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Background: Studies comparing gradient diffusion strips (GDSs) and the EUCAST E.Def 9.4 microdilution method are scarce, thwarted by a low number of isolates, and restricted to selected antifungal agents. Objectives: We evaluated the performance of GDSs to detect azole resistance in A. fumigatus, including cryptic species. Patients/Methods: A. fumigatus sensu stricto (n = 89) and cryptic species (n = 52) were classified as susceptible or resistant to itraconazole, voriconazole, posaconazole and isavuconazole (EUCAST E.Def 9.4; clinical breakpoints v10). A. fumigatus sensu stricto azole‐resistant isolates had the following cyp51A gene mutations: TR34‐L98H (n = 24), G54R (n = 5), TR46‐Y121F‐T289A (n = 1), F46Y‐M172V‐N248T‐D255E‐E427K (n = 1), F165L (n = 1) and cyp51A gene wild type (n = 3). GDSs (ETEST®, bioMèrieux, Marcy‐l'Etoile, France and Liofilchem®, Roseto degli Abruzzi, Italy) MICs were obtained by following the manufacturer's guidelines. Results: For A. fumigatus sensu stricto, itraconazole MICs >1.5 mg/L, voriconazole >0.38 mg/L, posaconazole >0.75 mg/L, and isavuconazole >0.5 mg/L correctly separated resistant from susceptible isolates with two exceptions. Considering the aforementioned cut‐off MICs, sensitivity/specificity values of GDSs to detect azole resistance were: itraconazole (97%/100%), voriconazole (97%/100%), posaconazole (97%/100%) and isavuconazole (93.3%/100%). For cryptic species isolates, voriconazole MICs >1 mg/L and isavuconazole >0.75 mg/L separated resistant isolates from susceptible isolates with 15 and 27 exceptions, respectively. Considering the aforementioned cut‐off MICs, sensitivity/specificity values were as follows: voriconazole (68.1%/100%) and isavuconazole (25%/100%). For itraconazole and posaconazole, it was not possible to establish cut‐off values. Conclusions: We set tentative cut‐off MIC values to correctly spot resistant Aspergillus fumigatus sensu stricto isolates using GDSs. The performance against cryptic species was poor. [ABSTRACT FROM AUTHOR]

We evaluated the combined performance of itraconazole and voriconazole Etest® gradient concentration strips for the detection of Aspergillus fumigatus azole resistance associated with cyp51a mutations confirmed by gene sequencing. Among 118 A. fumigatus clinical isolates collected in a French center, 6 (5%) had azole resistance mutations, 5 of which were probably of environmental origin. Using recent method-dependent epidemiological cutoff values as thresholds, the combination's sensitivity and specificity were 100% [95% confidence interval 61-100] and 99% [95-100]. Our results support itraconazole and voriconazole Etest® combined use as a promising self-sufficient method for simple, efficient and reliable cyp51a-related azole-resistant A. fumigatus detection., (© The Author(s) 2024. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology.)

In vitro susceptibility tests to antifungals have become a current need, since they offer the possibility to select the most appropriate drug. In order to determine the in vitro sensitivity to fluconazole and voriconazole in Candida spp. isolates from 325 patients with Human Immunodeficiency Virus infection in Ciudad Bolivar, Venezuela, a prospective study was conducted in two hospitals. Samples of oral mucosa were taken and inoculated in Sabouraud dextrose chloramphenicol agar plates. Yeast species were identified by direct biochemical tests, chromogenic media system and Api 20C y 32C (BioMerieux, France®). In vitro susceptibility was performed by agar diffusion (M44-A2). Candida species were isolated in 215 subjects (66.2%). The isolated species were Candida albicans (n = 164; 76.3%), C. parapsilosis Complex (n = 30; 13.9%), Pichia kudriavzevii (C. krusei) (n = 20; 9.3%) and C. tropicalis (n = 1; 0.5%). A 65.2% of C. albicans isolates were sensitive to fluconazole (n = 107), 32.3% were resistant (n = 53) and 2.4% (n = 4) dose-dependent susceptible. Resistance to both antifungals was showed by P. kudriavzevii. Most of the isolates were susceptible to voriconazole (n = 153; 71.1%): only 19.5% of C. albicans was resistant to this antifungal. It is shown that C. albicans was the prevalent pathogen isolated from oral mucosal samples of HIV-infected patients, and showed a variable sensitivity to fluconazol and good sensitivity to voriconazole, constituting a therapeutic alternative to consider in cases of resistance. [ABSTRACT FROM AUTHOR]

Resistance of Aspergillus fumigatus to triazoles has been reported increasingly in Europe. As few data are available from Southern France, the objectives of this study were to assess the burden of A. fumigatus isolates with azole resistance from clinical specimens in Lyon, and explore the resistance mechanisms involved. In this retrospective cross-sectional study, 221 consecutive A. fumigatus isolates from respiratory samples were identified from an 8-month period from 195 patients attending the Pulmonary Medicine Departments of Lyon University Hospitals. Morphological identification was confirmed by sequence analysis of the β-tubulin gene. All samples were tested for susceptibilities to itraconazole, voriconazole, posaconazole and isavuconazole using concentration gradient strips, and the results were confirmed using the EUCAST broth microdilution method. Resistance mechanisms were investigated by sequencing the cyp51A gene and its promoter, and by expression analysis of cyp51 and genes encoding several efflux transporters. Four isolates exhibited azole resistance. Three isolates presented with polymorphisms in an intronic region of cyp51A, and one isolate had F46Y, M172V and E427K polymorphisms. No mutations were identified in the cyp51A promoter, but significant induction of cyp51A and cyp51B gene expression was observed for all four and three isolates, respectively. Significant induction of atrF and cdr1B gene expression was observed for two and three isolates, respectively. No significant induction of MDR1/2/3/4, MFS56 and M85 gene expression was observed. To conclude, the observed prevalence of azole resistance was 2.1%. Significant induction of expression of the cyp51 genes and two genes encoding efflux transporters was evidenced, underlying the diversity of resistance mechanisms to be explored., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objectives: Recent studies have reported the emerging worldwide problem of azole drug resistance of A. fumigatus isolates. The aim of this study was to evaluate the antifungal susceptibilities of A. fumigatus isolates recovered from air and clinical samples collected in a French University hospital (Lyon), which underwent major deconstruction works over a one year-period., Methods: A daily surveillance of fungal contamination was implemented during 11-months. Environmental survey was realized by air samplings, outdoor and indoor, with an automatic agar sampler. In parallel, surveillance of IA infection cases was conducted by epidemiological investigation. Environmental and clinical isolates of A. fumigatus were identified by conventional methods and β-tubulin sequencing. Susceptibility testing of A. fumigatus isolates against Itraconazole (ITZ), Voriconazole (VCZ) was performed using Etest method., Results: A total of 3885 air samples (1744 outdoor samples and 2141 indoor samples) were collected. From the 3073 identified colonies of A. fumigatus, 400 A. fumigatus isolates were tested for their susceptibility to ITZ and VCZ, including 388 isolates coming from the environment (indoor n:157, outdoor n:231) and 12 isolates coming from clinical samples. All the 400 isolates were susceptible to azoles (≤1μg/mL)., Conclusions: No environmental reservoir of A. fumigatus azole resistant strains was found in our hospital which was undergoing major demolition works. Further studies with larger number of A. fumigatus clinical isolates and environmental isolates from agricultural areas and healthcare establishments are needed to better appreciate the occurrence and prevalence of azole resistance., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

Introduction: Monitoring fungal aerocontamination is an essential measure to prevent severe invasive aspergillosis (IA) infections in hospitals. One central block among 32 blocks of Edouard Herriot Hospital (EHH) was entirely demolished in 2015, while care activities continued in surrounding blocks. The main objective was to undertake broad environmental monitoring and clinical surveillance of IA cases to document fungal dispersion during major deconstruction work and to assess clinical risk., Methods and Analysis: A daily environmental survey of fungal loads was conducted in eight wards located near the demolition site. Air was collected inside and outside selected wards by agar impact samplers. Daily spore concentrations were monitored continuously by volumetric samplers at a flow rate of 10 L.min -1 . Daily temperature, wind direction and speed as well as relative humidity were recorded by the French meteorological station Meteociel. Aspergillus fumigatus strains stored will be genotyped by multiple-locus, variable-number, tandem-repeat analysis. Antifungal susceptibility will be assessed by E-test strips on Roswell Park Memorial Institute medium supplemented with agar. Ascertaining the adequacy of current environmental monitoring techniques in hospital is of growing importance, considering the rising impact of fungal infections and of curative antifungal costs. The present study could improve the daily management of IA risk during major deconstruction work and generate new data to ameliorate and redefine current guidelines., Ethics and Dissemination: This study was approved by the clinical research and ethics committees of EHH., Competing Interests: Competing interests: All authors approved the final version of the manuscript and vouch that it is not being considered for publication elsewhere., (© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Objectives: Several studies, especially in Europe, have recently reported the emerging phenomenon of azole resistance in Aspergillus fumigatus, but very few data are available in France. Our study aimed to determine the resistance prevalence in A. fumigatus isolates recovered from clinical samples over a 1-year period in two university hospital centers., Methods: All A. fumigatus isolates were screened for azole resistance using RPMI agar plates supplemented with itraconazole and voriconazole. Resistance was then confirmed by the EUCAST method. A part of the beta-tubulin gene was amplified for resistant isolates to confirm the A. fumigatus species, and the Cyp51A gene and its promoter were afterward sequenced to detect mutations potentially responsible for this resistance., Results: One hundred sixty-five A. fumigatus isolates were recovered from 134 patients. Three isolates recovered from three patients were found resistant with MICs of >8 mg/l, 4 mg/l, and 1 mg/l for itraconazole, voriconazole, and posaconazole, respectively. The TR34/L98H mutation, previously and largely described in other countries, was detected in the three isolates., Conclusion: Our study demonstrated the occurrence of azole resistance among unselected A. fumigatus clinical isolates, with an overall prevalence of 1.8%., (© The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)