Background: Patch testing to fragrances is an important step in the diagnosis of fragrance allergy.
Objectives: To determine the usefulness of adding propolis to the European standard series to test for fragrance allergy.
Patients and methods: A total of 2660 consecutive patients were patch tested with a standard patch test series; 747 suspected of fragrance allergy were tested further with a special fragrance series.
Results: The positive results to the standard series in 2660 patients were: fragrance mix 243 (9.1%), Myroxylon Pereirae [balsam of Peru] 144 (5.4%), colophony 32 (1.2%); these fragrance mixtures are used as screening substances for fragrance allergy in the European standard series. Propolis, also known as bee's glue, was also an important allergen in this locally revised standard series (n = 35, 1.3%). Positive reactions to the aforementioned allergens were associated significantly among each other (P < 0.01, chi2-test) and did not differ between the sexes. The primary locations of dermatitis in patients with a positive test to one or more fragrance allergens (n = 162) among those suspected of fragrance allergy (n = 747) were: face 46.9%, hands 23.5%, neck 17.9%, axillae 12.3%; 92 of the 747 patients suspected of fragrance allergy had positive skin tests to the special fragrance series comprising the eight constituents of the fragrance mix (most frequent: isoeugenol 5.4%, oakmoss absolute 5.0%, eugenol 2.5%) and 14 other fragrance allergens (most frequent: clove oil 1.6%, lemon grass oil 0.8%, cedar wood oil 0.7%). The additional value of propolis as another screening substance for fragrance allergy in these patients was low. The likelihood of a reaction to one or more of the extra fragrance allergens increased with the number of reactions to fragrance screening allergens in the standard series.
Conclusions: The number of positive reactions to fragrance screening allergens in a standard patch test series may be used as a rule of thumb for predicting a positive outcome of a more detailed testing to fragrances. Propolis is an important allergen in its own right but its value as a screening substance for fragrance allergy is limited.