RESUMO
BACKGROUND: Persulfates have been reported to cause both delayed-type and immediate skin reactions. They may also cause immediate reactions of the mucous membranes of the bronchial system through inhalation, leading to asthma and rhinitis. Anaphylactic reactions caused by contact with persulfates are rare. The mechanism of immediate reactions caused by persulfates is unclear. OBJECTIVES: To report 2 cases with systemic reactions after skin contact with persulfates, and to propose a test protocol for diagnosing immediate reactions caused by persulfates. METHODS: Prick tests with serial dilutions of ammonium and potassium persulfate were performed. Patch tests were also performed with the two agents. Persulfate-specific IgE was detected with two different IgE immunoblotting techniques. RESULTS: Prick tests were positive with ammonium and potassium persufate, but no specific IgE was detected in the serum. Patch tests showed early positive reactions to both persulfates in 1 patient. CONCLUSIONS: Prick tests and patch tests can be valuable in the testing of patients with a suspicion of an immediate-type reaction caused by persulfates. The mechanism of these reactions remains unclear.