Prevalence of food allergen and aeroallergen sensitization among children in Sichuan province

Abstract

Food allergen and aeroallergen sensitization are common allergic diseases worldwide, with widely varying estimates of prevalence in children. Our study investigated the characteristics of ingestion and inhalation allergy among children from Sichuan province in Southwest China, so as to get public awareness of these disorders.A total of 1722 children between 0 and 14 years' old were enrolled in this study. They were outpatients in the West China Second University Hospital during June 2019 to September 2019. Serum specific IgE specific to 10 types of food allergen and 10 types of aeroallergen were estimated. Nutrition indicators were tested by electrochemical luminescence.59.70% children were allergic to at least 1 allergen, comprising 24.90% to aeroallergen and 38.81% to food allergen, respectively, whereas 36.28% children were allergic to both aeroallergen and food allergen. Milk was the most common food allergen, and egg came in second place. With regard to aeroallergen, house dust mite held the maximum proportion (65.02%), whereas dust mite followed behind. Inhalation allergy was more commonly seen in boys than girls. Bronchitis was the most common symptom of both allergies. In addition, the highest incidence age for children to be sensitive to food allergen and aeroallergen were 0∼2 years' old and 3∼5 years' old, respectively. It is worth mentioning that there was no significant difference in nutritional status between children with or without allergic diseases.Our findings reveal that milk, egg, house dust mite, and dust mite are the most common allergens among children in Sichuan province. Boys are more susceptible to aeroallergen than girls. Furthermore, the prevalence of ingestion and inhalation allergy varies from different age groups, and has no correlation with nutritional status. In brief, the analysis of the pattern of food allergen and aeroallergen sensitization is invaluable to effective diagnosis and treatment of allergic diseases.

Figure 1

General situation of children's allergy in Sichuan province. (A) 59.70% (1028/1722) children in Sichuan province were allergic to at least 1 allergen. (B) For those children with allergies, 36.28% were hypersensitive to both aeroallergen and food allergen. 24.90% children were hypersensitive to aeroallergen alone, whereas 38.81% children were hypersensitive to food allergen alone. (C) Bronchitis (18.29%), cough (16.93%), and rash (13.13%) were the top 3 allergy symptoms. (D) For food allergens, milk and egg were the most important food allergens, causing 73.96% and 54.79% allergies, respectively. (E) As for aeroallergen, house dust mite (65.02%) and dust mite (63.12%) lead to most of the allergies, followed by house dust (48.33%) inducing nearly half of the allergies. (F) The average food allergen intensity scores for 0∼2, 3∼5, 6∼8, 9∼11, and 12∼14 years’ age group were 2.33 ± 0.12, 3.51 ± 0.13, 4.06 ± 0.17, 4.40 ± 0.32, and 4.10 ± 0.46, respectively. Although the average aeroallergen intensity score for 0∼2, 3∼5, 6∼8, 9∼11, and 12∼14 years’ age group were 1.69 ± 0.05, 1.90 ± 0.08, 1.46 ± 0.12, 2.47 ± 0.49, and 2.06 ± 0.55, respectively. Data presented are the mean ± SEM (analysis of variance, P < .001). These results show that allergies to food allergen and aeroallergen are common among children in Sichuan province. One child may be allergic to different allergens. Milk and egg are the most common food allergens. Besides house dust mite, dust mite and dust are the most common aeroallergens. The allergic intensity of aeroallergen is stronger than that of the food allergen.

Figure 2

Allergy characteristics of children in different sex and age groups. (A) The incidence of hypersensitive to aeroallergen in boys was 38.72%, which was greater than that of girls (33.24%) (χ² test, P = .02). However, the difference of the incidence of hypersensitive to food allergen was not statistically significant in different genders. (B) The incidence of inhalation allergy was highest and statistically significant in children aged 3 to 5 years. The line stands for the variation trend. (C) The ratio of ingestion allergy was highest in the 0∼2 years’ group and then decreased with age. The line stands for the variation trend. (D) Total protein (TP), albumin (Alb), hemoglobin (Hb), calcium (Ca), and vitamin D (VitD) were slightly higher in children with allergies than in healthy children, but the difference was not statistically significant. These results indicated that the nutritional status is not the cause of allergies affecting children in the Sichuan province. (^∗P < .05, ^∗∗P < .01 and ^∗∗∗P < .001).