[Prevalence of anaphylaxis to dust mite in human population in Xuzhou]

To study the prevalence of anaphylaxis to dust mite in normal individuals and patients with different allergic disorders in Xuzhou.

By skin prick test (SPT) with Dermatophagoides farinae allergen extract, the prevalence of the normal individuals and OPD patients visiting hospital with allergic symptoms were examined for hypersensitivity to mite. Histamine equivalent criteria were used to evaluate the reactivity rate and the strength of skin response. Results 34 (15.3%) out of 222 pupils and students of different age groups from different levels of schools regarded as the normal population showed positive reaction to the mite allergen with usually only very weak response(+). There were no significant differences between the different age groups (P > 0.05), but it was different between 18.6% (22/118) in females and 11.5% (12/104) in males (P < 0.05). Also the reactivity rate of younger female pupils was higher than that of older ones. Among 515 cases from the OPD patients with allergic symptoms from pediatrics, ENT, respiratory and dermatology departments, 424 (82.3%) were positive with different grades of skin reaction. The rate of strong reactivity (> or = + + +) was 68.6% in allergic children, 63.5% in patients with allergic rhinitis, 41.9% in patients of respiratory department and 25.7% in patients with dermatitis. The allergic children of < or =10 years old showed highest rate of very strong reactivity (+ + + +), the rates declined along with the growing age.

In Xuzhou area the SPT reactivity rate to dust mite for normal individuals was 15.3% with only weak response; while for allergic patients it was 82.3%, 47.9% of them showed strong and very strong responses.