Differences in food sensitization patterns between infants/toddlers and children: a cross-sectional study of patients aged 0–14 years in urban China

Objective With rapid urbanization in China, the prevalence of food allergies among children has significantly increased. To explore the evolution of sensitization patterns in early life, this study aimed to systematically compare allergen profiles among infants/toddlers and children with food sensitization to provide evidence-based support for implementation. Method This study analyzed sensitization to 7 common food allergens in 947 patients aged 0–14 years (402 children aged 4–14 years and 545 infants/toddlers aged 0–3 years) with food sensitization in urban of China. Results In children, spring and autumn visits were the more common (all at 26.4%), and the highest sensitization rate was egg whites (49.0%), followed by hazelnuts (43.8%), and milk (32.6%). In infants/toddlers, winter visits were the most common (28.3%), and the highest sensitization rate was egg white (75.4%), followed by milk (55.4%) and wheat (15.2%). Meanwhile, the positive rates for egg whites (75.4% vs. 49.0%, P 0.001) and milk (55.4% vs. 32.6%, P 0.05) were significantly higher in infants/toddlers than in children. Positive rates of hazelnut (43.8% vs. 11.6%, P 0.001) were significantly higher in children than in infants/toddlers. The distribution of different allergens also varies among infants/toddlers, and children during different seasons. Infants/toddlers with skin symptoms had the highest positivity rates for shrimp (46.9%) and beef (45.6%), whereas children had the highest positivity rates for codfish (27.3%) and shrimp (22.4%). Compared with children (34.1%), 44.6% of infants/toddlers were co-sensitized to ≥2 allergens. Optimal scale analysis revealed no fixed pattern of sensitization among infants/toddlers. If it was sensitization to one of the allergens, it was highly likely to be co-sensitized to others (Cronbach's α = 0.924). However, in children, one group was primarily sensitized to egg whites, codfish, and shrimp, whereas the other was primarily to milk, wheat, and hazelnuts (Cronbach's α = 0.876). Conclusion Children of different ages showed distinct sensitization characteristics, and the sensitization pattern of children may have developed from that of infancy. These findings support the adoption of differentiated allergy risk management and prevention strategies at different life stages.