Investigation of drug resistance in canine leishmaniasis and leishmania tropica

Objective: Leishmaniasis is endemic in 98 countries, poses risk to almost one billion people in the world. The infection caused by obligatory intracellular parasite Leishmania spp. in dogs is called Canine Leishmanisis (CanL). In this study, it was aimed to detect the resistance status of Leishmania tropica strains isolated from dogs in our country against amphotericin B, meglumine antimonate and sodium stibogluconate applied in leishmaniasis treatment. Material and Methods: Leishmania spp. promastigotes, removed from liquid nitrogen were first cultured in NNN media, then the growing isolates were transferred to RPMI-1640 medium and abundant amount of promastigotes were obtained. Isolates were genotyped using the real-time polymerase chain reaction method with primers and probes specific to the ITS-1 region of Leishmania spp. Amphotericin B, meglumine antimonate and sodium stibogluconate resistance status were investigated by hemocytometer and XTT methods in five isolates that were found to be L. tropica causing CanL. Results: The mean IC50 values were determined as 10.60 mg/ml for meglumine antimonate, 0.1471 mg/ml for sodium stibogluconate, 0.0328 µM/ml for amphotericin B by hemocytometer method. Mean IC50 values determined by XTT method were 10.48 mg/ml for meglumine antimonate, 0.1470 mg/ml for sodium stibogluconate, 0.0326 µM/ml for amphotericin B. Conclusions: According to our data, while L. tropica strains which were isolated from CanL cases and rare in dogs, were not found to be resistant to amphoreticin B and sodium stibogluconate, it was observed that parasite developed drug resistance against meglumine antimonate. In the future, this situation is thought to be a problem during treatment in human cutaneous leishmaniasis cases.