Allergy to cypress pollen
Authors: J.‐C. Dubus, J.‐P. Melluso, A.‐C. Bodiou, N. Stremler‐lebel
Journal: Allergy (2000)

C upressaceae pollen allergy, which has been reported to cause winter conjunctivitis, rhinitis, and asthma in various parts of the world, is on the increase in the Mediterranean area ( 1–3). This study was conducted to determine the frequency of cypress sensitivity in children with asthma in southeast France. Between October 1995 and October 1998, skin prick tests with the major aeroallergens (dust mites, cat and dog danders, Blatella germanica, Alternaria, and mixed grass pollen) and Cupressus sempervirens pollen were performed in 759 children with asthma living in Marseille and the surrounding area. Cypress extracts were 1:20 w/v, while the other extracts were standardized (Laboratoires Stallergènes, France). Atopy, defined by at least one positive skin response to allergens, was found in 469 children (61.8%). Among them, 54 children (39 boys), aged 26–184 months (95.4±40.8), were sensitive to cypress extracts; i.e., 7.1% of all the children with asthma and 11.5% of the atopics. These 54 patients completed a questionnaire concerning asthma, symptoms suggestive of cypress allergy, and place of residence. Except for two children with persistent asthma, the 52 remaining subjects suffered from frequent episodic asthma. They were all treated with inhaled corticosteroids, plus long-acting β2-agonists in 12 cases (22.2%). Asthma was mainly perennial but most of the symptoms were noted in winter, during which colds were described as exclusive triggers of acute episodes in the youngest. Antihistamines were prescribed in 18 children (33.3%) with allergic rhinitis. Two children reported spring conjunctivitis. Thirty-five children (64.8%) lived in apartments in the town center. Frequencies of responses to allergens in the 54 children are shown Fig. 1. Multiple skin sensitivities were found in 48 children (88.9%). The six children with isolated sensitivity to cypress were younger than the multiple-sensitive children (55.1±25.4 months vs 100.4±39.7; Mann–Whitney U-test, P=0.009) and were all living in the town center (P=0.05). It was not possible to correlate respiratory symptoms to cypress sensitivity. Frequencies of responses to allergens in cypress (Cupressus sempervirens)-sensitive children with asthma living in southeast France (n=54). This study demonstrates the relatively high frequency of cypress sensitivity in urban or suburban children with asthma in southeast France. This may be explained by a major exposure to cypress pollen in the atmosphere due to an increased use of cypress as ornamental trees in gardens and parks of Marseille and/or a possible interaction between air pollution and cypress allergens ( 4, 5). The diagnosis of cypress allergy, mimicking seasonal infective respiratory disorder, is usually underestimated ( 3). This problem may be even more important in young children. However, because our children have multiple sensitivities, especially to allergens well known to trigger asthma, cypress sensitivity cannot be considered a direct cause of asthma. Instead, these results confirm that asthma is almost exclusively recorded in cypress-sensitive patients with sensitivity to other allergens ( 1). On the other hand, the surprising findings of young children with isolated sensitivity to cypress force us to be cautious in drawing conclusions.