A 10-Year Retrospective Study on Palladium Sensitivity

Background: Palladium has become an important contact allergen because of increased use in industry, jewelry, and dentistry. Objective: To determine the frequency of palladium allergy in a US patch-test population tested to palladium. Methods: A 10-year retrospective review (1997–2006) was performed on patients sensitive to palladium at the Department of Dermatology, Mayo Clinic, Rochester, MN. Results: A total of 910 patients were tested to a series that included palladium chloride 2% in petrolatum. A palladium-positive patch-test result was noted in 110 patients (12.1%). Of the 106 patients sensitized to palladium who had records available for review, 15.1% had a diagnosis of lichen planus-like eruptions; 13.2%, burning mouth; 27.4%, stomatitis; and 29.2%, hand and body dermatitis. Conclusion: Palladium sensitivity is more common in oral diseases than in skin. We describe a previously unknown high degree of co-reactivity of gold with palladium to the same degree as the known co-reactivity with nickel.