Background & objectives: Insufficient treatment of cutaneous leishmaniasis (CL) by conventional drugs is a major barrier in control strategies. This study was aimed to evaluate Glucantime efficacy and the susceptibility of Glucantime unresponsive and responsive CL isolates in the field and laboratory.
Methods: Chi-square test (x[2]) was used to determine the significance of difference between proportions in Glucantime-treated patients. The inhibitory activity of various concentrations of Glucantime against Leishmenia tropica stages was evaluated by a colorimetric cell viability MTT and macrophage assays. Mixed model, t-test and ANOVA were performed to determine the significance of difference between various concentrations of Glucantime unresponsive or responsive isolates and untreated control group and p <0.05 was defined as significant level. Altogether, 89.8% of the patients were cured by Glucantime, whilst 10.2% remained non-cured.
Results: The overall Glucantime efficacy in different age groups and genders was similar. The IC50 values of promastigotes and amastigotes for Glucanime unresponsive isolates were 2.1 and 2.6 times higher than the equivalent rates obtained for responsive cases, respectively. The overall mean number of amastigotes within macrophages in unresponsive isolates was significantly higher (32.68 ± 1.24) than that in responsive ones (18.68 ± 1.52, p <0.001). Glucantime unresponsive and responsive field isolates of anthroponotic CL (ACL) caused by L. tropica strongly correlated to in vitro assays.
Interpretation & conclusion: Monitoring of Glucantime unresponsiveness by the health surveillance system is extremely important, where anthroponotic transmission occurs in humans. Hence, physicians should be aware of such clinical unresponsive presentations with ACL for antimonial therapeutic failure to improve management of disease in endemic regions.
Keywords: Cutaneous leishmaniasis; Glucantime unresponsiveness; in vitro evaluation.