Patch testing with fragrance mix II: results of the IVDK 2005–2008

Background: The fragrance mix (FM I), established in 1977, detects the majority, but not all cases of contact allergy to fragrances. Based on European research 2002/2003, fragrance mix II (FM II) was developed to supplement FM I. In 2005, the German Contact Dermatitis Research Group (DKG) added FM II to their baseline series. Objectives: To evaluate reactions to FM II and its constituents in routine patch testing. Methods: Retrospective data analysis of the Information Network of Departments of Dermatology (IVDK), 2005–2008, of patch test results with FM II and its constituents. Results: A total of 35 633 patients were patch tested with FM II as part of the DKG baseline series. Of these, 1742 (4.9%) reacted positively. Concomitant reactions to FM I were observed in 41.9% of the patients reacting to FM II. In 367 FM II‐positive patients, a full breakdown test of the mix was performed. Of these, 47.7% reacted to hydroxyisohexyl 3‐cyclohexene carboxaldehyde, 16.1% to citral, 11.4% to farnesol, 3.8% to hexyl cinnamal, 2.7% to coumarin, and 2.5% to citronellol. Conclusions: FM II is an important screening and diagnostic tool to detect fragrance allergy. Hydroxyisohexyl 3‐cyclohexene carboxaldehyde is the most important fragrance allergen in FM II.