Favorable responses to treatment with 5 mg Sbv /kg/day meglumine antimoniate in patients with American tegumentary leishmaniasis acquired in different Brazilian regions

Introduction: Favorable responses in American tegumentary leishmaniasis (ATL) patients to treatment with 5 mg Sbv/kg/day meglumine antimoniate (MA) has been reported in Rio de Janeiro, but little is known regarding the therapeutic response to low doses in patients from other locations. Methods: A retrospective review of medical records was conducted to compare the therapeutic response to 5 mg Sbv/kg/day MA treatment among 36 patients who acquired ATL in Brazilian states other than Rio de Janeiro (OS group) and 72 patients from Rio de Janeiro (RJ group). Results: One course of 5 mg Sbv/kg/day MA cured 72.8% of 81 cutaneous (CL) and 66.6% of 27 mucosal (ML) leishmaniasis-infected patients: 70% in the CL/RJ group, 81% in the CL/OS group, 50% in the ML/RJ group, and 80% in the ML/OS group. After up to two additional treatment courses at the same dose, 88.9% and 85.2% of the CL and ML patients were cured, respectively. Adverse events were observed in 40% of patients in the CL/RJ group, 57% of the CL/OS group, 58% of the ML/RJ group, and 80% of the ML/OS group. No significant differences were observed in the cure rates or adverse effects between the RJ and OS groups. No patients required permanent discontinuation of treatment due to adverse events. Conclusions: Patients with ATL acquired in both RJ and OS may respond to low-dose MA. While high-dose MA should remain the standard treatment for ATL, low-dose MA might be preferred when toxicity is a primary concern.