RT Journal Article SR Electronic T1 Occupational asthma due to IgE mediated allergy to the flower Molucella laevis (Bells of Ireland) JF Occupational and Environmental Medicine JO Occup Environ Med FD BMJ Publishing Group Ltd SP 701 OP 703 DO 10.1136/oem.60.9.701 VO 60 IS 9 A1 W M A J Miesen A1 S van der Heide A1 H A M Kerstjens A1 A E J Dubois A1 J G R de Monchy YR 2003 UL http://oem.bmj.com/content/60/9/701.abstract AB Background: About 25% of greenhouse flower and/or ornamental plant growers sensitised to workplace flowers or moulds have occupational asthma, a disease that is suffered by 8% of the growers who cultivate these crops. Aim: To document a case of occupational asthma due to IgE mediated allergy to the flower Molucella laevis. Methods and Results: There was a history of work related seasonal asthmatic and rhinoconjunctivitis symptoms in a Molucella laevis grower. Bronchial obstruction following exposure to Molucella laevis was documented by a fall in FEV1 from 89% to 73% of predicted during seasonal exposure to Molucella laevis. Daily PEF measurements showed a fall from 500 to 250 l/min during this period following withdrawal of inhaled steroids. Bronchial reactivity to inhaled methacholine was increased (PC20 1.45 mg/ml). Confirmation of sensitisation to Molucella laevis flower pollen extract was done using an SPT and by demonstration of Molucella laevis specific serum IgE (18 IU/ml; class 4). Specific inhalation challenge with Molucella laevis extract provoked an early and late asthmatic reaction (EAR and LAR) with a fall in FEV1 compared with control day of 40% and 53% respectively, with associated 5.1-fold increase in absolute sputum eosinophil cell counts and 2.9-fold increase in neutrophil cell counts.