In vitro activities of 15 antifungal drugs against a large collection of clinical isolates of Microsporum canis

Background Microsporum canis is a zoophilic species, found to be the most frequently isolated species in animals. M. canis causes sporadic outbreaks of infections in humans, such as the one that occurred in Canada, where more than 1000 human cases were detected over an 8-year period. Despite the medical importance of M. canis infections, there are limited in vitro data on the antifungal susceptibility to antifungal drugs, including new generation triazoles and imidazoles. Objective The aim of the current study was to comprehensively evaluate the in vitro activity of new azoles and comparator drugs against a large panel of M. canis isolates using a microdilution assay. Methods The in vitro susceptibility to novel triazoles and imidazoles was compared to that of other antifungal drugs using a large collection of M. canis clinical isolates (n = 208) obtained from patients and animals with dermatophytosis in Iran, France and Turkey. Results All isolates exhibited high susceptibility to the majority of the tested antifungal agents. However, luliconazole, lanoconazole and efinaconazole, as well as econazole, demonstrated superior activity against all strains in comparis on with the other drugs. Conclusion FDA-approved antifungal drugs, that is luliconazole, efinaconazole and lanoconazole, showed the highest antifungal activity and should be promising candidates for the treatment of dermatophytosis caused by M canis. However, their therapeutic effectiveness remains to be determined in clinical settings.