Occupational rhinitis and contact urticaria caused by palladium salts

Background: Palladium is a metal used in catalytic converters, electronics, jewelry and dental restorations. Delayed contact allergy to palladium is common and mainly seen together with allergy to nickel. In contrast, immediate allergy to palladium seems to be rare. This is the first case reported of occupational rhinitis due to immediate allergy to palladium compounds confirmed by nasal provocation testing (NPT) and skin prick testing (SPT). A single case report of immediate allergy to palladium compounds confirmed by SPT has previously been published. Objective: A case report of occupational rhinitis and contact urticaria caused by palladium salt exposure in a laboratory assistant working in catalyst industry. Methods: SPTs and open skin application tests were performed with samples of tetra-aminepalladium(II)hydrogen carbonate and tetra-aminepalladium(II)nitrate from the patient's work place. NPTs were performed with tetra-aminepalladium(II)hydrogen carbonate. Results: SPTs and open skin application tests with tetra-aminepalladium(II)hydrogen carbonate and tetra-aminepalladium(II) nitrate were positive. Control SPTs with these palladium salts were negative in 40 volunteers. NPT with tetra-aminepalladium(II)hydrogen carbonate was positive. Conclusions: To our knowledge, this is the first reported case of occupational allergic rhinitis and contact urticaria caused by palladium salts confirmed by nasal provocation testing and skin prick testing. Although immediate allergy to palladium appears to be rare, it is a possible cause of occupational rhinitis and contact urticaria in workers exposed to palladium salts. References: Daenen M. et al. Occupational asthma caused by palladium. Eur Respir J 1999;13:213-216.