ABSTRACT
There have been a few reports of occupational asthma caused by Tetranychus urticae in fruit farmers or greenhouse workers. We report a case of bronchial asthma induced by Tetranychus urticae from a pear orchard in Cheonan city. An 18-year-old female student living around a pear orchard suffered from intermittent cough, rhinorrhea, and dyspnea for the 3 years. Her PC20 -methacholine was 0.15mg/ml, and skin prick test done with 55 inhalant allergens showed negative responses except Tetranychus urticae extract which was prepared with highly parasitized pear leaves. Bronchial provocation test with Tetranychus urticae extract showed a dual asthmatic response. These findings indicate that Tetranychus urticae, which include parasites in fruit trees, herba,ceous plants, and greenhouse cultures, can cause IgE-mediated bronchoconstriction in Korea.