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Summary Cryptococcus albidus and Cryptococcus laurentii are uncommon species of this genus that in recent decades have increasingly caused opportunistic infections in humans, mainly in immunocompromised patients; the best therapy for such infection being unknown. Using a murine model of systemic infection by these fungi, we have evaluated the efficacy of amphotericin B (AMB) at 0.8 mg/kg, administered intravenously, fluconazole (FLC) or voriconazole (VRC), both administered orally, at 25 mg/kg and the combination of AMB plus VRC against three C. albidus and two C. laurentii strains. All the treatments significantly reduced the fungal burden in all the organs studied. The combination showed a synergistic effect in the reduction in fungal load, working better than both monotherapies. The histopathological study confirmed the efficacy of the treatments.

Candida kefyr is an emerging pathogen able to cause disseminated infection, especially in immunocompromised patients. Although guidelines for the treatment of invasive candidiasis have been published, no specific recommendations against C. kefyr are available. We determine the in vitro killing activity of amphotericin B (AMB), fluconazole (FLC) and caspofungin (CFG) as well as their efficacy in a murine model of systemic infection by two C. kefyr strains. Time-kill curves of AMB, FLC and CFG were determined in final volumes of 10 ml containing the assayed drugs ranged from 0.03 to 32 μg ml-1 at different time points and efficacy of the drugs was evaluated in a systemic model of candidiasis, conducted in immunosuppressed mice, through survival, (1→3)-β-D-glucan levels in serum and fungal load in kidneys. AMB and CFG showed fungicidal and FLC fungistatic activity against both isolates. The three drugs were able to reduce fungal burden in kidneys and (1→3)-β-D-glucan concentration in serum of infected mice, with CFG showing the highest efficacy, followed by FLC. In conclusion, CFG showed efficacy over AMB and FLC against the systemic candidiasis by C. kefyr. The established epidemiological cut-off for anidulafungin seems the best indicator of outcome for echinocandins.

Summary The efficacy of voriconazole (VRC) was evaluated against two strains of each of the two most common species causing sporotrichosis, Sporothrix schenckii sensu stricto and Sporothrix brasiliensis, using a murine model of disseminated infection. Voriconazole was administered at doses of 20 or 40 mg kg−1 per day by gavage. The drug showed some efficacy, especially at 40 mg kg−1 per day, in prolonging the survival and reducing fungal load in spleen and liver in mice infected with S. schenckii, whereas in animals infected with S. brasiliensis the drug did not work.

Summary We have evaluated the virulence of two clinically relevant species of Curvularia; Curvularia spicifera and C. hawaiiensis, using an experimental model of disseminated infection in immunocompromised mice. Several inocula were tested over a range 1 × 103–1 × 106 colony-forming units/animal. Both species had a similar behaviour, producing a high mortality. Tissue burden and histopathology studies demonstrated that lung was the organ most affected.