Decreasing rates of neomycin sensitization in western Canada

Background: Neomycin contact sensitization rates in North America range from 7% to 13%, whereas in Europe they average approximately 1.9%. Objectives: Given that topical neomycin products are no longer readily available in Canada, the aim of this study was to examine what influence this may have had on neomycin sensitization rates in the 3 western provinces. Methods: On the basis of an observation originally communicated by L. M. Parsons and C. Zhang of the University of Calgary, which suggested significantly reduced rates of neomycin sensitization in Calgary, Alberta, Canada, a multicenter study of patch test results from 5690 patient charts was undertaken. Data from 3 other western Canadian Universities (the University of Saskatchewan, the University of Alberta, and the University of British Colombia) were analyzed. Data were available from 2001 to 2013 for the University of Saskatchewan (except 2006), whereas the University of Alberta and the University of British Columbia had data from 2009 to 2013. Descriptive statistics, trend analysis, and risk estimates were determined using SPSS version 20. Results: Sensitization rates for neomycin have decreased in western Canada and are now similar to those of Europe. Conclusions: This trend is likely influenced by the reduced availability of over-The-counter and prescription neomycin products in Canada.