Immediate allergic and nonallergic reactions to Christmas and Easter cacti

• Published in: Allergy (Copenhagen) 1999-05, Vol.54 (5), p.511-516
• Main Authors: Andersen, F, Bindslev‐Jensen, C, Paulsen, E, Andersen, KE, Stahl Skov, P
• Format: Article
• Language: English
• Subjects: Allergens; Allergic diseases; atopy; Biological and medical sciences; conjunctivitis; Conjunctivitis, Allergic - epidemiology; Conjunctivitis, Allergic - etiology; contact urticaria; Histamine Release; Humans; Hypersensitivity, Immediate - epidemiology; Hypersensitivity, Immediate - etiology; immediate hypersensitivity; Immunopathology; Medical sciences; Occupational Exposure; Other localizations; Plant Extracts - adverse effects; plants; Plants - adverse effects; Prevalence; rhinitis; Rhinitis - epidemiology; Rhinitis - etiology; Skin Tests; Surveys and Questionnaires; Urticaria - epidemiology; Urticaria - etiology; work‐related
• ISSN: 0105-4538; 1398-9995
• DOI: 10.1034/j.1398-9995.1999.00016.x

Background: Occupational exposure to Christmas cacti has been reported as a cause of type I allergy. Therefore, the prevalence of immediate‐type mucosal and skin reactions related to cactus exposure was studied in 103 employees in a cactus nursery. Methods: The study was based on a questionnaire followed by clinical examination, skin prick tests (SPT) with standard inhalant allergens and cacti, and a histamine‐release test (HRT/Refix) using fresh cactus extracts as elicitor. Results: The questionnaire was answered by 84 (82%) of the nursery employees, and 63 (61%) were interviewed and skin prick tested; 58 of these were tested with HRT/Refix. Furthermore, 22 healthy controls were included and tested in vivo and in vitro. Cactus‐related contact urticaria and/or rhinoconjunctivitis were reported by 37% of the cactus workers. Based on a combination of positive history, positive SPT, and positive HRT/Refix to cactus, 8% of the cactus workers were allergic to cacti. No noncactus workers or controls were allergic to cacti by these criteria. Testing with fresh cactus material elicited positive SPT and negative HRT/Refix in 27 nursery workers and controls, of whom 12 had immediate‐type skin and mucosal symptoms. Conclusions: Christmas and Easter cacti seemed to be able to induce contact urticaria and rhinoconjunctivitis on both an immunologic and a nonimmunologic basis. Personal atopy was associated with positive reactions to cacti.