Efficacy of echinocandins against murine infections by Diutina (Candida) rugosa

• The in vitro activity and the in vivo efficacy of anidulafungin and caspofungin against two isolates of Diutina rugosa showing the commonest minimal inhibitory concentrations of both drugs were evaluated.
• Time-killing curves showed fungicidal concentration-dependent activity against both isolates.
• Anidulafungin and caspofungin showed in vivo efficacy being the higher doses the most effectives.
• Both drugs showed efficacy but further studies including strains showing wide minimal inhibitory concentrations range are necessary to corroborate our results.

Echinocandins are recommended as a first-line therapy for invasive candidiasis. Candida rugosa was recently transferred to the new genus Diutina. We have determined the in vitro killing kinetics of two echinocandins, anidulafungin, and caspofungin and their in vivo efficacy, administering doses of 5 or 10 mg/kg, and 1 or 5 mg/kg, respectively against 2 clinical strains of D. rugosa. Both drugs showed a fungicidal concentration-dependent activity and, in a neutropenic murine model of disseminated infection, were able to reduce tissue burden and to prolong survival of mice. These results suggest that both echinocandins could be useful to treat infections by this fungus when isolates show minimal inhibitory concentrations within the range of susceptibility for both drugs.