Objective: To explore the sensitization features of Cypress pollen in urban area of Beijing and analyze the seasonal changes. Methods: Four thousand two hundred and one patients in Department of Allergy of Beijing Shijitan Hospital during January to December 2017 were enrolled in this study and received skin prick test (SPT) of Cypress extract. Cypress sensitization was divided into two types: mono-sensitization and multiple-sensitization. Difference of sensitization rate between age, gender and visiting month was analyzed by chi-square test. Difference of visiting rate and sensitization rate among each month was analyzed by K-W test. Pearson test was carried out for correlation analysis. Results: Positive rate of Cypress pollen was 32.3% (1 358/4 201) in overall patients in which male had a higher positive rate than female (35.6% vs 30.1%, χ²=13.465, P<0.001). The positive rate was highest in age 11-20 years and 31-40 years and then decreased with age (P<0.001). Multi-sensitization was observed in this study with a rate of 27.5% (1 154/4 201) while mono-sensitization of Cypress was only 4.7% (199/4 201). The consultation rate during January to December was positively correlated with SPT positive rate of Cypress pollen (r²=0.715 9, P=0.001). The positive rate varied with season with the highest rate in March (53.0%, 316/596), followed by April (36.6%, 208/568). The season peak of positive rate was observed in adults but not children. Mono-sensitization rate varied with one season peak (spring) while multi-sensitization showed two season peaks (spring and autumn). Conclusion Cypress sensitization is prevalent in urban area of Beijing and is prone to multi-sensitization, which changes with season with the peak in March.

Objective: To investigate the self-reported prevalence, clinical characteristics, complications of allergic rhinitis (AR) and the sensitization of outdoor air pollen allergens in children in the Inner mongolia grassland region. Methods: A multistage, stratified and random clustered sampling with a face-to-face interview survey study in children from 0 to 17 years old was performed together with 10 common allergen skin prick tests (SPT) and measurements of the daily pollen count in 6 regions in the Inner mongolia grassland region from May to August of 2015. SAS 9.4 software was used for data analysis. Results: A total of 2 443 subjects completed the study. The self-reported prevalence of AR was 26.6%. The prevalence of boys was higher than that of girls (28.8% vs 24.3%, χ²=6.157, P<0.05). Subjects from urban areas showed higher prevalence than rural areas (34.7% vs 18.8%, χ²=79.107, P<0.05). There was significant regional difference in the prevalence of AR among the six areas investigated (χ²=221.416, P<0.05). The main clinical symptoms of AR were sneezing (88.2%) and nasal congestion (78.6%). Among combined diseases, asthma accounted for 16.5% (107/650), rhinoconjunctivitis accounted for 47.9% (311/650). The peak season of AR was April and July, with the top SPT positive allergens of Artemisia species and chenopodium in this area. Conclusions The prevalence AR in children in the Inner mongolia grassland region is extremely high. Sneezing is the main clinical symptom. Rhinoconjunctivitis is the most common combined disease. High summer and autumn pollen exposure is the main cause of AR.