Purpureocillium lilacinum an emergent pathogen: antifungal susceptibility of environmental and clinical strains.

Purpureocillium lilacinum is a filamentous and hyaline fungus cosmopolitan, saprophytic, largely used in the biological control of plant-parasitic nematodes and insects, also considered an emerging and opportunistic human pathogen. The standard treatment for hyalohyphomycosis caused by P. lilacinum is not yet defined, since this fungus is resistant to different antifungals, in vitro and in vivo. The aim of this study was to evaluate and compare in vitro antifungal activity against environmental and clinical P. lilacinum isolates and our results demonstrated that these isolates can be resistant to newer generation triazoles, such as voriconazole, and to caspofungin, a drug of the echinocandin class. In summary, we highlight the importance of knowing the different susceptibility profiles of P. lilacinum isolates, and besides that, the emergence of uncommon human and animal opportunistic fungi, such P. lilacinum, especially during COVID-19, highlight the need for antifungal susceptibility testing of isolates since empirical therapy with different treatment schedules failed in great number of patients.

Multicenter, International Study of MIC/MEC Distributions for Definition of Epidemiological Cutoff Values for Sporothrix Species Identified by Molecular Methods.

Clinical and Laboratory Standards Institute (CLSI) conditions for testing the susceptibilities of pathogenic Sporothrix species to antifungal agents are based on a collaborative study that evaluated five clinically relevant isolates of Sporothrixschenckii sensu lato and some antifungal agents. With the advent of molecular identification, there are two basic needs: to confirm the suitability of these testing conditions for all agents and Sporothrix species and to establish species-specific epidemiologic cutoff values (ECVs) or breakpoints (BPs) for the species. We collected available CLSI MICs/minimal effective concentrations (MECs) of amphotericin B, five triazoles, terbinafine, flucytosine, and caspofungin for 301 Sporothrix schenckii sensu stricto, 486 S. brasiliensis, 75 S. globosa, and 13 S. mexicana molecularly identified isolates. Data were obtained in 17 independent laboratories (Australia, Europe, India, South Africa, and South and North America) using conidial inoculum suspensions and 48 to 72 h of incubation at 35°C. Sufficient and suitable data (modal MICs within 2-fold concentrations) allowed the proposal of the following ECVs for S. schenckii and S. brasiliensis, respectively: amphotericin B, 4 and 4 µg/ml; itraconazole, 2 and 2 µg/ml; posaconazole, 2 and 2 µg/ml; and voriconazole, 64 and 32 µg/ml. Ketoconazole and terbinafine ECVs for S. brasiliensis were 2 and 0.12 µg/ml, respectively. Insufficient or unsuitable data precluded the calculation of ketoconazole and terbinafine (or any other antifungal agent) ECVs for S. schenckii, as well as ECVs for S. globosa and S. mexicana These ECVs could aid the clinician in identifying potentially resistant isolates (non-wild type) less likely to respond to therapy.