Fragrance allergy in patients with eczema and its relevance to contact allergy to Qingpeng ointment

Objective To evaluate the sensitivity to fragrance mixture,colophony and Qingpeng ointment in patients with eczema by a patch test,and to assess the relationship between patch test reactions to fragrance mixture or colophony and those to Qingpeng ointment,so as to determine if patients clinically reactive to fragrance mixture and colophony can apply Qingpeng ointment safely.Methods Patch testing was carried out with European standard series and raw materials of Qingpeng ointment in outpatients with eczema or dermatitis.The clinical relevance of patch test results was analyzed based on clinical medical history and a follow-up study.Data were processed with the SPSS 17.0 software.Constituent ratio was used for statistical description,and intergroup comparison was carried out by chi-square test and Fisher's exact test.Results Totally,333 patients (including 48 males and 285 females) were consecutively enrolled in this study,with an average age of 35.9 years (range,14-77 years).The positivity rate of patch test with fragrance and colophony was 3.8％ and 2.7％ respectively.Five (1.5％) patients showed positive patch test reactions to Qingpeng ointment but no clinical relevance was identified.No significant difference was observed in the positivity rate of patch test with Qingpeng ointment between patients with positive patch test reactions to fragrance mix or colophony and those without (5.9％ vs.1.6％,Fisher's exact test,P ＞ 0.05).Conclusions Fragrance allergy is common in patients with eczema,but the positivity rate of patch test with Qingpeng ointment is low (1.5％) with no clinical relevance.No association is found between the allergy to fragrance mixture and colophony and that to Qingpeng ointment,which deserves further study. Key words: Eczema;  Qingpeng ointment;  Perfume;  Anaphylaxis