Unexpected sensitization routes and general frequency of contact allergies in an elderly stented Swedish population

Contact allergy to stent material has been proposed to be a risk factor for restenosis, after percutaneous transluminal coronary angioplasty (PTCA) and stenting. Information on the general frequency of contact allergy in the elderly population is scarce and knowledge of possible sensitization routes is important to investigate. The aim of this study was to investigate contact allergy to stent materials and other allergens. Here we report our findings on the frequency of contact allergies apart from those from stent material. In this retrospective study, we patch tested an elderly population, treated with PTCA and stented, with our standard series. A dermatitis population served as controls. We found a high frequency of contact allergy in both groups but a greater 'contact allergy burden', with generally higher frequencies for contact allergens, in the dermatitis patients as expected. Myroxylon pereirae and caine mix were apart from metals exceptions with statistically significant higher frequencies (P < 0.01) for the stented patients. Contact allergy to nonmetal sensitizers is common in an elderly Swedish stent population although, on the whole, substantially less than in an age and sex-matched dermatitis population. The findings indicate the importance of the oral mucosa for sensitization. In a general population that has been treated with a special medication/treatment procedure, contact allergies not suspected (such as to M. pereirae and to the metals) might suddenly peak. This underlines the importance of a careful evaluation of new products and routines with regard to contact allergies in the population.