Exacerbation of pustulosis palmaris et plantaris after topical applicationof metals accompanied by elevated levels of leukotriene B-4 in pustules

Background: Pustulosis palmaris et plantaris (PPP) is a chronic inflammator y disease consisting of polymorphonuclear leukocyte infiltration, and is of ten exacerbated by focal infections such as tonsillitis. In some cases, met al allergy has been reported. Objective: The purpose of this study was to evaluate (1) the significance o f metal allergy in the formation of pustules, and (2) the participation of leukotriene (LT) B-4 in the formation of pustules of PPP. Methods: Patch tests with metals were performed on 7 patients with PPP, and both pustular and plasma levels of LTB4 were measured in these 7 patients before and 48 hours after metal patch tests. Results: Palmoplantar pustules were exacerbated after the metal patch tests in all 7 patients. The mean levels of LTB4 in plasma and pustules of the v olar surface at 48 hours after the metal patch tests were significantly hig her than those before the metal patch tests. Conclusion: Metals can be important in the pathogenesis of PPP by contribut ing to the induction of high LTB4 concentration in the pustules.