Department of Dermatology and Allergy Centre, Odense University Hospital, University of Southern Denmark, DK-5000, Odense C, Denmark.
Contact Dermatitis. 2013 Nov;69(5):303-10. doi: 10.1111/cod.12096. Epub 2013 Jun 28.
Cushion bush [Leucophyta brownii Cass. = Calocephalus brownii (Cass.) F. Muell.] is an Australian Compositae shrub that has been introduced into Scandinavia as a pot plant. The first case of sensitization occurred in a gardener, and the main allergen was identified as the guaianolide calocephalin.
To present the identification of the main allergen, and to assess the prevalence of sensitization to calocephalin in Compositae-allergic patients.
Calocephalin was isolated from a dichloromethane extract of aerial parts of cushion bush. Calocephalin 0.1% ethanol was included in the plant series in Malmö, Sweden, and Odense, Denmark.
Nuclear magnetic resonance (NMR) analysis of calocephalin resulted in a revision of its chemical structure to 4α-acetoxy-1α,2α-epoxy-5α,10αH-guai-11(13)-en-12,8β-olide. The prevalence of patch test positivity was up to 28% in aimed patch testing. Despite strongly positive patch test reactions, the relevance was unknown in the majority of cases, and only 1 person was occupationally sensitized.
Calocephalin is a potent contact allergen, but, as cushion bush is a low-maintenance pot plant, primary sensitization is most likely to occur through occupational exposure. Positive reactions in Compositae-sensitive persons probably occur because of cross-reactivity, and patients should be warned about contact with cushion bush plants.
缓冲布什（Leucophyta brownii Cass. = Calocephalus brownii（Cass.）F. Muell.）是一种澳大利亚菊科灌木，作为盆栽植物引入斯堪的纳维亚。首例致敏病例发生在一名园丁身上，主要过敏原被鉴定为愈创木烷型卡洛夫辛。
鉴定主要过敏原，并评估 Compositae 过敏患者对卡洛夫辛的致敏率。
从缓冲布什的空中部分的二氯甲烷提取物中分离出卡洛夫辛。卡洛夫辛 0.1%乙醇包含在瑞典马尔默和丹麦欧登塞的植物系列中。
卡洛夫辛的核磁共振（NMR）分析导致其化学结构修订为 4α-乙酰氧基-1α，2α-环氧-5α，10αH-愈创木-11（13）-烯-12，8β-内酯。有针对性的斑贴试验阳性率高达 28%。尽管斑贴试验反应强烈，但在大多数情况下，其相关性未知，只有 1 人职业性致敏。
卡洛夫辛是一种有效的接触过敏原，但由于缓冲布什是一种低维护盆栽植物，主要致敏最有可能通过职业暴露发生。Compositae 敏感人群的阳性反应可能是由于交叉反应引起的，应警告患者接触缓冲布什植物。
