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 Sporothrix schenckii 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 /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.A. Espinel-Ingroff, D. P. B. Abreu, R. Almeida-Paes, R. S. N. Brilhante, A. Chakrabarti, A. Chowdhary, F. Hagen, S. Córdoba, G. M. Gonzalez, N. P. Govender, J. Guarro, E. M. Johnson, S. E. Kidd, S. A. Pereira, A. M. Rodrigues, S. Rozental, M. W. Szeszs, R. Ballesté Alaniz, A. Bonifaz, L. X. Bonfietti, L. P. Borba-Santos, J. Capilla, A. L. Colombo, M. Dolande, M. G. Isla, M. S. C. Melhem, A. C. Mesa-Arango, M. M. E. Oliveira, M. M. Panizo, Z. Pires de Camargo, R. M. Zancope-Oliveira, J. F. Meis, J. Turnidge

MDGC-MS analysis of essential oils from Protium heptaphyllum (Aubl.) and their antifungal activity against Candida specie

ABSTRACT Protium heptaphyllum is found in the Amazon region, and in various Brazilian states and South American countries. Also Known as almecega, it produces an oil resin used in traditional medicine as analgesic, anti-inflammatory, cicatrizant and expectorant, it is rich in pentacyclic triterpenes and essential oil. The main objective of this study was to analyze the chemical composition of P. heptaphyllumresin (OEPh) over different extraction times and to evaluate their antifungal activity against Candida species, obtained from gardeners with onychomycosis, using the disk diffusion method. The OEPh was obtained by hydrodistillation and analyzed by Multidimensional Gas Chromatography coupled with Mass Spectrometry (MDGC / MS). Candida species were obtained from lesions on the nails of horticulturist from a community garden in the city of Teresina, Piauí, Brazil. The antifungal activity in concentrations of 1000 µg/L, 500 µg/L and 250 µg/L, PROTOCOL M44-A2 (CLSI 2009) OEPh was tested. The main constituents identified were: l-limonene, α-terpineol, p-cineol, o-cymene and α-phellandrene, however, its composition varies significantly with extraction time. All species, except C. rugosa, were inhibited with halo (≥ 14 mm) at 1000 μg / L. C. krusei is naturally resistant to the drug fluconazole, but when tested with OEPh the clinical species (case 9) demonstrated sensitivity in three dilutions (halo ≤ 10 ≥ 14) and the standard strain was inhibited at concentration of 1000 μg/Lg / L (halo 14mm). A similar situation also occurred with the standard strain of C. parapsilosis (halo ≥ 11mm). OEPh has considerable antifungal activity, which merits further investigation for alternative clinical applications, since this species is widely distributed in our community, and it presents good yields, and also has important therapeutic applications

Multilaboratory study of epidemiological cutoff values for detection of resistance in eight Candida species to fluconazole, posaconazole, and voriconazole

Contains fulltext : 137491.pdf (publisher's version ) (Open Access)Although epidemiological cutoff values (ECVs) have been established for Candida spp. and the triazoles, they are based on MIC data from a single laboratory. We have established ECVs for eight Candida species and fluconazole, posaconazole, and voriconazole based on wild-type (WT) MIC distributions for isolates of C. albicans (n=11,241 isolates), C. glabrata (7,538), C. parapsilosis (6,023), C. tropicalis (3,748), C. krusei (1,073), C. lusitaniae (574), C. guilliermondii (373), and C. dubliniensis (162). The 24-h CLSI broth microdilution MICs were collated from multiple laboratories (in Canada, Brazil, Europe, Mexico, Peru, and the United States). The ECVs for distributions originating from >/=6 laboratories, which included >/=95% of the modeled WT population, for fluconazole, posaconazole, and voriconazole were, respectively, 0.5, 0.06 and 0.03 mug/ml for C. albicans, 0.5, 0.25, and 0.03 mug/ml for C. dubliniensis, 8, 1, and 0.25 mug/ml for C. glabrata, 8, 0.5, and 0.12 mug/ml for C. guilliermondii, 32, 0.5, and 0.25 mug/ml for C. krusei, 1, 0.06, and 0.06 mug/ml for C. lusitaniae, 1, 0.25, and 0.03 mug/ml for C. parapsilosis, and 1, 0.12, and 0.06 mug/ml for C. tropicalis. The low number of MICs (<100) for other less prevalent species (C. famata, C. kefyr, C. orthopsilosis, C. rugosa) precluded ECV definition, but their MIC distributions are documented. Evaluation of our ECVs for some species/agent combinations using published individual MICs for 136 isolates (harboring mutations in or upregulation of ERG11, MDR1, CDR1, or CDR2) and 64 WT isolates indicated that our ECVs may be useful in distinguishing WT from non-WT isolates

International Evaluation of MIC Distributions and Epidemiological Cutoff Value (ECV) Definitions for Fusarium Species Identified by Molecular Methods for the CLSI Broth Microdilution Method.

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