Treatment Outcome of the Drug-resistant Zoonotic Cutaneous Leishmaniasis by Glucantime

BACKGROUND: Resistance of Leishmania species to antimonial drugs has increased. Hence, in the present study Leishmania major isolates were collected from patients with resistance phenotype and the presence/absence of resistance to Glucantime was investigated. MATERIALS AND METHODS: Samples were taken from 10 cutaneous leishmaniasis (CL) patients who had not responded to chemotherapy with Glucantime. Nested polymerase chain reaction (PCR) was performed to identify the isolated species. Stationary phase promastigotes were added to the grown, adhesive J774 macrophages. Values obtained from standard strain were compared with the test cultures after exposure to the medicine. In vivo, the effects of Glucantime were assessed by comparing the sizes and the parasite burden of the lesions on mouse model. RESULTS: The results of amplified band on agarose gel demonstrated all samples were L. major. After exposure to medicine, a reduction of intracellular amastigotes to half was detected. In vivo, the parasite was eliminated in 90% of mice with lesions caused by both isolates of patients and standard L. major, and their lesions became smaller significantly. CONCLUSION: Pentavalent antimonial (SbV) salts are the main component of chemotherapy against leishmaniasis. However, the medicine has been found ineffective. In the present study, isolates from patients with no response to treatment had no significant difference from the standard L. major strain (as the sensitive strain). Therefore, in patients with resistance phenotype to Glucantime, the parasites did not actually have intrinsic resistance, i.e., environmental and host factors prevented the successful treatment of the disease.