Nonoccupational sensitization to indoor plants

Abstract

Background: Indoor plants can cause imunoglobulin E (IgE)-mediated allergy. We studied sensitization to indoor plants and factors affecting sensitization in an allergy outpatient clinic. Methods/Data base: 205 a topic and 90 nonatopic patients were skin prick tested for sensitivity to 12 common indoor plants. Sera from 34 adult plant-positive patients were immunospot tested. The occurrence of the plants in homes and associated respiratory symptoms were assessed by questionnaire. Results: Of the atopic patients, 39% had positive reactions to the plants; 54% to Ficus benjamina, 36% to Hibiscus rosa sinensis, 35% to Yucca aloifolia, 23% to Dracaena fragrans, and 21% to Asplenium nidus. Of the nonatopics, 2% had skin reactions to the plants. In immunospot studies, 62% of the plant-positive patients showed IgE specific to at least one plant; 44% to Ficus benjamina, 35% to Dieffenbachia picta, and 32% to Hibiscus rosa sinensis and Chamaedorea elegans. Forty percent of patients sensitized to Ficus benjamina and 33% of those sensitized to Dieffenbachia picta reported clinical symptoms. Conclusion: Sensitizati on to indoor plants, particularly to Ficus spp., is commonly detected by skin and immunospot tests in atopic patients. A minority (0-40% for various plants) of prick test-positive patients reported clinical symptoms. Clustering of pollen, vegetable food, and indoor plant sensitivities suggested crossreactivity of allergens. © 2006 Hogrefe & Huber Publishers.