Positive patch test reactions to nickel, cobalt, and potassium dichromate in a series of 576 patients.

In 1988, 633 patients attending our Allergology Center underwent patch testing with the standard series recommended by the Gruppo Italiano Ricerca Dermatiti da Contatto e Ambientali. Of these, 576 patients completed the test correctly and their results were evaluated statistically. Nickel, cobalt, and potassium dichromate were the three most common sensitizers; concomitant positive reactions were present at significant levels. The authors discuss environmental and occupational exposure to contact allergens and correlate the major sites of dermatitis with the sensitivity to each metal in patients of both sexes.