A review of 241 subjects who were patch tested twice: could fragrance mix I cause active sensitization?
Department of Cutaneous Allergy, St John's Institute of Dermatology, St Thomas' Hospital, London SE1 7EH, U.K.
Background Active patch test sensitization is an uncommon phenomenon which may have undesirable consequences for those undergoing this gold-standard investigation for contact allergy. Objectives To perform a retrospective analysis of the results of 241 subjects who were patch tested twice in a monocentre evaluating approximately 1500 subjects per year. Methods Positivity to 11 common allergens in the recommended Baseline Series of contact allergens (European) was analysed: nickel sulphate; Myroxylon pereirae; fragrance mix I; para-phenylenediamine; colophonium; epoxy resin; neomycin; quaternium-15; thiuram mix; sesquiterpene lactone mix; and para-tert-butylphenol resin. Results Only fragrance mix I gave a statistically significant, increased rate of positivity on the second reading compared with the first (P = 0.011). This trend was maintained when separately analysing a subgroup of 42 subjects who had been repeat patch tested within 1 year; this analysis was done to minimize the potential confounding factor of increased usage of fragrances with a wide interval between both tests. To reduce the confounding effect of age on our data, we calculated expected frequencies of positivity to fragrance mix I based on previously published data from our centre. This showed a marked excess of observed cases over predicted ones, particularly in women in the age range 40-60 years. Conclusions We suspect that active sensitization to fragrance mix I may occur. Similar published analysis from another large group using standard methodology supports our data.
PMID: 18205877 [PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/18205877?dopt=AbstractPlus
