10 years' experience of patch testing with a shoe series in 230 patients: which allergens are important?

Over a 10-year period, 230 patients with foot dermatitis were patch tested to a shoe series of allergens. About 54 (23%) had relevant allergic positive reactions to one or more allergens. The commonest relevant allergens groups were, in order, chromate, medicaments, rubber chemicals, dyes and cosmetic constituents, with the most frequent individual allergens being chromate (4%), neomycin (3%), rubber chemicals (> 3%), paraphenylenediamine (2%) and tixocortyl pivolate (2%). Some allergens previously thought to be important, e.g. certain plastic and adhesive chemicals, did not show any positives over the period of study. In addition, para-tertiary butyl phenol formaldehyde resin was a relatively unimportant allergen in this series. The main practical points to emerge from this study are that, in patients with foot dermatitis, chromate is still the principal allergen, and that medicament and cosmetic allergens may be prominent.