Compositae mix is a more sensitive test for Compositae dermatitis than thesesquiterpene lactone mix

Over the past 2 decades, Compositae dermatitis has increasingly been recogn ized as a cause of exposure-pattern dermatitis. The introduction of the ses quiterpene lactone (SL) mix as a screening test has contributed to this imp roved recognition. However, there is growing evidence that the SL mix fails to detect a substantial number of genuine Compositae allergies. We therefo re investigated whether another screening reagent (the Compositae mix) migh t be more sensitive in detecting cases of Compositae allergy than the SL mi x. Over a 1-year period, we tested 656 consecutive unselected patch test pa tients to both SL mix and Compositae mix. 31 patients were found to have ge nuine Compositae allergies. Of these, 28 had reacted to the Compositae mix but only 13 had reacted to the SL mix. The Compositae mix failed to detect only 2 genuine Compositae allergies, whereas the SL mix missed 17 such alle rgies. On the other hand, the Compositae mix led to 9 irritant reactions, w hile there was only 1 irritant reaction with the SL mix. We conclude that C ompositae dermatitis is still being underdiagnosed with the current screeni ng method, and that the Compositae mix is significantly more sensitive in d etecting Compositae allergy than the SL mix.