Chemicals used for the manufacturing of rubber are known causes of allergic contact dermatitis on the hands. Recent European studies have suggested a decrease in thiuram contact allergy. Moreover, while an association with hand dermatitis is well established, we have recently observed several clinical cases with allergic facial dermatitis to rubber.Objectives
To evaluate temporal trends of contact allergy to rubber accelerators from the European baseline series in a tertiary patch test clinic in Denmark, and examine associations with anatomical locations of dermatitis.Methods
Patch test and clinical data collected in a Danish tertiary dermatology clinic in Gentofte, Herlev, Copenhagen between 1 January 2005 and 31 December 2014 were analysed. The following rubber accelerators or mixtures in petrolatum from the European baseline patch test series were included: thiuram mix 1.0%, mercaptobenzothiazole 2.0% and mercapto mix 1.0%.Results
The overall prevalence of contact allergy to rubber accelerators was 3.1% with no significant change during the study period (Ptrend = 0.667). Contact allergy to thiuram mix was the most prevalent and was significantly associated with occupational contact dermatitis, hand dermatitis, age >40 years and facial dermatitis in adjusted binary logistic regression analysis. Current clinical relevance of contact allergy to thiuram mix was 59.3%. Patients with contact allergy to mercapto mix and mercaptobenzothiazole had a concomitant reaction to thiuram mix in 35.2% (19/54) and 35.4% (17/48) of the cases respectively.Conclusion
Contact allergy to rubber accelerators remains prevalent. Clinicians should be aware of the hitherto unexplored clinical association with facial dermatitis.