Mariana I D S Xisto1,2, Rita D F Caramalho1, Débora A S Rocha3, Antonio Ferreira-Pereira3, Bettina Sartori1, Eliana Barreto-Bergter2, Maria L Junqueira4, Cornelia Lass-Flörl1, Michaela Lackner1. 1. Division of Hygiene and Medical Microbiology, Innsbruck Medical University, Innsbruck, Austria. 2. Laboratório de Química Biológica de Microorganismos, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. 3. Laboratório de Bioquímica Microbiana, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil. 4. Hospital Universitário, Universidade Federal de Juiz de Fora, Minas Gerais, Brazil.
Abstract
Objectives: Candidaemia is a public health problem mainly in hospitalized individuals worldwide. In Brazil, Candida albicans is the most prevalent species that causes candidaemia, followed by Candida tropicalis and Candida parapsilosis . Few data on the abundance of antifungal resistance are available for Latin America. Methods: We analysed the frequency of azole and echinocandin resistance in Candida isolates ( n = 75) collected between 2012 and 2014 at the University Hospital of Federal University of Juiz de Fora (Brazil). The primary targets erg11 (azoles) and fks1 (echinocandins) were sequenced and modelled at the protein level. Antifungal susceptibility testing was performed according to CLSI (M27-A3 and M27-S4) and according to EUCAST. Results: The three most frequent species were C. albicans (38.0%), C. tropicalis (30.0%) and Candida glabrata (17.0%). Azole resistance was observed in 27.0% of all Candida isolates, while 20.0% of all isolates were echinocandin resistant. A novel mutation in erg11 at location K143R was found to be associated with phenotypically pan-azole-resistant C. tropicalis isolates. This mutation maps near the active binding site of erg11 and is likely to confer pan-azole resistance to C. tropicalis . Conclusions: A novel point mutation (K143R) located in the erg11 gene of C. tropicalis was found in pan-azole-resistant strains. According to our protein homology model, it is very likely that the mutation K143R causes pan-azole resistance in C. tropicalis . Moreover, an up-regulation of ABC transporters was observed, which can add up to a pan-azole-resistant phenotype.
Objectives: Candidaemia is a public health problem mainly in hospitalized individuals worldwide. In Brazil, Candida albicans is the most prevalent species that causes candidaemia, followed by Candida tropicalis and Candida parapsilosis . Few data on the abundance of antifungal resistance are available for Latin America. Methods: We analysed the frequency of azole and echinocandin resistance in Candida isolates ( n = 75) collected between 2012 and 2014 at the University Hospital of Federal University of Juiz de Fora (Brazil). The primary targets erg11 (azoles) and fks1 (echinocandins) were sequenced and modelled at the protein level. Antifungal susceptibility testing was performed according to CLSI (M27-A3 and M27-S4) and according to EUCAST. Results: The three most frequent species were C. albicans (38.0%), C. tropicalis (30.0%) and Candida glabrata (17.0%). Azole resistance was observed in 27.0% of all Candida isolates, while 20.0% of all isolates were echinocandin resistant. A novel mutation in erg11 at location K143R was found to be associated with phenotypically pan-azole-resistant C. tropicalis isolates. This mutation maps near the active binding site of erg11 and is likely to confer pan-azole resistance to C. tropicalis . Conclusions: A novel point mutation (K143R) located in the erg11 gene of C. tropicalis was found in pan-azole-resistant strains. According to our protein homology model, it is very likely that the mutation K143R causes pan-azole resistance in C. tropicalis . Moreover, an up-regulation of ABC transporters was observed, which can add up to a pan-azole-resistant phenotype.
Authors: Michael A Pfaller; Daniel J Diekema; John D Turnidge; Mariana Castanheira; Ronald N Jones Journal: Open Forum Infect Dis Date: 2019-03-15 Impact factor: 3.835
Authors: A Espinel-Ingroff; M Sasso; J Turnidge; M Arendrup; F Botterel; N Bourgeois; B Bouteille; E Canton; S Cassaing; E Dannaoui; M Dehais; L Delhaes; D Dupont; A Fekkar; J Fuller; G Garcia-Effron; J Garcia; G M Gonzalez; N P Govender; H Guegan; J Guinea; S Houzé; C Lass-Flörl; T Pelaez; A Forastiero; M Lackner; R Magobo Journal: Antimicrob Agents Chemother Date: 2021-08-09 Impact factor: 5.191