A new trend in sensitization to cockroach allergen: A cross-sectional study of indoor allergens and food allergens in the inland region of Southwest China.

Background: Despite the increasing prevalence of allergic disease, large-scale studies to investigate allergen sensitization have rarely been conducted in the inland region of Southwest China.

Objective: This study aimed to investigate the trend of allergen sensitization in mainland China from 2016 to 2017.

Methods: During the 2-year study period, from 2016 to 2017, the serum samples of 7,759 allergic patients collected from 38 hospitals in Yunnan were detected the specific immunoglobulin E (sIgE) against 8 indoor and food allergens, namely, house dust mite, cockroach, dog dander, mold mix, egg white, milk, crab, and shrimp. The polysensitization patterns were analyzed through cluster analysis, and the relationship between cockroach and other indoor and food allergens was analyzed.

Results: Allergen sIgE positivity was prevalent in 45.6% of the population. Cockroach was the most common allergen (27.0%), followed by house dust mite (25.6%), shrimp (18.8%) and crab (15.6%). Three polysensitization clusters were identified: cluster 1): egg white/milk; cluster 2): crab/shrimp/cockroach/house dust mite/dog dander; and cluster 3): mold mix. The sIgE levels and sensitization rates to house dust mite, crab, and shrimp increased with the level of cockroach sIgE (P < 0.05).

Conclusions: Based on big data in the real world, we found that there is a new trend in common allergens in Southwest China, where house dust mite is the only available reagent of specific immunotherapy. Cockroaches may become another major allergen in mainland China in the future, and clinicians should be aware of this.