Antimony in plasma and skin of patients with cutaneous leishmaniasis--relationship with side effects after treatment with meglumine antimoniate.

Objective: To evaluate the levels of antimony in plasma and skin of patients being treated with pentavalent antimonials (Glucantime) and their relationship with side effects.

Methods: We evaluated 19 patients treated endovenously at the conventional dose (20 mg Sb(v)/kg/day), two at a smaller dose (5 mg Sb(v)/kg/day) and three treated intralesionally (up to 4.0 ml/week). During treatment, patients underwent periodic blood exams and were interviewed weekly about the incidence of adverse symptoms. The levels of antimony in plasma and skin samples were determined by Inductively Coupled Plasma with Mass Spectrometry (ICP-MS).

Results: The patients under conventional treatment presented a mean initial antimony plasma concentration of 3.39 microg/l; at the end of treatment, these levels were 0.21 before Glucantime application and 125.8 mg after Glucantime application. The mean antimony level in their skin at the end of the treatment was 9.24 microg/g. The main adverse symptoms were arthralgia and myalgia; laboratory results showed mainly lymphocytosis and eosinophilia.

Conclusions: We found some significant correlations between antimony concentrations, adverse symptoms and laboratory alterations, strengthening the hypothesis of a dose-dependent relationship between antimony concentration in plasma and skin and side effects.