Objective: To study the atopy spectrum and its related factors in 1 to 3 years old children with allergic rhinitis.
Methods: Ninety-six children with allergic rhinitis, aged between 1 and 3 years old, referred to ENT department of Beijing Children's Hospital between August 2009 and November 2010 were retrospectively reviewed. Data were recorded for patients' age, age stratification, sex, the age of first symptom, the duration of history, and the allergic history of children, the allergic history of parents. The screening tests on inhalant and food allergens were conducted by immunoblot assay using the Allergy Screen system. The total serum IgE level was also measured. The distribution of the inhalant and food allergens was summarized. The influence of the clinical characteristics was analyzed according to the age subgroup determined by month, allergen category and positiveness of eczema or asthma. Logistic regression was used to analyze the relationship of clinical characteristics and allergen spectrum.
Results: The total positive rates of allergic screening test rate were 81.3%. The inhalant and food allergens were 62.5% and 53.1% respectively. The commonest allergy was mixed fungal (50.0%), followed by milk (34.4%), lamb (31.3%), beef (26.0%), dust mite (21.0%), wheat (18.8%), mugwort (12.5%), egg white or egg yolk (11.5%).62.5% of patients could be diagnosed as AR, the remaining could be diagnosed temporarily as non-allergic rhinitis temporarily. Single factor analysis of clinical characteristics in different subgroup determined by month showed that: inhalant allergen (positive/negative) (χ2=13.699, P=0.001), father suffered from AR (χ2=14.060, P=0.001), and father or mother suffered from AR (χ2=7.396, P=0.025) were statistically significant at three monthly age groups. The personal history of eczema (OR=3.143, P=0.034) might increase the possibility of sensitization to allergens. The personal history of eczema (OR=3.125, P=0.015) and the total serum IgE level>200 IU/ml (OR=3.119, P=0.030) might increase the possibility of sensitization to inhalant allergens. No clinical features for food allergen sensitization was statistically significant. There was no significant difference in positive rates between inhalant and food allergens groups. The presence of inhalant allergens (OR=3.594, P=0.046), insect bites dermatitis (OR=11.941, P=0.002) were the risk factors for positiveness of eczema or asthma, and the father with AR (OR=0.251, P=0.040) as protective factors.
Conclusions: Inhalant and food allergens all can be sensitized in the children with AR symptoms between 1 to 3 years old, and the positive rate of inhalant group is slightly higher. The differences of the inhalant allergen (positive/negative) and father suffered from AR are statistically significant at three monthly age groups. The history of eczema is the risk factor for allergen screening positive. Serum total IgE>200 IU/ml and eczema history are risk factors for inhalant allergen screening positive. The factors of inhalant allergens, insect bites dermatitis and father suffered from AR relate to any positive of eczema or asthma.