Primin sensitization in north-eastern Italy: a temporal trend from 1996 to 2012.

BACKGROUND Primin is the main contact allergen found in the ornamental plant Primula obconica Hance. OBJECTIVE To analyse the temporal trend of sensitivity to primin in north-eastern Italy and to evaluate the associations with occupations in our geographical area. METHODOLOGY From 1996 to 2012, 24 052 consecutive patients with suspected allergic contact dermatitis were patch tested in north-eastern Italy. Individual characteristics were collected through a standardized questionnaire in eight departments of dermatology or occupational medicine. RESULTS The overall prevalence of primin sensitization was 1.9%; the prevalence was significantly higher in women (2.6%) than in men (0.5%). The Pordenone area had the higher prevalence of sensitization, which reached 6% in 1999-2001. We found a significant association between primin sensitization and household workers [odds ratio (OR) 2.3; 95% confidence interval (CI): 1.61-3.35], retired people (OR 1.8; 95%CI: 1.22-2.81), woodworkers (OR 2.1; 95%CI: 1.10-6.18), and chemical industry workers (OR 2.9; 95%CI: 1.05-8.29). CONCLUSION Our study showed that contact allergy to primin is still relevant in north-eastern Italy. The frequency of sensitization is decreasing, but for retired and household workers it is still >4%. Our results suggest the need to promote the use of primin-free P. obconica in Italy.