Are concomitant patch test reactions to epoxy resin and BIS‐GMA indicative of cross‐reactivity?

BACKGROUND: Despite rare simultaneous exposure, concomitant sensitisation to bisphenol A diglycidyl methacrylate (BIS-GMA) and epoxy resin frequently occurs. Immunological cross-reactivity has not been proven by animal experiments so far. OBJECTIVE: Our objective was to examine cross-reactivity epidemiologically by analysing data of the Information Network of Departments of Dermatology (IVDK). PATIENTS/METHODS: From 2001 to 2005, 3,777 patients were patch tested with epoxy resin and BIS-GMA in the IVDK. We retrospectively analysed concomitant reactions to these allergens and to BIS-GMA and selected methacrylates. Additionally, we compared clinical characteristics of patients reacting to both, epoxy resin and BIS-GMA, with those of patients reacting to epoxy resin or BIS-GMA only. RESULTS: 185 patients reacted to epoxy resin, and 40 to BIS-GMA. Of the latter, 34 reacted to epoxy resin. There was no difference concerning exposure between the above-mentioned groups of patients. Concomitant reactions to BIS-GMA and methacrylates hardly ever occurred. CONCLUSIONS: Considering the fact that very few patients had been potentially exposed to BIS-GMA and that 85% of those reacting to BIS-GMA also reacted to epoxy resin, we conclude that our data are presumably indicative of immunological cross-reactivity. A verification of this hypothesis by animal experiments would be promising.