University of California, San Diego, San Diego, CA, USA.
Dermatitis. 2009 Nov-Dec;20(6):E16-20.
A 34-year-old male experienced severe allergic contact dermatitis from 12-hydroxystearic acid in a lip balm and from hydrogenated castor oil in an underarm deodorant. He also had a positive patch-test reaction to bis-diglyceryl polyacyladipate-2, which is present in the implicated lip balm and which itself contains 12-hydroxystearic acid. He was also incidentally found to have contact allergy to ricinoleic acid and castor oil. Ricinoleic acid is the principal fatty acid in castor oil, whereas 12-hydroxystearic acid is the principal fatty acid in hydrogenated castor oil. These two fatty acids are each 18-carbon 12-hydroxylated fatty acids, differing only in degree of saturation. The lack of patch-test reactivity to the analogous nonhydroxylated fatty acids, stearic acid (C18:0), and oleic acid (C18:1) indicates that 12-hydroxylation was required for allergenicity in this patient. In addition, serial dilution testing demonstrated that saturation of the hydroxylated C18 fatty acid enhanced its allergenicity.
一位 34 岁男性因唇膏中的 12-羟基硬脂酸和体香剂中的氢化蓖麻油而发生严重的过敏接触性皮炎。他的斑贴试验还对双二甘油聚酰基己二酸酯-2 呈阳性反应，该物质存在于有问题的唇膏中，而它本身含有 12-羟基硬脂酸。他还偶然被发现对蓖麻酸和蓖麻油有接触过敏。蓖麻酸是蓖麻油中的主要脂肪酸，而 12-羟基硬脂酸是氢化蓖麻油中的主要脂肪酸。这两种脂肪酸都是 18 碳 12-羟基脂肪酸，只是饱和度不同。对类似的非羟基化脂肪酸硬脂酸（C18:0）和油酸（C18:1）的斑贴试验无反应表明，在该患者中，12-羟基化是产生过敏的必要条件。此外，系列稀释测试表明，羟基化 C18 脂肪酸的饱和增强了其致敏性。
