Background: Allergic diseases are increasing yearly. We aimed to evaluate the difference in allergen sensitization pattern between adults and children in southern China by analyzing a large sample size of real-life data, and to provide the evidence for formulating the prevention and management strategies.
Methods: Retrospective analysis was conducted on 39,813 serum allergen-specific IgE (sIgE) results collected in southern China from January to December in 2017. Sensitization patterns and how these allergens could lead to the allergic diseases were analyzed for adults and children respectively. The difference of allergen positive rate between groups was calculated using the Chi square test.
Results: The top five most sensitized allergens in southern China were house dust mite (28.1%), cockroach (24.3%), shrimp (19.2%), crab (15.5%) and egg white (9.9%). While cockroach had the highest positive rate in adults (29.2%), the most sensitized allergen in children was house dust mite (29.7%). The positive rates of egg white and cow's milk in children were higher than in adults for the whole year (p < 0.001); whereas for adults, the positive rate to cockroach, shrimp and crab were higher than in children (p < 0.001). The positive rate of house dust mite in coastal cities (32.4%) was higher than that in landlocked cities (24.0%) in children, but in adults, the rate in landlocked cities (31.1%) was higher than that in coastal cities (25.3%). Optimal scaling analysis showed that the sIgEs of crab and shrimp had the closest correlation with cockroach-sIgE (Cronbach's α = 0.891). The positive rate to mold allergens increased from summer to autumn, reaching its plateau in October (6.2%). Patients with skin diseases were found to receive the highest sIgE prescription from doctors (56.9%).
Conclusions: Doctors tend to prescribe more sIgE tests for patients with skin disorders in southern China. In addition to house dust mite, cockroach was found to be another important allergen. Adults with multiple sensitization always showed co-sensitization with shrimp, crab and house dust mite. These should be taken into consideration when giving allergen avoidance advice to patients.
Keywords: Allergen sIgE; Cockroach; Multiple sensitization; Southern China.