SESQUITERPENE LACTONE MIX CONTACT SENSITIVITY AND ITS RELATIONSHIP TOCHRONIC ACTINIC DERMATITIS - A FOLLOW-UP-STUDY

In a retrospective case note analysis over a 4-year period, 0.9% of al l patients tested with a standard patch test series (65 of 7600) were demonstrated to have clinically relevant responses to a sesquiterpene lactone (SQL) mix. Of these patients, 11 (17%) also had a diagnosis of chronic actinic dermatitis. This group made up 25% of all patients di agnosed as suffering from CAD in this 4-year period. These figures dif fer somewhat from those reported by our group in an initial 4-year per iod immediately following the introduction of the mix into our standar d patch test series, when 1.5% of all patients tested had a clinically relevant response to the SQL mix, including 36% of all patients with a diagnosis of CAD. It is not uncommon for the prevalence of sensitivi ty to an allergen to be overestimated immediately following its introd uction into routine testing. Possible reasons for our findings are dis cussed.