Allergic reactions, including asthma, to the pineapple protease bromelain following occupational exposure

Abstract

A 58 yr old pharmaceutical worker regularly developed asthma and rhinitis when handling bromelain, a purified protease of pineapple (A. comosus), where she had been employed for about 10 yr. RAST [radioallergosorbent test] and prick test showed strong positive reactions to bromelain. Inhalation test with 0.03 mg bromelain and peroral challenge by ingestion of 190 g pineapple resulted in asthmatic reactions; the latter challenge was accompanied by gastrointestinal symptoms. Of 6 workers sensitized to papain, 5 showed positive RAST and skin test results to bromelain; 2 showed immediate asthmatic reactions after bronchial challenge with bromelain. Of 6 asthmatics not exposed to airborne proteases but probably to these as constituents of foods, 2 had positive skin test results and 8 had positive RAST results to bromelain; in no case was there clear evidence for clinical sensitization. Bromelain is capable of inducing Ig[immunoglobulin]E mediated respiratory and gastrointestinal allergic reactions. There may be immunological cross-reaction between the 2 plant proteases bromelain and papain in human subjects.