Distribution and Determinants of Dermatophagoides Mites Sensitization ofAllergic Rhinitis and Allergic Asthma in China

BACKGROUND: The implementation of allergen immunotherapy (AIT) requires extensive knowledge of allergen distribution in the region to identify high-risk regions for AIT utilization. However, the geographical distribution patterns of the major Dermatophagoides allergens in China remain unclear despite the increasing prevalence of these allergens. METHODS: We performed comprehensive database searches of articles demonstrating the distribution patterns of Dermatophagoides-sensitized allergic rhinitis (AR) and allergic asthma (AA) in China, published between 1990 and 2017. RESULTS: We retrieved 163 articles encompassing 114,302 allergen-positive cases to generate the distribution maps. The rate of sensitization to Dermatophagoides pteronyssinus(D. pteronyssinus)and Dermatophagoides farinae (D. farinae) was similar in patients with AR (75.1 vs. 75.2%, p > 0.05) but not in those with AA (78.5 vs. 77.7%, p = 0.041). Patients with AR and AA shared similar regional distribution patterns of both D. pteronyssinus and D. farinae sensitization, which were highest in the southern and central parts of China and lowest in the northern regions, especially in the Northwest. The overall rate of sensitization to D. pteronyssinus and D. farinae was significantly higher in patients with AA (p < 0.001). Additionally, the annual mean temperature and humidity were the 2 major determinants of D. pteronyssinus and D. farinae sensitization in AR and of D. pteronyssinus sensitization in AA, whereas the annual mean temperature was the sole determinant for D. farinae sensitization in AA. CONCLUSION: These findings may inform clinicians of the strategies for the prevention of Dermatophagoides sensitization and may be of benefit to the future clinical management of allergic diseasesassociated with sensitization to Dermatophagoides mites.