, χ2 = 3.880, P = 0.049）. The positive rate of specific IgE against inhaled allergens was highest in the age group of 11 - 20 years （39/43, 90.70%） , while the specific IgE against milk （26.53%, 26/98） and beef （19.39%, 19/98） was mainly observed in children aged less than 3 years. In addition, patients in northern areas showed increased positive rates of specific IgE to mugwort （10.35% vs. 1.61%, χ2 = 4.917, P < 0.05）, cockroaches （42.42% vs. 19.35%, χ2 = 11.959, P < 0.05）, milk （14.39% vs. 3.23%, χ2 = 5.958, P < 0.05）, soybeans （13.89% vs. 3.23%, χ2 = 5.594, P < 0.05）, beef （11.36% vs. 1.61%, χ2 = 5.641, P < 0.05） and fresh-water fish （13.38% vs. 3.23%, χ2 = 5.235, P < 0.05） compared with those in southern areas. Conclusions Cockroaches are a common allergen in patients with eczema or dermatitis, and their clinical significance is worthy of further study. Polysensitization seems to be more frequent in patients with facial eczema or atopic dermatitis. Age is an important factor influencing allergen sensitization, and there is a regional difference in the distribution of common allergens.