Evaluation of virulence and drug resistance of Sporothrix globosa itraconazole-resistant strains in Galleria mellonella

Abstract

Objective: To evaluate virulence of itraconazole-resistant Sporothrix globosa and its sensitivity to itraconazole in Galleria mellonella. Methods: Itraconazole-resistant strain and itraconazole-sensitive strain of S. globosa were used to infect the Galleria mellonella larvae. Change in appearance, body feedback and survival of the larva were observed. Itraconazole was injected into the infected larvae at a dose of 20 mg/kg and 40 mg/kg, respectively. The survival and fungal burden of the larva were observed. Results: At the end of observation, there was no statistical difference in the survival curve between the resistant-strain group and sensitive-strain group (χ2=2.37, P=0.124). After injecting itraconazole at 40 mg/kg, the survival rates of itraconazole-resistant strain and itraconazole-sensitive strain increased by 40% and 60%, respectively, and there was no statistical difference between them (χ2=1.20, P=0.466).The colony count of CBS120340 was significantly lower than that of SUMS0381(t=-18.64, P<0.001). Conclusion: In Galleria mellonella, there was no difference in virulence between itraconazole-resistant strain and itraconazole-sensitive strain of S. globosa, and itraconazole-resistant strain showed lower sensitivity to itraconazole.

Keywords

• s. globosa
• galleria mellonella
• virulence
• itraconazole