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Ghorbel D, Amouri I, Khemekhem N, Neji S, Trabelsi H, Elloumi M, Sellami H, Makni F, Ayadi A, Hadrich I. Investigation of Azole Resistance Involving cyp51A and cyp51B Genes in Clinical Aspergillus flavus Isolates. Pol J Microbiol 2024; 73:131-142. [PMID: 38700908 PMCID: PMC11192525 DOI: 10.33073/pjm-2024-001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 12/03/2023] [Indexed: 06/22/2024] Open
Abstract
This study aimed to investigate azole resistance mechanisms in Aspergillus flavus, which involve cyp51A and cyp51B genes. Real-time Reverse Transcriptase qPCR method was applied to determine the overexpression of cyp51A and cyp51B genes for 34 A. flavus isolates. PCR sequencing of these two genes was used to detect the presence of gene mutations. Susceptibility test found sensitivity to voriconazole (VOR) in all strains. 14.7% and 8.8% of isolates were resistant to itraconazole (IT) and posaconazole (POS), respectively, with a cross-resistance in 5.8%. For the double resistant isolates (IT/POS), the expression of cyp51A was up to 17-fold higher. PCR sequencing showed the presence of 2 mutations in cyp51A: a synonymous point mutation (P61P) in eight isolates, which did not affect the structure of CYP51A protein, and another non synonymous mutation (G206L) for only the TN-33 strain (cross IT/POS resistance) causing an amino acid change in the protein sequence. However, we noted in cyp51B the presence of the only non-synonymous mutation (L177G) causing a change in amino acids in the protein sequence for the TN-31 strain, which exhibits IT/POS cross-resistance. A short single intron of 67 bp was identified in the cyp51A gene, whereas three short introns of 54, 53, and 160 bp were identified in the cyp51B gene. According to the models provided by PatchDock software, the presence of non-synonymous mutations did not affect the interaction of CYP51A and CYP51B proteins with antifungals. In our study, the overexpression of the cyp51A and cyp51B genes is the primary mechanism responsible for resistance in A. flavus collection. Nevertheless, other resistance mechanisms can be involved.
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Affiliation(s)
- Dhoha Ghorbel
- 1Fungi and Parasitic Molecular Biology Laboratory, School of Medicine, University of Sfax, Sfax, Tunisia
| | - Imen Amouri
- 1Fungi and Parasitic Molecular Biology Laboratory, School of Medicine, University of Sfax, Sfax, Tunisia
| | - Nahed Khemekhem
- 1Fungi and Parasitic Molecular Biology Laboratory, School of Medicine, University of Sfax, Sfax, Tunisia
| | - Sourour Neji
- 1Fungi and Parasitic Molecular Biology Laboratory, School of Medicine, University of Sfax, Sfax, Tunisia
| | - Houaida Trabelsi
- 1Fungi and Parasitic Molecular Biology Laboratory, School of Medicine, University of Sfax, Sfax, Tunisia
| | - Moez Elloumi
- 3Haematology Department, UH Hedi Chaker, Sfax, Tunisia
| | - Hayet Sellami
- 1Fungi and Parasitic Molecular Biology Laboratory, School of Medicine, University of Sfax, Sfax, Tunisia
| | - Fattouma Makni
- 1Fungi and Parasitic Molecular Biology Laboratory, School of Medicine, University of Sfax, Sfax, Tunisia
| | - Ali Ayadi
- 1Fungi and Parasitic Molecular Biology Laboratory, School of Medicine, University of Sfax, Sfax, Tunisia
| | - Ines Hadrich
- 1Fungi and Parasitic Molecular Biology Laboratory, School of Medicine, University of Sfax, Sfax, Tunisia
- 2Faculty of Science, University of Gabes, Gabes, Tunisia
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2
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Schürch S, Gindro K, Schnee S, Dubuis PH, Codina JM, Wilhelm M, Riat A, Lamoth F, Sanglard D. Occurrence of Aspergillus fumigatus azole resistance in soils from Switzerland. Med Mycol 2023; 61:myad110. [PMID: 37930839 PMCID: PMC10653585 DOI: 10.1093/mmy/myad110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 10/17/2023] [Accepted: 10/31/2023] [Indexed: 11/08/2023] Open
Abstract
Aspergillus fumigatus is a fungal species causing diverse diseases in humans. The use of azoles for treatments of A. fumigatus diseases has resulted in azole resistance. Azoles are also widely used in the environment for crop protection, which resulted in azole resistance. Resistance is primarily due to mutations in cyp51A, which encodes the target protein for azoles. Here we addressed the occurrence of azole resistance in soils from a vast part of Switzerland. We aimed to associate the use of azoles in the environment with the occurrence of azole resistance. We targeted sample sites from different agricultural environments as well as sites with no agricultural practice (natural sites and urban sites). Starting from 327 sites, 113 A. fumigatus isolates were recovered (2019-2021), among which 19 were azole-resistant (15 with TR34/L98H and four with TR46/Y121F/T289A resistance mutations in cyp51A). Our results show that azole resistance was not associated with a specific agricultural practice. Azoles could be chemically detected in investigated soils, however, their presence was not associated with the occurrence of azole-resistant isolates. Interestingly, genetic markers of resistance to other fungicides were detected but only in azole-resistant isolates, thus reinforcing the notion that A. fumigatus cross-resistance to fungicides has an environmental origin. In conclusion, this study reveals the spreading of azole resistance in A. fumigatus from the environment in Switzerland. The proximity of agricultural areas to urban centers may facilitate the transmission of resistant strains to at-risk populations. Thus, vigilant surveillance is required to maintain effective treatment options for aspergillosis.
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Affiliation(s)
- Stéphanie Schürch
- Plant Protection Research Division, Mycology Group, Agroscope, 1260 Nyon, Switzerland
| | - Katia Gindro
- Plant Protection Research Division, Mycology Group, Agroscope, 1260 Nyon, Switzerland
| | - Sylvain Schnee
- Plant Protection Research Division, Mycology Group, Agroscope, 1260 Nyon, Switzerland
| | - Pierre-Henri Dubuis
- Plant Protection Research Division, Mycology Group, Agroscope, 1260 Nyon, Switzerland
| | - Josep Massana Codina
- Plant Protection Research Division, Mycology Group, Agroscope, 1260 Nyon, Switzerland
| | - Matthieu Wilhelm
- Plant Protection Research Division, Mycology Group, Agroscope, 1260 Nyon, Switzerland
| | - Arnaud Riat
- Service of Infectious Diseases and Service of Laboratory Medicine, Geneva University Hospitals and Geneva University, 1205 Geneva, Switzerland
| | - Frédéric Lamoth
- Infectious Diseases Service, Department of Medicine, Lausanne University Hospital and University of Lausanne, 1011 Lausanne, Switzerland
- Institute of Microbiology, Lausanne University Hospital and University of Lausanne, 1011 Lausanne, Switzerland
| | - Dominique Sanglard
- Institute of Microbiology, Lausanne University Hospital and University of Lausanne, 1011 Lausanne, Switzerland
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da Fonseca LMM, Braga VF, Tonani L, Grizante Barião PH, Nascimento E, Martinez R, von Zeska Kress MR. Surveillance of Amphotericin B and Azole Resistance in Aspergillus Isolated from Patients in a Tertiary Teaching Hospital. J Fungi (Basel) 2023; 9:1070. [PMID: 37998875 PMCID: PMC10672583 DOI: 10.3390/jof9111070] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2023] [Revised: 10/08/2023] [Accepted: 10/09/2023] [Indexed: 11/25/2023] Open
Abstract
The genus Aspergillus harbors human infection-causing pathogens and is involved in the complex one-health challenge of antifungal resistance. Here, a 6-year retrospective study was conducted with Aspergillus spp. isolated from patients with invasive, chronic, and clinically suspected aspergillosis in a tertiary teaching hospital. A total of 64 Aspergillus spp. clinical isolates were investigated regarding molecular identification, biofilm, virulence in Galleria mellonella, antifungal susceptibility, and resistance to amphotericin B and azoles. Aspergillus section Fumigati (A. fumigatus sensu stricto, 62.5%) and section Flavi (A. flavus, 20.3%; A. parasiticus, 14%; and A. tamarii, 3.1%) have been identified. Aspergillus section Flavi clinical isolates were more virulent than section Fumigati clinical isolates. Furthermore, scant evidence supports a link between biofilm formation and virulence. The susceptibility of the Aspergillus spp. clinical isolates to itraconazole, posaconazole, voriconazole, and amphotericin B was evaluated. Most Aspergillus spp. clinical isolates (67.2%) had an AMB MIC value equal to or above 2 µg/mL, warning of a higher probability of therapeutic failure in the region under study. In general, the triazoles presented MIC values above the epidemiological cutoff value. The high triazole MIC values of A. fumigatus s.s. clinical isolates were investigated by sequencing the promoter region and cyp51A locus. The Cyp51A amino acid substitutions F46Y, M172V, N248T, N248K, D255E, and E427K were globally detected in 47.5% of A. fumigatus s.s. clinical isolates, and most of them are associated with high triazole MICs. Even so, the findings support voriconazole or itraconazole as the first therapeutic choice for treating Aspergillus infections. This study emphasizes the significance of continued surveillance of Aspergillus spp. infections to help overcome the gap in knowledge of the global fungal burden of infections and antifungal resistance, supporting public health initiatives.
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Affiliation(s)
- Lívia Maria Maciel da Fonseca
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão, Universidade de Sao Paulo, Ribeirao Preto 14040-903, Brazil; (L.M.M.d.F.); (L.T.); (P.H.G.B.)
| | - Vanessa Fávaro Braga
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão, Universidade de Sao Paulo, Ribeirao Preto 14040-903, Brazil; (L.M.M.d.F.); (L.T.); (P.H.G.B.)
| | - Ludmilla Tonani
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão, Universidade de Sao Paulo, Ribeirao Preto 14040-903, Brazil; (L.M.M.d.F.); (L.T.); (P.H.G.B.)
| | - Patrícia Helena Grizante Barião
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão, Universidade de Sao Paulo, Ribeirao Preto 14040-903, Brazil; (L.M.M.d.F.); (L.T.); (P.H.G.B.)
| | - Erika Nascimento
- Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirao Preto 14040-900, Brazil; (E.N.); (R.M.)
| | - Roberto Martinez
- Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirao Preto 14040-900, Brazil; (E.N.); (R.M.)
| | - Marcia Regina von Zeska Kress
- Departamento de Análises Clínicas, Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão, Universidade de Sao Paulo, Ribeirao Preto 14040-903, Brazil; (L.M.M.d.F.); (L.T.); (P.H.G.B.)
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Celia-Sanchez BN, Mangum B, Brewer M, Momany M. Analysis of Cyp51 protein sequences shows 4 major Cyp51 gene family groups across fungi. G3 (BETHESDA, MD.) 2022; 12:jkac249. [PMID: 36130263 PMCID: PMC9635630 DOI: 10.1093/g3journal/jkac249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 09/07/2022] [Indexed: 06/15/2023]
Abstract
Azole drugs target fungal sterol biosynthesis and are used to treat millions of human fungal infections each year. Resistance to azole drugs has emerged in multiple fungal pathogens including Candida albicans, Cryptococcus neoformans, Histoplasma capsulatum, and Aspergillus fumigatus. The most well-studied resistance mechanism in A. fumigatus arises from missense mutations in the coding sequence combined with a tandem repeat in the promoter of cyp51A, which encodes a cytochrome P450 enzyme in the fungal sterol biosynthesis pathway. Filamentous members of Ascomycota such as A. fumigatus have either 1 or 2 of 3 Cyp51 paralogs (Cyp51A, Cyp51B, and Cyp51C). Most previous research in A. fumigatus has focused on Cyp51A due to its role in azole resistance. We used the A. fumigatus Cyp51A protein sequence as the query in database searches to identify Cyp51 proteins across fungi. We found 435 Cyp51 proteins in 295 species spanning from early-diverging fungi (Blastocladiomycota, Chytridiomycota, Zoopagomycota, and Mucormycota) to late-diverging fungi (Ascomycota and Basidiomycota). We found these sequences formed 4 major Cyp51 groups: Cyp51, Cyp51A, Cyp51B, and Cyp51C. Surprisingly, we found all filamentous Ascomycota had a Cyp51B paralog, while only 50% had a Cyp51A paralog. We created maximum likelihood trees to investigate the evolution of Cyp51 in fungi. Our results suggest Cyp51 is present in all fungi with 3 paralogs emerging in Pezizomycotina, including Cyp51C which appears to have diverged from the progenitor of the Cyp51A and Cyp51B groups.
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Affiliation(s)
| | - Brandon Mangum
- Department of Plant Biology, University of Georgia, Athens, GA 30606, USA
| | - Marin Brewer
- Department of Plant Pathology, University of Georgia, Athens, GA 30606, USA
| | - Michelle Momany
- Department of Plant Biology, University of Georgia, Athens, GA 30606, USA
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5
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Ghobadi E, Saednia S, Emami S. Synthetic approaches and structural diversity of triazolylbutanols derived from voriconazole in the antifungal drug development. Eur J Med Chem 2022; 231:114161. [DOI: 10.1016/j.ejmech.2022.114161] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 12/24/2022]
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Low YS, Garcia MD, Lonhienne T, Fraser JA, Schenk G, Guddat LW. Triazolopyrimidine herbicides are potent inhibitors of Aspergillus fumigatus acetohydroxyacid synthase and potential antifungal drug leads. Sci Rep 2021; 11:21055. [PMID: 34702838 PMCID: PMC8548585 DOI: 10.1038/s41598-021-00349-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2021] [Accepted: 10/06/2021] [Indexed: 11/09/2022] Open
Abstract
Aspergillus fumigatus is a fungal pathogen whose effects can be debilitating and potentially fatal in immunocompromised patients. Current drug treatment options for this infectious disease are limited to just a few choices (e.g. voriconazole and amphotericin B) and these themselves have limitations due to potentially adverse side effects. Furthermore, the likelihood of the development of resistance to these current drugs is ever present. Thus, new treatment options are needed for this infection. A new potential antifungal drug target is acetohydroxyacid synthase (AHAS; EC 2.2.1.6), the first enzyme in the branched chain amino acid biosynthesis pathway, and a target for many commercial herbicides. In this study, we have expressed, purified and characterised the catalytic subunit of AHAS from A. fumigatus and determined the inhibition constants for several known herbicides. The most potent of these, penoxsulam and metosulam, have Ki values of 1.8 ± 0.9 nM and 1.4 ± 0.2 nM, respectively. Molecular modelling shows that these compounds are likely to bind into the herbicide binding pocket in a mode similar to Candida albicans AHAS. We have also shown that these two compounds inhibit A. fumigatus growth at a concentration of 25 µg/mL. Thus, AHAS inhibitors are promising leads for the development of new anti-aspergillosis therapeutics.
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Affiliation(s)
- Y S Low
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - M D Garcia
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - T Lonhienne
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - J A Fraser
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, 4072, Australia.,Australian Infectious Diseases Research Centre, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - G Schenk
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - L W Guddat
- School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD, 4072, Australia.
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Durand C, Maubon D, Cornet M, Wang Y, Aldebert D, Garnaud C. Can We Improve Antifungal Susceptibility Testing? Front Cell Infect Microbiol 2021; 11:720609. [PMID: 34568095 PMCID: PMC8461061 DOI: 10.3389/fcimb.2021.720609] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 08/23/2021] [Indexed: 11/24/2022] Open
Abstract
Systemic antifungal agents are increasingly used for prevention or treatment of invasive fungal infections, whose prognosis remains poor. At the same time, emergence of resistant or even multi-resistant strains is of concern as the antifungal arsenal is limited. Antifungal susceptibility testing (AFST) is therefore of key importance for patient management and antifungal stewardship. Current AFST methods, including reference and commercial types, are based on growth inhibition in the presence of an antifungal, in liquid or solid media. They usually enable Minimal Inhibitory Concentrations (MIC) to be determined with direct clinical application. However, they are limited by a high turnaround time (TAT). Several innovative methods are currently under development to improve AFST. Techniques based on MALDI-TOF are promising with short TAT, but still need extensive clinical validation. Flow cytometry and computed imaging techniques detecting cellular responses to antifungal stress other than growth inhibition are also of interest. Finally, molecular detection of mutations associated with antifungal resistance is an intriguing alternative to standard AFST, already used in routine microbiology labs for detection of azole resistance in Aspergillus and even directly from samples. It is still restricted to known mutations. The development of Next Generation Sequencing (NGS) and whole-genome approaches may overcome this limitation in the near future. While promising approaches are under development, they are not perfect and the ideal AFST technique (user-friendly, reproducible, low-cost, fast and accurate) still needs to be set up routinely in clinical laboratories.
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Affiliation(s)
| | - Danièle Maubon
- TIMC, Univ Grenoble Alpes, CNRS, Grenoble INP, Grenoble, France.,Parasitology-Mycology, CHU Grenoble Alpes, Grenoble, France
| | - Muriel Cornet
- TIMC, Univ Grenoble Alpes, CNRS, Grenoble INP, Grenoble, France.,Parasitology-Mycology, CHU Grenoble Alpes, Grenoble, France
| | | | | | - Cécile Garnaud
- TIMC, Univ Grenoble Alpes, CNRS, Grenoble INP, Grenoble, France.,Parasitology-Mycology, CHU Grenoble Alpes, Grenoble, France
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8
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Arastehfar A, Carvalho A, Houbraken J, Lombardi L, Garcia-Rubio R, Jenks J, Rivero-Menendez O, Aljohani R, Jacobsen I, Berman J, Osherov N, Hedayati M, Ilkit M, Armstrong-James D, Gabaldón T, Meletiadis J, Kostrzewa M, Pan W, Lass-Flörl C, Perlin D, Hoenigl M. Aspergillus fumigatus and aspergillosis: From basics to clinics. Stud Mycol 2021; 100:100115. [PMID: 34035866 PMCID: PMC8131930 DOI: 10.1016/j.simyco.2021.100115] [Citation(s) in RCA: 106] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The airborne fungus Aspergillus fumigatus poses a serious health threat to humans by causing numerous invasive infections and a notable mortality in humans, especially in immunocompromised patients. Mould-active azoles are the frontline therapeutics employed to treat aspergillosis. The global emergence of azole-resistant A. fumigatus isolates in clinic and environment, however, notoriously limits the therapeutic options of mould-active antifungals and potentially can be attributed to a mortality rate reaching up to 100 %. Although specific mutations in CYP 51A are the main cause of azole resistance, there is a new wave of azole-resistant isolates with wild-type CYP 51A genotype challenging the efficacy of the current diagnostic tools. Therefore, applications of whole-genome sequencing are increasingly gaining popularity to overcome such challenges. Prominent echinocandin tolerance, as well as liver and kidney toxicity posed by amphotericin B, necessitate a continuous quest for novel antifungal drugs to combat emerging azole-resistant A. fumigatus isolates. Animal models and the tools used for genetic engineering require further refinement to facilitate a better understanding about the resistance mechanisms, virulence, and immune reactions orchestrated against A. fumigatus. This review paper comprehensively discusses the current clinical challenges caused by A. fumigatus and provides insights on how to address them.
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Affiliation(s)
- A. Arastehfar
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, 07110, USA
| | - A. Carvalho
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B's - PT Government Associate Laboratory, Guimarães/Braga, Portugal
| | - J. Houbraken
- Westerdijk Fungal Biodiversity Institute, Utrecht, the Netherlands
| | - L. Lombardi
- UCD Conway Institute and School of Medicine, University College Dublin, Dublin 4, Ireland
| | - R. Garcia-Rubio
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, 07110, USA
| | - J.D. Jenks
- Department of Medicine, University of California San Diego, San Diego, CA, 92103, USA
- Clinical and Translational Fungal-Working Group, University of California San Diego, La Jolla, CA, 92093, USA
| | - O. Rivero-Menendez
- Medical Mycology Reference Laboratory, National Center for Microbiology, Instituto de Salud Carlos III, Madrid, 28222, Spain
| | - R. Aljohani
- Department of Infectious Diseases, Imperial College London, London, UK
| | - I.D. Jacobsen
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology—Hans Knöll Institute, Jena, Germany
- Institute for Microbiology, Friedrich Schiller University, Jena, Germany
| | - J. Berman
- Research Group Microbial Immunology, Leibniz Institute for Natural Product Research and Infection Biology—Hans Knöll Institute, Jena, Germany
| | - N. Osherov
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine Ramat-Aviv, Tel-Aviv, 69978, Israel
| | - M.T. Hedayati
- Invasive Fungi Research Center/Department of Medical Mycology, School of Medicine, Mazandaran University of Medical Sciences, Sari, Iran
| | - M. Ilkit
- Division of Mycology, Department of Microbiology, Faculty of Medicine, Çukurova University, 01330, Adana, Turkey
| | | | - T. Gabaldón
- Life Sciences Programme, Supercomputing Center (BSC-CNS), Jordi Girona, Barcelona, 08034, Spain
- Mechanisms of Disease Programme, Institute for Research in Biomedicine (IRB), Barcelona, Spain
- ICREA, Pg. Lluís Companys 23, Barcelona, Spain
- Institució Catalana de Recerca i Estudis Avançats (ICREA), Pg. Lluís Companys 23, 08010, Barcelona, Spain
| | - J. Meletiadis
- Clinical Microbiology Laboratory, Attikon University Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | | | - W. Pan
- Medical Mycology, Shanghai Changzheng Hospital, Second Military Medical University, Shanghai, 200003, China
| | - C. Lass-Flörl
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - D.S. Perlin
- Center for Discovery and Innovation, Hackensack Meridian Health, Nutley, NJ, 07110, USA
| | - M. Hoenigl
- Department of Medicine, University of California San Diego, San Diego, CA, 92103, USA
- Section of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Medical University of Graz, 8036, Graz, Austria
- Division of Infectious Diseases and Global Public Health, Department of Medicine, University of California San Diego, San Diego, CA 92093, USA
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Jørgensen KM, Guinea J, Meletiadis J, Hare RK, Arendrup MC. Revision of EUCAST breakpoints: consequences for susceptibility of contemporary Danish mould isolates to isavuconazole and comparators. J Antimicrob Chemother 2021; 75:2573-2581. [PMID: 32556315 DOI: 10.1093/jac/dkaa212] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 04/16/2020] [Accepted: 04/23/2020] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND EUCAST recently revised the definition of the 'I' category from 'intermediate' to 'susceptible, increased exposure'. Consequently, all current antifungal breakpoints have been reviewed and revised breakpoints (v 10.0) have been released. OBJECTIVES We investigated isavuconazole and comparator MICs (mg/L) against contemporary moulds and the consequences of the breakpoint revision for susceptibility classification. METHODS Six hundred and ninety-six Aspergillus and 46 other moulds were included. EUCAST E.Def 10.1 azole resistance screening was performed for Aspergillus fumigatus and E.Def 9.3.1 testing of non-susceptible A. fumigatus and other moulds. Most non-wildtype/resistant isolates underwent cyp51A sequencing. RESULTS Isavuconazole MIC50/MIC90s were ≤1/≤2 mg/L for Aspergillus flavus, A. fumigatus and Aspergillus nidulans versus 2/4 mg/L for Aspergillus niger and 2/16 mg/L for Aspergillus terreus. For the remaining moulds, MICs were highest for Fusarium (16 to >16 mg/L), lowest for dermatophytes (0.06-0.5 mg/L) and in between for Mucorales and others (1 to >16 mg/L). A very strong isavuconazole-voriconazole MIC correlation was found for A. fumigatus (Pearson r = 0.888) and itraconazole-posaconazole correlation for A. fumigatus (r = 0.905) and A. terreus (r = 0.848). For A. fumigatus, the revised breakpoints lowered isavuconazole resistance (22.6% to 7.7%, P < 0.0001) and increased voriconazole resistance (3.8% to 6.7%, P = 0.025), resulting in similar resistance rates across the four azoles (range: 6.7%-7.7%). For A. terreus, isavuconazole resistance remained unchanged (81.3%) and higher than itraconazole (43.8%, P = 0.004) and posaconazole (53.1%, P = 0.03) resistance. Azole cross-resistance was found in 24/24, 13/20 and 4/90 isolates, and Cyp51A alterations in 16/18, 1/7 and 2/4 sequenced isolates with isavuconazole MICs of >4, 4 and 2 mg/L, respectively. CONCLUSIONS Isavuconazole displays broad anti-mould activity. The revised breakpoints result in fewer misclassifications of wildtype isolates without compromising detection of resistant mutants.
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Affiliation(s)
| | - Jesus Guinea
- Clinical Microbiology and Infectious Diseases Department, Hospital General Universitario Gregorio Marañón, Madrid, Spain.,CIBER Enfermedades Respiratorias-CIBERES (CB06/06/0058), Madrid, Spain
| | - Joseph Meletiadis
- Clinical Microbiology Laboratory, Attikon University Hospital, Athens, Greece
| | | | - Maiken Cavling Arendrup
- Unit for Mycology, Statens Serum Institut, Copenhagen, Denmark.,Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark.,Department of Clinical Medicine, Copenhagen University, Copenhagen, Denmark
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THE ISOLATION AND ANTIMICROBIAL SENSITIVITY OF ASPERGILLUS FUMIGATUS FROM FROZEN RESPIRATORY TISSUES OF PENGUINS FROM ZOOLOGICAL COLLECTIONS IN THE UNITED KINGDOM, 2007-2018. J Zoo Wildl Med 2021; 51:591-597. [PMID: 33480534 DOI: 10.1638/2019-0160] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/23/2020] [Indexed: 11/21/2022] Open
Abstract
Fifty-eight frozen postmortem lung and air sac samples were collected from penguins housed at 21 zoological collections throughout the United Kingdom, from 2007 to 2018. Aspergillus fumigatus, a significant respiratory pathogen of penguins in captivity, was isolated from 15 of the 22 penguins with gross lesions. Of the penguins with gross lesions of aspergillosis at postmortem examination, the pathogen was cultured from 63.6% (15 of 22) of frozen samples. Aspergillus fumigatus was cultured from 2.7% (1 of 36) of tissues collected from penguins without gross lesions at postmortem. Additionally, of 18 fresh samples that cultured A. fumigatus at the time of postmortem, 15 samples (83%) yielded isolates that were successfully cultured from frozen tissue. Minimum inhibitory concentration (MIC) data demonstrated that all isolates were susceptible to terbinafine and voriconazole, and all were resistant to itraconazole, using published MIC cutoff values. Comparison isolates from fresh tissues had identical antimicrobial susceptibility to isolates from the same tissues after being frozen. This study demonstrates that A. fumigatus can be isolated from frozen respiratory tissues of penguins, even after freezing for more than 10 yr.
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Wang F, Yao S, Cao D, Ju C, Yu S, Xu S, Fang H, Yu Y. Increased triazole-resistance and cyp51A mutations in Aspergillus fumigatus after selection with a combination of the triazole fungicides difenoconazole and propiconazole. JOURNAL OF HAZARDOUS MATERIALS 2020; 400:123200. [PMID: 32593937 DOI: 10.1016/j.jhazmat.2020.123200] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 06/09/2020] [Accepted: 06/10/2020] [Indexed: 06/11/2023]
Abstract
Triazole-resistance in Aspergillus fumigatus is widespread. We evaluated whether triazole-resistance in A. fumigatus and its related cyp51A mutations, induced by a combination of the triazole fungicides difenoconazole and propiconazole, differs from resistance induced by the individual fungicides. Both difenoconazole and propiconazole can induce triazole-resistance in A. fumigatus. Resistance is much easier induced by formulated fungicides or a combination of these two fungicides compared with standard fungicides or individual fungicides, respectively. Six different mutations (G138S, G138D, H147Y, I246M, M263I and D430N) were identified in the induced resistant strains. The H147Y, I246M and M263I mutations were associated with triazole-resistance. This implies that the application of a combination of difenoconazole and propiconazole may result in higher triazole-resistance in A. fumigatus and more mutations in the cyp51A gene.
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Affiliation(s)
- Feiyan Wang
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Shijie Yao
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Duantao Cao
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Chao Ju
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Sumei Yu
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Shiji Xu
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Hua Fang
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, 310058, China
| | - Yunlong Yu
- Institute of Pesticide and Environmental Toxicology, the Key Laboratory of Molecular Biology of Crop Pathogens and Insects, College of Agricultural and Biotechnology, Zhejiang University, Hangzhou, 310058, China.
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Viegas C, Dias M, Almeida B, Vicente E, Caetano LA, Carolino E, Alves C. Settleable Dust and Bioburden in Portuguese Dwellings. Microorganisms 2020; 8:microorganisms8111799. [PMID: 33207843 PMCID: PMC7698071 DOI: 10.3390/microorganisms8111799] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 11/12/2020] [Accepted: 11/14/2020] [Indexed: 12/13/2022] Open
Abstract
Monitoring campaigns in several buildings have shown that occupants exposed to contaminated indoor air generally exhibit diverse health symptoms. This study intends to assess settleable dust loading rates and bioburden in Portuguese dwellings by passive sampling onto quartz fiber filters and electrostatic dust cloths (EDCs), respectively. Settled dust collected by EDCs was analyzed by culture-based methods (including azole-resistance screening) and qPCR, targeting four different toxigenic Aspergillus sections (Flavi, Fumigati, Circumdati, and Nidulantes). Dust loading rates and bioburden showed higher variability in the summer season. In both seasons, Penicillium sp. was the one with the highest prevalence (59.1% winter; 58.1% summer), followed by Aspergillus sp. in winter (13.0%). Fungal contamination increased in the winter period, while bacterial counts decreased. Aspergillus sections Circumdati and Nidulantes, detected in voriconazole supplemented media, and Aspergillus sections Fumigati and Nidulantes, detected by molecular tools, were found in the winter samples. This study reinforces the importance of applying: (a) Passive sampling methods in campaigns in dwellings; (b) two different culture media (MEA and DG18) to assess fungi; (c) in parallel, molecular tools targeting the most suitable indicators of fungal contamination; and (d) azole resistance screening to unveil azole resistance detection in fungal species.
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Affiliation(s)
- Carla Viegas
- H&TRC-Health & Technology Research Center, ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal; (M.D.); (B.A.); (L.A.C.); (E.C.)
- NOVA National School of Public Health, Public Health Research Centre, Universidade NOVA de Lisboa, 1600-560 Lisboa, Portugal
- Comprehensive Health Research Center (CHRC), 1169-056 Lisbon, Portugal
- Correspondence:
| | - Marta Dias
- H&TRC-Health & Technology Research Center, ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal; (M.D.); (B.A.); (L.A.C.); (E.C.)
| | - Beatriz Almeida
- H&TRC-Health & Technology Research Center, ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal; (M.D.); (B.A.); (L.A.C.); (E.C.)
| | - Estela Vicente
- Department of Environment and Planning, Centre for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193 Aveiro, Portugal; (E.V.); (C.A.)
| | - Liliana Aranha Caetano
- H&TRC-Health & Technology Research Center, ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal; (M.D.); (B.A.); (L.A.C.); (E.C.)
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 1649-003 Lisbon, Portugal
| | - Elisabete Carolino
- H&TRC-Health & Technology Research Center, ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal; (M.D.); (B.A.); (L.A.C.); (E.C.)
| | - Célia Alves
- Department of Environment and Planning, Centre for Environmental and Marine Studies (CESAM), University of Aveiro, 3810-193 Aveiro, Portugal; (E.V.); (C.A.)
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The Effect of Posaconazole, Itraconazole and Voriconazole in the Culture Medium on Aspergillus fumigatus Triazole Resistance. Microorganisms 2020; 8:microorganisms8020285. [PMID: 32093114 PMCID: PMC7094209 DOI: 10.3390/microorganisms8020285] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 02/13/2020] [Accepted: 02/17/2020] [Indexed: 02/02/2023] Open
Abstract
Triazoles are the only compounds used as antibiotics in both medicine and agriculture. The presence of triazoles in the environment can contribute to the acquisition of azole resistance among isolates of Aspergillus fumigatus. The objective of this study was to investigate the effect of A.fumigatus exposure to triazoles on susceptibility to these compounds. Seventeen triazole-resistant and 21 triazole-sensitive A.fumigatus isolates were examined. The isolates were transferred 20 times on the Sabouraud medium supplemented with posaconazole, itraconazole or voriconazole, followed by five times on the medium not supplemented. The minimum inhibitory concentrations of antimycotics were examined according to the EUCAST broth microdilution method after the 20th transfer and also the 25th transfer. In addition, the expression levels of genes mdr1, mdr2, mdr3, atrF, cyp51A and cyp51B were determined. Cultivation of A. fumigatus on media supplemented with posaconazole, itraconazole and voriconazole resulted in the acquisition of resistance to the tested triazoles of all examined isolates. After recultivation on Sabouraud without azoles, most of the isolates lost their acquired resistance. The long-term use of triazole compounds in agriculture may result in the occurrence of triazole resistant A. fumigatus isolates in the environment, not only by induction or selection of mutations in the cyp51A gene, but also by contribution to changes in the gene expression.
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Effective plasma concentrations of itraconazole and its active metabolite for the treatment of pulmonary aspergillosis. J Infect Chemother 2020; 26:170-174. [DOI: 10.1016/j.jiac.2019.08.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 07/30/2019] [Accepted: 08/05/2019] [Indexed: 11/18/2022]
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Morio F. Dear medical mycologists, it is time to look outside the box. FEMS Yeast Res 2020; 20:5628327. [PMID: 31738413 DOI: 10.1093/femsyr/foz080] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 11/16/2019] [Indexed: 12/22/2022] Open
Abstract
Opulente et al. (Opulente DA, Langdon QK, Buh KV et al. Pathogenic budding yeasts isolated outside of clinical settings. FEMS Yeast Res 2019;19:foz032) published early this year a study aiming to investigate the diversity of wild yeast species, by collecting 1000 environmental samples coming from different substrates across the United States of America. The main finding of this work is the recovery of 54 strains of budding yeasts of which several are having a pathogenic potential in the clinical setting, such as Candida albicans, C. parapsilosis, C. tropicalis, Nakaseomyces glabrata and Pichia kudriavzevii. These findings, discussed here in light of other recent studies highlighting the role of fungicides in the rise of antifungal resistance in the clinical setting or the emergence of Candida auris, demonstrate that our environment can represent an alternative niche for several opportunistic fungal pathogens that can be a concern for human health.
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Affiliation(s)
- Florent Morio
- Laboratoire de Parasitologie-Mycologie, Institut de Biologie, 9 Quai Moncousu, CHU Nantes, 44093 Nantes, France
- Département de Parasitologie et Mycologie Médicale, EA1155 - IICiMed, Institut de Recherche en Santé 2, Nantes Université, 22 Boulevard Bénoni-Goullin, 44200 Nantes, France
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16
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Viegas C, Dias M, Almeida B, Aranha Caetano L, Carolino E, Quintal Gomes A, Twarużek M, Kosicki R, Grajewski J, Marchand G, Viegas S. Are workers from waste sorting industry really protected by wearing Filtering Respiratory Protective Devices? The gap between the myth and reality. WASTE MANAGEMENT (NEW YORK, N.Y.) 2020; 102:856-867. [PMID: 31835063 DOI: 10.1016/j.wasman.2019.12.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 11/28/2019] [Accepted: 12/02/2019] [Indexed: 05/22/2023]
Abstract
One of the solutions for decreasing the workers' exposure to bioburden is the use of Filtering Respiratory Protective Devices (FRPD). As such it is important to determine whether these devices are fulfilling their protective role. This is the basis of the current study, aimed at characterizing bioburden retained by 120 FRPD (both in interior layers and in exhalation valves) through culture based-methods and molecular tools and also via analysis of antifungal resistance and mycotoxins profile. Our results show that Gram - Bacteria are present at a higher prevalence than total bacteria in both matrixes. Regarding fungal identification, Chrysonilia sitophila presented the highest prevalence on interior layers (55.1% on malt extract agar (MEA) supplemented with chloramphenicol (0.05%); 59.6% on dichloran-glycerol agar (DG18)), whereas on exhalation valves Aspergillus sp. presented the highest prevalence on MEA (6.8%) and C. sitophila on DG18 (36.3%). Among Aspergillus genera, section Fumigati was the one with the highest prevalence in both matrices. Aspergillus sp. was the most prevalent on exhalation valves (75.0% ITRA) in the screening of azole resistance. Fumigati section was the most abundant Aspergillus sp. detected on the interior layers (33.33%, 40 samples out of 120) and on the exhalation valves (1.66%, 2 samples out of 120). The interior layers and exhalation valves from workers with more waste contact showed an increased exposure to bioburden. This study showed that FRPD can have high levels of bioburden, toxigenic fungal strains and Aspergillus sections with reduced susceptibility to the tested azoles and can be used as a passive sampling method since it mimics the results obtained by active methods in previous studies. The gathered information will be useful to prioritize multiple interventions on workers' education or even on FRPD replacement frequency.
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Affiliation(s)
- Carla Viegas
- H&TRC - Health & Technology Research Center, ESTeSL - Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Portugal; Centro de Investigação em Saúde Pública, Universidade NOVA de Lisboa, 1600-560 Lisbon, Portugal.
| | - Marta Dias
- H&TRC - Health & Technology Research Center, ESTeSL - Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Portugal
| | - Beatriz Almeida
- H&TRC - Health & Technology Research Center, ESTeSL - Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Portugal
| | - Liliana Aranha Caetano
- H&TRC - Health & Technology Research Center, ESTeSL - Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Portugal; Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, Lisbon, Portugal
| | - Elisabete Carolino
- H&TRC - Health & Technology Research Center, ESTeSL - Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Portugal
| | - Anita Quintal Gomes
- H&TRC - Health & Technology Research Center, ESTeSL - Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Portugal; University of Lisbon Institute of Molecular Medicine, Faculty of Medicine, Lisbon, Portugal
| | - Magdalena Twarużek
- Kazimierz Wielki University, Faculty of Biological Sciences, Department of Physiology and Toxicology, Chodkiewicza 30, 85-064 Bydgoszcz, Poland
| | - Robert Kosicki
- Kazimierz Wielki University, Faculty of Biological Sciences, Department of Physiology and Toxicology, Chodkiewicza 30, 85-064 Bydgoszcz, Poland
| | - Jan Grajewski
- Kazimierz Wielki University, Faculty of Biological Sciences, Department of Physiology and Toxicology, Chodkiewicza 30, 85-064 Bydgoszcz, Poland
| | - Geneviève Marchand
- Institut de recherche Robert-Sauvé en santé et sécurité du travail, Montréal, Canada
| | - Susana Viegas
- H&TRC - Health & Technology Research Center, ESTeSL - Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, Portugal; Centro de Investigação em Saúde Pública, Universidade NOVA de Lisboa, 1600-560 Lisbon, Portugal
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17
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Viegas C, Fleming GTA, Kadir A, Almeida B, Caetano LA, Quintal Gomes A, Twarużek M, Kosicki R, Viegas S, Coggins AM. Occupational Exposures to Organic Dust in Irish Bakeries and a Pizzeria Restaurant. Microorganisms 2020; 8:E118. [PMID: 31952269 PMCID: PMC7022993 DOI: 10.3390/microorganisms8010118] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 01/10/2020] [Accepted: 01/12/2020] [Indexed: 11/16/2022] Open
Abstract
For decades, occupational exposure to flour dust has been linked to a range of respiratory diseases, including occupational asthma, thought to result from exposure to fungi present in the flour. Antifungal resistance is of increasing prevalence in clinical settings, and the role of occupational and environmental exposures, particularly for specific fungal species, is of concern. Occupational exposure to flour dust can occur in a range of occupational settings, however, few studies have focused on restaurant workers. The objective of this study was to measure occupational exposure to flour and microbial contamination, including azole resistance screening, in two small commercial bakeries and in a pizzeria. Personal full shift inhalable dust measurements were collected from workers, and were analyzed for inhalable dust and fungi, bacteria, azole resistance, and mycotoxins. Samples of settled dust were collected, and electrostatic dust cloths (EDC) were deployed and analyzed for microbial contamination, including azole resistance screening, and mycotoxins. Geometric mean exposures of 6.5 mg m-³ were calculated for inhalable dust, however, exposures of up to 18.30 mg m-³ were measured-70% of personal exposure measurements exceeded the occupational exposure limit for flour dust of 1.0 mg m-³. The air and EDC fungal counts were similar to those reported in previous studies for similar occupational environments. The fungi were dominated by Penicillium genera, however Aspergillus genera, including Fumigati and Flavi sections, were observed using culture-based methods, and the Fumigati section was also observed by molecular tools. Both Aspergillus sections were identified on the azole resistance screening. Mycotoxins were also detected in the settled dust samples, dominated by deoxynivalenol (DON). The role of environmental exposure in both the development of antimicrobial resistance and the total mycotoxin body burden is a growing concern; therefore, the presence of azole-resistant fungi and mycotoxin contamination, although low in magnitude, is of concern and warrants further investigation.
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Affiliation(s)
- Carla Viegas
- H&TRC-Health & Technology Research Center, ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal; (B.A.); (L.A.C.); (A.Q.G.)
- NOVA National School of Public Health, Public Health Research Centre, Universidade NOVA de Lisboa, 1600-560 Lisbon, Portugal
- Comprehensive Health Research Center (CHRC), 1150-090 Lisbon, Portugal
| | - Gerard T. A. Fleming
- School of Natural Sciences and Ryan Institute, National University of Ireland, H91 CF50 Galway, Ireland;
| | - Abdul Kadir
- School of Physics and Ryan Institute, National University of Ireland, H91 CF50 Galway, Ireland;
| | - Beatriz Almeida
- H&TRC-Health & Technology Research Center, ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal; (B.A.); (L.A.C.); (A.Q.G.)
| | - Liliana Aranha Caetano
- H&TRC-Health & Technology Research Center, ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal; (B.A.); (L.A.C.); (A.Q.G.)
- Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, University of Lisbon, 1649-003 Lisbon, Portugal
| | - Anita Quintal Gomes
- H&TRC-Health & Technology Research Center, ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal; (B.A.); (L.A.C.); (A.Q.G.)
- Institute of Molecular Medicine, Faculty of Medicine, University of Lisbon, 1649-028 Lisbon, Portugal
| | - Magdalena Twarużek
- Department of Physiology and Toxicology, Faculty of Biological Sciences, Kazimierz Wielki University, Chodkiewicza 30, 85–064 Bydgoszcz, Poland; (M.T.); (R.K.)
| | - Robert Kosicki
- Department of Physiology and Toxicology, Faculty of Biological Sciences, Kazimierz Wielki University, Chodkiewicza 30, 85–064 Bydgoszcz, Poland; (M.T.); (R.K.)
| | - Susana Viegas
- H&TRC-Health & Technology Research Center, ESTeSL-Escola Superior de Tecnologia da Saúde, Instituto Politécnico de Lisboa, 1990-096 Lisbon, Portugal; (B.A.); (L.A.C.); (A.Q.G.)
- NOVA National School of Public Health, Public Health Research Centre, Universidade NOVA de Lisboa, 1600-560 Lisbon, Portugal
- Comprehensive Health Research Center (CHRC), 1150-090 Lisbon, Portugal
| | - Ann Marie Coggins
- School of Physics and Ryan Institute, National University of Ireland, H91 CF50 Galway, Ireland;
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ASP2397 Is a Novel Natural Compound That Exhibits Rapid and Potent Fungicidal Activity against Aspergillus Species through a Specific Transporter. Antimicrob Agents Chemother 2019; 63:AAC.02689-18. [PMID: 31405853 DOI: 10.1128/aac.02689-18] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 07/28/2019] [Indexed: 11/20/2022] Open
Abstract
Current therapies against invasive pulmonary aspergillosis (IPA) have a limited cure rate. Given that a delay in treatment initiation may be fatal, a new drug with rapid-onset and potent fungicidal activity is needed. The novel cyclic hexapeptide ASP2397 (currently known as VL-2397) exhibited antifungal activity against Aspergillus fumigatus (including azole-sensitive and azole-resistant isolates), A. terreus, and A. flavus at an MIC range of 1 to 4 μg/ml in human serum. Time-kill curve experiments showed that ASP2397 reduced germinated conidia of A. fumigatus by more than 1 log10 CFU within 6 h. In addition, ASP2397 inhibited hyphal elongation from germinated conidia of A. fumigatus, A. terreus, and A. flavus more rapidly than voriconazole. Under conditions of delayed treatment initiation in an IPA mouse model, ASP2397 had efficacy superior to that of posaconazole, with 100% survival and over 1 log10 CFU/g reduction in lung fungal burden. Histopathological investigation of lungs also showed that ASP2397 markedly suppressed disease progression. To clarify its mechanism of action, we generated a UV-induced mutant of A. fumigatus with low susceptibility to ASP2397. The mutant had a point mutation in the siderophore transporter gene sit1, which is absent in mammalian cells. These findings suggest that ASP2397 may improve clinical treatment options for IPA.
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Ballard E, Weber J, Melchers WJG, Tammireddy S, Whitfield PD, Brakhage AA, Brown AJP, Verweij PE, Warris A. Recreation of in-host acquired single nucleotide polymorphisms by CRISPR-Cas9 reveals an uncharacterised gene playing a role in Aspergillus fumigatus azole resistance via a non-cyp51A mediated resistance mechanism. Fungal Genet Biol 2019; 130:98-106. [PMID: 31128273 PMCID: PMC6876285 DOI: 10.1016/j.fgb.2019.05.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 05/19/2019] [Accepted: 05/20/2019] [Indexed: 02/06/2023]
Abstract
The human host comprises a range of specific niche environments. In order to successfully persist, pathogens such as Aspergillus fumigatus must adapt to these environments. One key example of in-host adaptation is the development of resistance to azole antifungals. Azole resistance in A. fumigatus is increasingly reported worldwide and the most commonly reported mechanisms are cyp51A mediated. Using a unique series of A. fumigatus isolates, obtained from a patient suffering from persistent and recurrent invasive aspergillosis over 2 years, this study aimed to gain insight into the genetic basis of in-host adaptation. Single nucleotide polymorphisms (SNPs) unique to a single isolate in this series, which had developed multi-azole resistance in-host, were identified. Two nonsense SNPs were recreated using CRISPR-Cas9; these were 213* in svf1 and 167* in uncharacterised gene AFUA_7G01960. Phenotypic analyses including antifungal susceptibility testing, mycelial growth rate assessment, lipidomics analysis and statin susceptibility testing were performed to associate genotypes to phenotypes. This revealed a role for svf1 in A. fumigatus oxidative stress sensitivity. In contrast, recapitulation of 167* in AFUA_7G01960 resulted in increased itraconazole resistance. Comprehensive lipidomics analysis revealed decreased ergosterol levels in strains containing this SNP, providing insight to the observed itraconazole resistance. Decreases in ergosterol levels were reflected in increased resistance to lovastatin and nystatin. Importantly, this study has identified a SNP in an uncharacterised gene playing a role in azole resistance via a non-cyp51A mediated resistance mechanism. This mechanism is of clinical importance, as this SNP was identified in a clinical isolate, which acquired azole resistance in-host.
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Affiliation(s)
- Eloise Ballard
- MRC Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, UK
| | - Jakob Weber
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Jena, Germany
| | - Willem J G Melchers
- Centre for Expertise in Mycology and Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, the Netherlands
| | - Seshu Tammireddy
- Lipidomics Research Facility, Division of Biomedical Sciences, University of the Highlands and Islands, UK
| | - Phillip D Whitfield
- Lipidomics Research Facility, Division of Biomedical Sciences, University of the Highlands and Islands, UK
| | - Axel A Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Jena, Germany
| | - Alistair J P Brown
- MRC Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, UK
| | - Paul E Verweij
- Centre for Expertise in Mycology and Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, the Netherlands
| | - Adilia Warris
- MRC Centre for Medical Mycology at the University of Aberdeen, Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, UK.
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20
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Zhang J, Li L, Lv Q, Yan L, Wang Y, Jiang Y. The Fungal CYP51s: Their Functions, Structures, Related Drug Resistance, and Inhibitors. Front Microbiol 2019; 10:691. [PMID: 31068906 PMCID: PMC6491756 DOI: 10.3389/fmicb.2019.00691] [Citation(s) in RCA: 104] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2018] [Accepted: 03/19/2019] [Indexed: 12/18/2022] Open
Abstract
CYP51 (Erg11) belongs to the cytochrome P450 monooxygenase (CYP) superfamily and mediates a crucial step of the synthesis of ergosterol, which is a fungal-specific sterol. It is also the target of azole drugs in clinical practice. In recent years, researches on fungal CYP51 have stepped into a new stage attributing to the discovery of crystal structures of the homologs in Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus. This review summarizes the functions, structures of fungal CYP51 proteins, and the inhibitors targeting these homologs. In particular, several drug-resistant mechanisms associated with the fungal CYP51s are introduced. The sequences and crystal structures of CYP51 proteins in different fungal species are also compared. These will provide new insights for the advancement of research on antifungal agents.
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Affiliation(s)
- Jingxiang Zhang
- Center for New Drug Research, School of Pharmacy, Second Military Medical University, Shanghai, China
| | - Liping Li
- Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, China
- Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
| | - Quanzhen Lv
- Center for New Drug Research, School of Pharmacy, Second Military Medical University, Shanghai, China
| | - Lan Yan
- Center for New Drug Research, School of Pharmacy, Second Military Medical University, Shanghai, China
- *Correspondence: Lan Yan, Yan Wang, Yuanying Jiang,
| | - Yan Wang
- Center for New Drug Research, School of Pharmacy, Second Military Medical University, Shanghai, China
- *Correspondence: Lan Yan, Yan Wang, Yuanying Jiang,
| | - Yuanying Jiang
- Center for New Drug Research, School of Pharmacy, Second Military Medical University, Shanghai, China
- Shanghai Tenth People’s Hospital, Tongji University School of Medicine, Shanghai, China
- Department of Pharmacology, Tongji University School of Medicine, Shanghai, China
- *Correspondence: Lan Yan, Yan Wang, Yuanying Jiang,
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21
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Arikan-Akdagli S, Ghannoum M, Meis JF. Antifungal Resistance: Specific Focus on Multidrug Resistance in Candida auris and Secondary Azole Resistance in Aspergillus fumigatus. J Fungi (Basel) 2018; 4:jof4040129. [PMID: 30563053 PMCID: PMC6308933 DOI: 10.3390/jof4040129] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 11/29/2018] [Accepted: 12/03/2018] [Indexed: 12/20/2022] Open
Abstract
Antifungal resistance is a topic of concern, particularly for specific fungal species and drugs. Among these are the multidrug-resistant Candida auris and azole-resistant Aspergillus fumigatus. While the knowledge on molecular mechanisms of resistance is now accumulating, further data are also available for the clinical implications and the extent of correlation of in vitro resistance to clinical outcomes. This review article summarizes the epidemiology of C. auris infections, animal models focusing on the activity of novel antifungal compounds in C. auris infections, virulence factors, and the mechanisms of antifungal resistance for this multi-resistant Candida species. Regarding A. fumigatus, the significance of azoles in the treatment of A. fumigatus infections, reference methods available for the detection of resistance in vitro, molecular mechanisms of secondary azole resistance, routes of acquisition, and clinical implications of in vitro resistance are covered to provide guidance for the current status of azole resistance in A. fumigatus.
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Affiliation(s)
- Sevtap Arikan-Akdagli
- Department of Medical Microbiology, Mycology Laboratory, Hacettepe University Medical School, TR-06100 Ankara, Turkey.
| | - Mahmoud Ghannoum
- Center for Medical Mycology, Department of Dermatology, University Hospitals Cleveland Medical Center, Case Western Reserve University, Cleveland, OH 44106, USA.
| | - Jacques F Meis
- Department of Medical Microbiology and Infectious Diseases, Canisius Wilhelmina Hospital (CWZ), 6532 Nijmegen, The Netherlands.
- Centre of Expertise in Mycology Radboudumc/CWZ, 6532 Nijmegen, The Netherlands.
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22
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Lackner M, Rambach G, Jukic E, Sartori B, Fritz J, Seger C, Hagleitner M, Speth C, Lass-Flörl C. Azole-resistant and -susceptible Aspergillus fumigatus isolates show comparable fitness and azole treatment outcome in immunocompetent mice. Med Mycol 2018; 56:703-710. [PMID: 29228287 DOI: 10.1093/mmy/myx109] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 10/05/2017] [Indexed: 11/15/2022] Open
Abstract
No data are available on the in vivo impact of infections with in vitro azole-resistant Aspergillus fumigatus in immunocompetent hosts. Here, the aim was to investigate fungal fitness and treatment response in immunocompetent mice infected with A. fumigatus (parental strain [ps]) and isogenic mutants carrying either the mutation M220K or G54W (cyp51A). The efficacy of itraconazole (ITC) and posaconazole (PSC) was investigated in mice, intravenously challenged either with a single or a combination of ps and mutants (6 × 105 conidia/mouse). Organ fungal burden and clinical parameters were measured. In coinfection models, no fitness advantage was observed for the ps strain when compared to the mutants (M220K and G54W) independent of the presence or absence of azole-treatment. For G54W, M220K, and the ps, no statistically significant difference in ITC and PSC treatment was observed in respect to fungal kidney burden. However, clinical parameters suggest that in particular the azole-resistant strain carrying the mutation G54W caused a more severe disease than the ps strain. Mice infected with G54W showed a significant decline in body weight and lymphocyte counts, while spleen/body weight ratio and granulocyte counts were increased. In immunocompetent mice, in vitro azole-resistance did not translate into therapeutic failure by either ITC or PSC; the immune system appears to play the key role in clearing the infection.
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Affiliation(s)
- Michaela Lackner
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Günter Rambach
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Emina Jukic
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Bettina Sartori
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Josef Fritz
- Department for Medical Statistics, Informatics and Health Economics, Medical University of Innsbruck, Austria
| | - Christoph Seger
- Division of Mass Spectrometry and Chromatography, Institute of Medical and Chemical Laboratory Diagnostics (ZIMCL), University Hospital Innsbruck, Innsbruck, Austria
| | - Magdalena Hagleitner
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Cornelia Speth
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
| | - Cornelia Lass-Flörl
- Division of Hygiene and Medical Microbiology, Medical University of Innsbruck, Innsbruck, Austria
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Abstract
Fungi of the genus Aspergillus are ubiquitously present. Even though humans inhale Aspergillus spores daily under natural conditions, Aspergillus-associated pulmonary diseases only occur under special circumstances. Whether an Aspergillus-associated disease develops and which type of Aspergillus-associated disease develops depends on the constitution of the host. The spectrum of Aspergillus-associated pulmonary diseases ranges from allergic diseases, such as hypersensitivity pneumonitis to allergic infectious diseases, such as allergic bronchopulmonary aspergillosis (ABPA) and bronchocentric granulomatosis (BG) to infectious diseases, such as invasive (IA) or semi-invasive aspergillosis (SIA) and chronic pulmonary aspergillosis (CPA). Identification of Aspergillus spp. from sputum or bronchopulmonary secretions is not sufficient for a definitive diagnosis of Aspergillus-associated infections. The gold standard is the identification of Aspergillus spp. from lung tissue by culture or by histopathological methods; however, in clinical practice the decision to initiate antifungal therapy is more often based on immunological methods, such as the detection of Aspergillus-specific IgG antibodies from peripheral blood or galactomannan antigens from bronchoalveolar lavages. Acute IA or SIA infections have a high mortality and require immediate antifungal therapy. With rare exceptions CPA cannot be cured by medicinal therapy alone; however, active CPA can be brought into remission with antifungal therapy. Eradication of Aspergillus in CPA can as a rule only be successful using a combined antimycotic and surgical intervention.
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Affiliation(s)
- H J F Salzer
- Klinische Infektiologie, Medizinische Klinik, Forschungszentrum Borstel, Leibniz-Zentrum für Medizin und Biowissenschaften, Parkallee 35, 23845, Borstel, Deutschland.
- Hamburg - Borstel - Lübeck - Riems DZIF-Standort, Deutsches Zentrum für Infektionsforschung (DZIF), Borstel, Deutschland.
| | - C Lange
- Klinische Infektiologie, Medizinische Klinik, Forschungszentrum Borstel, Leibniz-Zentrum für Medizin und Biowissenschaften, Parkallee 35, 23845, Borstel, Deutschland
- Hamburg - Borstel - Lübeck - Riems DZIF-Standort, Deutsches Zentrum für Infektionsforschung (DZIF), Borstel, Deutschland
- International Health and Infectious Diseases, Universität zu Lübeck, Lübeck, Deutschland
- Department of Medicine, Karolinska Institute, Stockholm, Schweden
| | - M Hönigl
- Klinische Abteilung für Pulmonologie, Medizinische Universität Graz, Graz, Österreich
- Sektion für Infektionserkrankungen und Tropenmedizin, Medizinische Universität Graz, Graz, Österreich
- Division of Infectious Diseases, Department of Medicine, University of California - San Diego, San Diego, USA
- CBmed - Center for Biomarker Research in Medicine, Graz, Österreich
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Zhan M, Xu B, Zhao L, Li B, Xu L, Sun Q, Zhang J, Zhang Z, Chu H. The Serum Level of IL-1B Correlates with the Activity of Chronic Pulmonary Aspergillosis. Can Respir J 2018; 2018:8740491. [PMID: 30363691 PMCID: PMC6180967 DOI: 10.1155/2018/8740491] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2018] [Revised: 08/26/2018] [Accepted: 09/02/2018] [Indexed: 12/21/2022] Open
Abstract
Background Until now, there have been no objective criteria to determine the activity of chronic pulmonary aspergillosis (CPA). This study aims to analyze the correlation between serum level of IL-1B and the activity of CPA and to determine whether serum IL-1B could be used to assess the activity of CPA. Methods A total of 469 newly diagnosed CPA patients were enrolled. Correlation analysis in the whole subjects showed that only IL-1B level was associated with the activity of CPA. Then, 381 cases with factors significantly affecting IL-1B expression was excluded through multiple linear regression; the remaining 88 patients were divided into high IL-1B group and low IL-1B group, according to the median value of serum IL-1B, for subgroup analysis. A retrospective comparative analysis was subsequently performed between the two groups, including the clinical manifestation, microbiology and laboratory tests results, and imaging findings. We further investigated the relationship between IL-1B levels and CT characteristic which acted as the indicator of CPA activity, as well as changes in IL-1B level before and after surgery. Results For all patients, correlation analysis revealed that IL-1B level correlated with both cavitary diameter (P=0.035) and aspergilloma size (P<0.047) but not with the thickness of the cavity (P=0.479). In subgroup comparative analysis, CT characteristics suggested that high activity of CPA, such as cavitary (27/44 vs 13/44, P=0.003) and aspergilloma lesions (25/44 vs. 11/44, P<0.002), were more frequently found in high IL-1B group. The cavity diameter (P<0.001), aspergilloma size (P=0.006), and cavity wall thickness (P=0.023) were significantly different between the two groups. When Spearman correlation analysis was performed once again in subgroup, an even stronger relationship of serum IL-1B with the cavity diameter (Rs=0.501, P=0.002) and aspergilloma size (Rs=0.615, P=0.001) was observed. Interestingly, a significant reduction of IL-1B level was observed after successful resection of CPA lesions. Conclusion Higher level of serum IL-1B is associated with more severe cavitary and aspergilloma lesions, which are indicative of more active CPA. In addition, IL-1B level reduced accordingly after lesion resection. Measuring IL-1B level therefore could be served as a convenient method to monitor the activity of CPA and be a potential predictive/prognostic marker for treatment response.
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Affiliation(s)
- Mengling Zhan
- Tongji University School of Medicine, Shanghai 200092, China
| | - Benyong Xu
- Tongji University School of Medicine, Shanghai 200092, China
| | - Lan Zhao
- Department of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Bing Li
- Department of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Liyun Xu
- Department of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Qiuhong Sun
- Department of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Jun Zhang
- Division of Hematology, Oncology and Blood & Marrow Transplantation, Department of Internal Medicine, Holden Comprehensive Cancer Center, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA
| | - Zhemin Zhang
- Department of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
| | - Haiqing Chu
- Department of Respiratory Medicine, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai 200433, China
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25
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Güngör Ö, Sampaio-Maia B, Amorim A, Araujo R, Erturan Z. Determination of Azole Resistance and TR 34/L98H Mutations in Isolates of Aspergillus Section Fumigati from Turkish Cystic Fibrosis Patients. Mycopathologia 2018; 183:913-920. [PMID: 30187246 DOI: 10.1007/s11046-018-0297-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 08/24/2018] [Indexed: 02/05/2023]
Abstract
BACKGROUND Aspergillus fumigatus is the species section Fumigati most frequently isolated from the respiratory tract of cystic fibrosis (CF) patients. Recent studies suggest that mutations in the Cyp51 gene, particularly TR34/L98H, are responsible for azole resistance. OBJECTIVES AND METHODS The focus of this study was on section Fumigati isolates isolated from the respiratory tract samples of CF patients. More specifically, the goal was to detect A. fumigatus isolates, test their antifungal susceptibility to itraconazole, voriconazole and posaconazole, and finally determine the presence of TR34/L98H and other mutations in the isolates Cyp51A gene. RESULTS AND CONCLUSIONS A set of 31 isolates of Aspergillus section Fumigati were obtained from the sputum samples of 6 CF patients and subsequently identified to species level by microsatellite genotyping. All isolates were determined as A. fumigatus and involved 14 different genotypes. The minimal inhibitory concentrations to the three azoles were determined by the E-test method, and the Cyp51A gene was sequenced. One of the genotypes was found to be resistant to all azoles but no mutations were detected in the Cyp51A gene, especially the TR34/L98H mutation. Therefore, mutations in genes other than Cyp51A or other distinct mechanisms may be responsible for this reported multiazole resistance found in a Turkish CF patient.
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Affiliation(s)
- Özge Güngör
- Istanbul Medical Faculty, Department of Medical Microbiology, Istanbul University, 34093, Capa, Istanbul, Turkey.
| | - Benedita Sampaio-Maia
- Faculty of Dental Medicine, University of Porto, Porto, Portugal
- INEB, Instituto Nacional de Engenharia Biomédica da Universidade do Porto, Porto, Portugal
- i3S, Instituto de Investigação e Inovação em Saúde da Universidade do Porto, Porto, Portugal
| | - Antonio Amorim
- i3S, Instituto de Investigação e Inovação em Saúde da Universidade do Porto, Porto, Portugal
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto, Portugal
- Faculdade de Ciências, Universidade do Porto, Porto, Portugal
| | - Ricardo Araujo
- i3S, Instituto de Investigação e Inovação em Saúde da Universidade do Porto, Porto, Portugal
- Department of Medical Biotechnology, College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Zayre Erturan
- Istanbul Medical Faculty, Department of Medical Microbiology, Istanbul University, 34093, Capa, Istanbul, Turkey
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26
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Identification of 14-α-Lanosterol Demethylase (CYP51) in Scedosporium Species. Antimicrob Agents Chemother 2018; 62:AAC.02599-17. [PMID: 29891611 DOI: 10.1128/aac.02599-17] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Accepted: 05/01/2018] [Indexed: 11/20/2022] Open
Abstract
Scedosporium spp. cause infections (scedosporiosis) in both immunocompetent and immunocompromised individuals and may persistently colonize the respiratory tract in patients with cystic fibrosis (CF). They are less susceptible against azoles than are other molds, such as Aspergillus spp., suggesting the presence of resistance mechanisms. It can be hypothesized that the decreased susceptibility of Scedosporium spp. to azoles is also CYP51 dependent. Analysis of the Scedosporium apiospermum and Scedosporiumaurantiacum genomes revealed one CYP51 gene encoding the 14-α-lanosterol demethylase. This gene from 159 clinical or environmental Scedosporium isolates and three Lomentospora prolificans isolates has been sequenced and analyzed. The Scedosporium CYP51 protein clustered with the group of known CYP51B orthologues and showed species-specific polymorphisms. A tandem repeat in the 5' upstream region of Scedosporium CYP51 like that in Aspergillus fumigatus could not be detected. Species-specific amino acid alterations in CYP51 of Scedosporium boydii, Scedosporiumellipsoideum, Scedosporium dehoogii, and Scedosporiumminutisporum isolates were located at positions that have not been described as having an impact on azole susceptibility. In contrast, two of the three Sapiospermum-specific amino acid changes (Y136F and G464S) corresponded to respective mutations in A. fumigatus CYP51A at amino acid positions 121 and 448 (Y121F and G448S, respectively) that had been linked to azole resistance.
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Impact of Homologous Resistance Mutations from Pathogenic Yeast on Saccharomyces cerevisiae Lanosterol 14α-Demethylase. Antimicrob Agents Chemother 2018; 62:AAC.02242-17. [PMID: 29263059 DOI: 10.1128/aac.02242-17] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2017] [Accepted: 12/08/2017] [Indexed: 11/20/2022] Open
Abstract
Fungal infections frequently affect immunodeficient individuals and are estimated to kill 1.35 million people per annum. Azole antifungals target the membrane-bound cytochrome P450 monooxygenase lanosterol 14α-demethylase (CYP51; Erg11p). Mutations in CYP51 can render the widely used triazole drugs less effective. The Candida albicans CYP51 mutation G464S and the double mutation Y132F G464S (Y140F and G464S by Saccharomyces cerevisiae numbering) as well as the CYP51A G54E/R/W mutations of Aspergillus fumigatus (G73E/R/W by S. cerevisiae numbering) have been reproduced in a recombinant C-terminal hexahistidine-tagged version of S. cerevisiae CYP51 (ScErg11p6×His). Phenotypes and X-ray crystal structures were determined for the mutant enzymes. Liquid microdilution assays showed that the G464S mutation in ScErg11p6×His conferred no difference in the susceptibility of yeast to triazole drugs but in combination with the Y140F mutation gave a 4-fold reduction in susceptibility to the short-tailed triazole fluconazole. The ScErg11p6×His Y140F G464S mutant was unstable during purification and was not crystallized. The ScErg11p6×His G73E/R/W mutations conferred increased susceptibly to all triazoles tested in liquid microdilution assays. High-resolution X-ray crystal structures reveal two different conformations of the ligand itraconazole, including a previously unseen conformation, as well as interactions between the tail of this triazole and the E/W73 residue. This study shows that S. cerevisiae CYP51 adequately represents some but not all mutations in CYP51s of pathogenic fungi. Insight into the molecular mechanisms of resistance mutations in CYP51 will assist the development of inhibitors that will overcome antifungal resistance.
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Zacchino SA, Butassi E, Liberto MD, Raimondi M, Postigo A, Sortino M. Plant phenolics and terpenoids as adjuvants of antibacterial and antifungal drugs. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2017; 37:27-48. [PMID: 29174958 DOI: 10.1016/j.phymed.2017.10.018] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 10/30/2017] [Indexed: 05/27/2023]
Abstract
BACKGROUND The intensive use of antibacterial and antifungal drugs has dramatically increased the microbial resistance and has led to a higher number of difficult-to-eradicate infections. Combination therapy with two or more antimicrobial drugs has emerged some years ago to overcome the issue, but it has proven to be not completely effective. Natural secondary metabolites of MW ≤ 500 represent promising adjuvants for antimicrobials and have been the object of several researches that have increased in the last two decades. PURPOSE The purpose of this Review is to do a literature search of the natural compounds that showed high enhancing capacity of antibacterials' and antifungals' effects against planktonic bacteria and fungi and to analyze which are the natural products most used in combination with a focus on polyphenols and terpenoids. RESULTS One hundred of papers were collected for reviewing. Fifty six (56) of them deal with combinations of low MW natural products with antibacterial drugs against planktonic bacteria and forty four (44) on natural products with antifungal drugs against planktonic fungi. Of the antibacterial adjuvants, 41 (73%) were either polyphenols (27; 48%) or terpenes (14; 25%). The remaining 15 papers (27%), deal with different class of natural products. Since most natural potentiators belong to the terpene or phenolic structural types, a more detailed description of the works dealing with these type of compounds is provided here. Bacterial and fungal resistance mechanisms, the modes of action of the main classes of antibacterial and antifungal drugs and the methodologies most used to assess the type of interactions in the combinations were included in the Review too. CONCLUSIONS AND PERSPECTIVES Several promising results on the potentiation effects of antifungals' and antibacterials' activities by low MW natural products mainly on polyphenols and terpenes were reported in the literature and, in spite of that most works included only in vitro assays, this knowledge opens a wide range of possibilities for the combination antimicrobial therapy. Further research including in vivo assays and clinical trials are required to determine the relevance of these antimicrobial enhancers in the clinical area and should be the focus of future studies in order to develop new antimicrobial combination agents that overpass the drawbacks of the existing antibiotics and antifungals in clinical use.
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Affiliation(s)
- Susana A Zacchino
- Área Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina.
| | - Estefania Butassi
- Área Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Melina Di Liberto
- Área Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Marcela Raimondi
- Area Microbiología, Facultad de Cs. Médicas, Universidad Nacional de Rosario, Santa Fe 3100, Rosario 2000, Argentina
| | - Agustina Postigo
- Área Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Maximiliano Sortino
- Área Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina; Área Micología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
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Development and Validation of a High-Resolution Melting Assay To Detect Azole Resistance in Aspergillus fumigatus. Antimicrob Agents Chemother 2017; 61:AAC.01083-17. [PMID: 28893791 DOI: 10.1128/aac.01083-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2017] [Accepted: 09/03/2017] [Indexed: 01/04/2023] Open
Abstract
The global emergence of azole-resistant Aspergillus fumigatus strains is a growing public health concern. Different patterns of azole resistance are linked to mutations in cyp51A Therefore, accurate characterization of the mechanisms underlying azole resistance is critical to guide selection of the most appropriate antifungal agent for patients with aspergillosis. This study describes a new sequencing-free molecular screening tool for early detection of the most frequent mutations known to be associated with azole resistance in A. fumigatus PCRs targeting cyp51A mutations at positions G54, Y121, G448, and M220 and targeting different tandem repeats (TRs) in the promoter region were designed. All PCRs were performed simultaneously, using the same cycling conditions. Amplicons were then distinguished using a high-resolution melting assay. For standardization, 30 well-characterized azole-resistant A. fumigatus strains were used, yielding melting curve clusters for different resistance mechanisms for each target and allowing detection of the most frequent azole resistance mutations, i.e., G54E, G54V, G54R, G54W, Y121F, M220V, M220I, M220T, M220K, and G448S, and the tandem repeats TR34, TR46, and TR53 Validation of the method was performed using a blind panel of 80 A. fumigatus azole-susceptible or azole-resistant strains. All strains included in the blind panel were properly classified as susceptible or resistant with the developed method. The implementation of this screening method can reduce the time needed for the detection of azole-resistant A. fumigatus isolates and therefore facilitate selection of the best antifungal therapy in patients with aspergillosis.
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Denardi LB, Keller JT, de Azevedo MI, Oliveira V, Piasentin FB, Severo CB, Santurio JM, Alves SH. Comparison Between Etest and Broth Microdilution Methods for Testing Itraconazole-Resistant Aspergillus fumigatus Susceptibility to Antifungal Combinations. Mycopathologia 2017; 183:359-370. [PMID: 28994001 DOI: 10.1007/s11046-017-0208-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 10/02/2017] [Indexed: 11/30/2022]
Abstract
The checkerboard broth microdilution assay (BMD) is the most frequently used method for the in vitro evaluation of drug combinations. However, its use to evaluate the effect of antifungal drugs on filamentous fungi is sometimes associated with endpoint-reading difficulties, and different degrees of interaction are assigned to the same drug combination. We evaluated combinations of the azoles, itraconazole, posaconazole, and voriconazole, with the echinocandins, anidulafungin, caspofungin, and micafungin, against 15 itraconazole-resistant Aspergillus fumigatus clinical strains via the checkerboard BMD and Etest assay. Readings after 24 and 48 h, considering the two reading endpoints, the minimum inhibitory concentration (MIC) and minimum effective concentration (MEC), were performed for both methods. Our results showed that the correlation coefficients between the BMD and Etest methods were quite diverse to the drug combinations tested. The highest correlation coefficients of the Etest with the BMD assays (MEC and MIC reading) were the Etest-MIC reading at 24 h and the Etest-MEC reading at 48 h. Improvements in experimental conditions may increase the correlation between the two methods and ensure that Etest assay can be safely used in the evaluation of antifungal combinations against Aspergillus species.
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Affiliation(s)
- Laura Bedin Denardi
- Postgraduate Program in Pharmaceutical Sciences, Health Sciences Center, Federal University of Santa Maria, Santa Maria, RS, 97105-900, Brazil.
- Mycological Research Laboratory, Federal University of Santa Maria, UFSM, Santa Maria, RS, Brazil.
| | - Jéssica Tairine Keller
- Postgraduate Program in Pharmaceutical Sciences, Health Sciences Center, Federal University of Santa Maria, Santa Maria, RS, 97105-900, Brazil
- Mycological Research Laboratory, Federal University of Santa Maria, UFSM, Santa Maria, RS, Brazil
| | - Maria Isabel de Azevedo
- Postgraduate Program in Pharmacology, Health Sciences Center, Federal University of Santa Maria (UFSM), Santa Maria, RS, Brazil
- Mycological Research Laboratory, Federal University of Santa Maria, UFSM, Santa Maria, RS, Brazil
| | - Vanessa Oliveira
- Mycological Research Laboratory, Federal University of Santa Maria, UFSM, Santa Maria, RS, Brazil
| | - Fernanda Baldissera Piasentin
- Postgraduate Program in Pharmaceutical Sciences, Health Sciences Center, Federal University of Santa Maria, Santa Maria, RS, 97105-900, Brazil
- Mycological Research Laboratory, Federal University of Santa Maria, UFSM, Santa Maria, RS, Brazil
| | | | - Janio Morais Santurio
- Postgraduate Program in Pharmacology, Health Sciences Center, Federal University of Santa Maria (UFSM), Santa Maria, RS, Brazil
- Mycological Research Laboratory, Federal University of Santa Maria, UFSM, Santa Maria, RS, Brazil
| | - Sydney Hartz Alves
- Postgraduate Program in Pharmaceutical Sciences, Health Sciences Center, Federal University of Santa Maria, Santa Maria, RS, 97105-900, Brazil
- Mycological Research Laboratory, Federal University of Santa Maria, UFSM, Santa Maria, RS, Brazil
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Viegas C, Faria T, Caetano LA, Carolino E, Gomes AQ, Viegas S. Aspergillus spp. prevalence in different Portuguese occupational environments: What is the real scenario in high load settings? JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HYGIENE 2017; 14:771-785. [PMID: 28609213 DOI: 10.1080/15459624.2017.1334901] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The genus Aspergillus is one of the most prevalent regarding fungi in several highly contaminated occupational environments. The goal of the current study was to assess the prevalence of Aspergillus spp. in different settings, focusing on those where a higher load of fungal contamination is expected according to the European Agency for Safety and Health at Work. A specific protocol to ensure a more accurate assessment of the exposure to Aspergillus spp. is proposed aimed at allowing a detailed risk characterization and management. Two wastewater treatment plants, one wastewater elevation plant, four waste treatment plants, three cork industries, five slaughter houses, four feed industries, one poultry pavilion, and two swineries, all located in the outskirts of Lisbon, were assessed. In total, 125 air samples and 125 surface samples were collected and analysed by culture-based methods. Real-time polymerase chain reaction was performed to detect fungal presence in 100 samples, targeting the Aspergillus sections Circumdati, Flavi, and Fumigati. The highest prevalence of Aspergillus spp. was found in wastewater treatment plants (69.3%; 31.1%), waste treatment plants (34.8%; 73.6%), and poultry feed industry (6.3%; 26.1%), in air and surfaces, respectively. Aspergillus spp. was also prevalent in cork industry (0.9%; 23.4%), slaughter houses (1.6%; 17.7%), and swineries (7.4%; 9.5%), in air and surfaces, respectively. The Aspergillus sections more prevalent in the air and surfaces of all the assessed settings were the Nigri section (47.46%; 44.71%, respectively), followed by Fumigati (22.28%; 27.97%, respectively) and Flavi (10.78%; 11.45%, respectively) sections. Aspergillus section Fumigati was successfully amplified by qPCR in 18 sampling sites where the presence of this fungal species had not been identified by conventional methods. It should be highlighted that the occupational exposure burden is due not only to the Aspergillus load, but also to the toxigenic potential of this genus. Based on our results, a protocol relied in the application of conventional and molecular methods in parallel is herein suggested aimed at allowing a better risk characterization and management.
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Affiliation(s)
- Carla Viegas
- a GIAS, ESTeSL - Escola Superior de Tecnologia da Saúde de Lisboa , Instituto Politécnico de Lisboa , Lisbon , Portugal
- b Centro de Investigação em Saúde Pública Escola Nacional de Saúde Pública , Universidade Nova de Lisboa , Lisbon , Portugal
| | - Tiago Faria
- a GIAS, ESTeSL - Escola Superior de Tecnologia da Saúde de Lisboa , Instituto Politécnico de Lisboa , Lisbon , Portugal
| | - Liliana Aranha Caetano
- a GIAS, ESTeSL - Escola Superior de Tecnologia da Saúde de Lisboa , Instituto Politécnico de Lisboa , Lisbon , Portugal
- c Research Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy , University of Lisbon , Lisbon , Portugal
| | - Elisabete Carolino
- a GIAS, ESTeSL - Escola Superior de Tecnologia da Saúde de Lisboa , Instituto Politécnico de Lisboa , Lisbon , Portugal
| | - Anita Quintal Gomes
- a GIAS, ESTeSL - Escola Superior de Tecnologia da Saúde de Lisboa , Instituto Politécnico de Lisboa , Lisbon , Portugal
- d Instituto de Medicina Molecular , Faculdade de Medicina de Lisboa , Lisboa , Portugal
| | - Susana Viegas
- a GIAS, ESTeSL - Escola Superior de Tecnologia da Saúde de Lisboa , Instituto Politécnico de Lisboa , Lisbon , Portugal
- b Centro de Investigação em Saúde Pública Escola Nacional de Saúde Pública , Universidade Nova de Lisboa , Lisbon , Portugal
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In Vivo Efficacy of Liposomal Amphotericin B against Wild-Type and Azole-Resistant Aspergillus fumigatus Isolates in Two Different Immunosuppression Models of Invasive Aspergillosis. Antimicrob Agents Chemother 2017; 61:AAC.02479-16. [PMID: 28416540 DOI: 10.1128/aac.02479-16] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 04/07/2017] [Indexed: 01/06/2023] Open
Abstract
Using an immunocompetent murine model of invasive aspergillosis (IA), we previously reported that the efficacy of liposomal amphotericin B (L-AmB) (Ambisome) is not hampered by the presence of azole resistance mutations in Aspergillus fumigatus (S. Seyedmousavi, W. J. G. Melchers, J. W. Mouton, and P. E. Verweij, Antimicrob Agents Chemother 57:1866-1871, 2013, https://doi.org/10.1128/AAC.02226-12). We here investigated the role of immune suppression, i.e., neutropenia and steroid treatment, in L-AmB efficacy in mice infected with wild-type (WT) A. fumigatus and with azole-resistant A. fumigatus harboring a TR34/L98H mutation in the cyp-51A gene. Survival of treated animals at day 14 in both immunosuppressed models was significantly better than that of nontreated controls. A dose-response relationship was observed that was independent of the azole-resistant mechanism and the immunosuppression method used. In the neutropenic model, 100% survival was reached at an L-AmB dose of 16 mg/kg of body weight for the WT strain and the TR34/L98H isolate. In the steroid-treated group, 90.9% survival and 100% survival were achieved for the WT isolate and the TR34/L98H isolate with an L-AmB dose of 16 mg/kg, respectively. The 50% effective dose (ED50) was 1.40 mg/kg (95% confidence interval [CI], 0.66 to 3.00 mg/kg) for the WT isolate and 1.92 mg/kg (95% CI, 0.60 to 6.17 mg/kg) for the TR34/L98H isolate in the neutropenic model and was 2.40 mg/kg (95% CI, 1.93 to 2.97 mg/kg) for the WT isolate and 2.56 mg/kg (95% CI, 1.43 to 4.56 mg/kg) for the TR34/L98H isolate in the steroid-treated group. Overall, there were no significant differences between the two different immunosuppressed conditions in the efficacy of L-AmB against the wild-type and azole-resistant isolates (P > 0.9). However, the required L-AmB exposure was significantly higher than that seen in the immunocompetent model.
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Zhang M, Feng CL, Chen F, He Q, Su X, Shi Y. Triazole Resistance in Aspergillus fumigatus Clinical Isolates Obtained in Nanjing, China. Chin Med J (Engl) 2017; 130:665-668. [PMID: 28303848 PMCID: PMC5358415 DOI: 10.4103/0366-6999.201609] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND During the past decades, the incidence of invasive aspergillosis (IA) caused by Aspergillus fumigatus has increased dramatically. The aims of this study were to investigate the susceptibility of clinical isolates of A. fumigatus to triazole and the underlying cyp51A mutations in triazole-resistant A. fumigatus. METHODS A total of 126 A. fumigatus clinical isolates from 126 patients with proven or probable IA were obtained from four large tertiary hospitals in Nanjing, China, between August 2012 and July 2015. The determination of minimal inhibitory concentrations (MICs) for itraconazole, voriconazole, and posaconazole was performed by broth microdilution according to the European Committee on Antimicrobial Susceptibility Testing reference method. RESULTS A total of 4 A. fumigatus isolates (3.17%) were confirmed to be itraconazole resistant, with MICs of ≥8 mg/L, and one isolate (0.8%) was confirmed to be voriconazole resistant and posaconazole resistant, with MICs of 4 mg/L and 0.5 mg/L, respectively. We found that two of the 4 isolates of triazole-resistant A. fumigatus had the L98H amino acid substitution in combination with a 34-base pair tandem repeat in the promoter region, one isolate had an M220I mutation, and another itraconazole-resistant isolate did not have a substitution in the cyp51A gene. CONCLUSIONS This study shows that triazole-resistant A. fumigatus clinical isolates are present in Nanjing, China, which is a new challenge to the clinical management of IA.
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Affiliation(s)
- Ming Zhang
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Chun-Lai Feng
- Department of Respiratory Medicine, The Third Affiliated Hospital of Soochow University, Changzhou, Jiangsu 213003, China
| | - Fei Chen
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Qian He
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Xin Su
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
| | - Yi Shi
- Department of Respiratory and Critical Care Medicine, Jinling Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210002, China
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Soberón JR, Sgariglia MA, Pastoriza AC, Soruco EM, Jäger SN, Labadie GR, Sampietro DA, Vattuone MA. Antifungal activity and cytotoxicity of extracts and triterpenoid saponins obtained from the aerial parts of Anagallis arvensis L. JOURNAL OF ETHNOPHARMACOLOGY 2017; 203:233-240. [PMID: 28389355 DOI: 10.1016/j.jep.2017.03.056] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Revised: 03/22/2017] [Accepted: 03/31/2017] [Indexed: 06/07/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Anagallis arvensis L. (Primulaceae) is used in argentinean northwestern traditional medicine to treat fungal infections. We are reporting the isolation and identification of compounds with antifungal activity against human pathogenic yeast Candida albicans, and toxicity evaluation. AIM OF THE STUDY to study the antifungal activity of extracts and purified compounds obtained form A. arvensis aerial parts, alone and in combinations with fluconazole (FLU), and to study the toxicity of the active compounds. MATERIALS AND METHODS Disk diffusion assays were used to perform an activity-guided isolation of antifungal compounds from the aerial parts of A. arvensis. Broth dilution checkerboard and viable cell count assays were employed to determine the effects of samples and combinations of FLU + samples against Candida albicans. The chemical structures of active compounds were elucidated by spectroscopic analysis. Genotoxic and haemolytic effects of the isolated compounds were determined. RESULTS Four triterpenoid saponins (1-4) were identified. Anagallisin C (AnC), exerted the highest inhibitory activity among the assayed compounds against C. albicans reference strain (ATCC 10231), with MIC-0 =1µg/mL. The Fractional Inhibitory Concentration Index (FICI=0.129) indicated a synergistic effect between AnC (0.125µg/mL) and FLU (0.031µg/mL) against C. albicans ATCC 10231. AnC inhibited C. albicans 12-99 FLU resistant strain (MIC-0 =1µg/mL), and the FICI=0.188 indicated a synergistic effect between AnC (0.125µg/mL) and fluconazole (16µg/mL). The combination AnC+ FLU exerted fungicidal activity against both C. albicans strains. AnC exerted inhibitory activity against C. albicans ATCC 10231 sessile cells (MIC50=0.5µg/mL and MIC80=1µg/mL) and against C. albicans 12-99 sessile cells (MIC50=0.75µg/mL and MIC80=1.25µg/mL). AnC exerted haemolytic effect against human red blood cells at 15µg/mL and did not exerted genotoxic effect on Bacillus subtilis rec strains. CONCLUSIONS The antifungal activity and lack of genotoxic effects of AnC give support to the traditional use of A. arvensis as antifungal and makes AnC a compound of interest to expand the available antifungal drugs.
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Affiliation(s)
- José R Soberón
- Cátedra de Fitoquímica, Instituto de Estudios Farmacológicos "Dr. A.R. Sampietro", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, C1425FQB Ciudad Autónoma de Buenos Aires, Argentina.
| | - Melina A Sgariglia
- Cátedra de Fitoquímica, Instituto de Estudios Farmacológicos "Dr. A.R. Sampietro", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, C1425FQB Ciudad Autónoma de Buenos Aires, Argentina
| | - Ana C Pastoriza
- Cátedra de Fitoquímica, Instituto de Estudios Farmacológicos "Dr. A.R. Sampietro", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, T4000INI San Miguel de Tucumán, Tucumán, Argentina
| | - Estela M Soruco
- Cátedra de Fitoquímica, Instituto de Estudios Farmacológicos "Dr. A.R. Sampietro", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, T4000INI San Miguel de Tucumán, Tucumán, Argentina
| | - Sebastián N Jäger
- Instituto de Química Rosario, UNR, CONICET, Suipacha 531, S2002LRK Rosario, Argentina
| | - Guillermo R Labadie
- Instituto de Química Rosario, UNR, CONICET, Suipacha 531, S2002LRK Rosario, Argentina; Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, S2002LRK Rosario, Argentina
| | - Diego A Sampietro
- Cátedra de Fitoquímica, Instituto de Estudios Farmacológicos "Dr. A.R. Sampietro", Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, Ayacucho 471, T4000INI San Miguel de Tucumán, Tucumán, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, C1425FQB Ciudad Autónoma de Buenos Aires, Argentina
| | - Marta A Vattuone
- Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Godoy Cruz 2290, C1425FQB Ciudad Autónoma de Buenos Aires, Argentina
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Paulussen C, Hallsworth JE, Álvarez‐Pérez S, Nierman WC, Hamill PG, Blain D, Rediers H, Lievens B. Ecology of aspergillosis: insights into the pathogenic potency of Aspergillus fumigatus and some other Aspergillus species. Microb Biotechnol 2017; 10:296-322. [PMID: 27273822 PMCID: PMC5328810 DOI: 10.1111/1751-7915.12367] [Citation(s) in RCA: 179] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Revised: 04/08/2016] [Accepted: 04/18/2016] [Indexed: 01/26/2023] Open
Abstract
Fungi of the genus Aspergillus are widespread in the environment. Some Aspergillus species, most commonly Aspergillus fumigatus, may lead to a variety of allergic reactions and life-threatening systemic infections in humans. Invasive aspergillosis occurs primarily in patients with severe immunodeficiency, and has dramatically increased in recent years. There are several factors at play that contribute to aspergillosis, including both fungus and host-related factors such as strain virulence and host pulmonary structure/immune status, respectively. The environmental tenacity of Aspergilllus, its dominance in diverse microbial communities/habitats, and its ability to navigate the ecophysiological and biophysical challenges of host infection are attributable, in large part, to a robust stress-tolerance biology and exceptional capacity to generate cell-available energy. Aspects of its stress metabolism, ecology, interactions with diverse animal hosts, clinical presentations and treatment regimens have been well-studied over the past years. Here, we synthesize these findings in relation to the way in which some Aspergillus species have become successful opportunistic pathogens of human- and other animal hosts. We focus on the biophysical capabilities of Aspergillus pathogens, key aspects of their ecophysiology and the flexibility to undergo a sexual cycle or form cryptic species. Additionally, recent advances in diagnosis of the disease are discussed as well as implications in relation to questions that have yet to be resolved.
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Affiliation(s)
- Caroline Paulussen
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM)Department of Microbial and Molecular Systems (M2S)KU LeuvenCampus De NayerSint‐Katelijne‐WaverB‐2860Belgium
| | - John E. Hallsworth
- Institute for Global Food SecuritySchool of Biological SciencesMedical Biology CentreQueen's University BelfastBelfastBT9 7BLUK
| | - Sergio Álvarez‐Pérez
- Faculty of Veterinary MedicineDepartment of Animal HealthUniversidad Complutense de MadridMadridE‐28040Spain
| | | | - Philip G. Hamill
- Institute for Global Food SecuritySchool of Biological SciencesMedical Biology CentreQueen's University BelfastBelfastBT9 7BLUK
| | - David Blain
- Institute for Global Food SecuritySchool of Biological SciencesMedical Biology CentreQueen's University BelfastBelfastBT9 7BLUK
| | - Hans Rediers
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM)Department of Microbial and Molecular Systems (M2S)KU LeuvenCampus De NayerSint‐Katelijne‐WaverB‐2860Belgium
| | - Bart Lievens
- Laboratory for Process Microbial Ecology and Bioinspirational Management (PME&BIM)Department of Microbial and Molecular Systems (M2S)KU LeuvenCampus De NayerSint‐Katelijne‐WaverB‐2860Belgium
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Gonçalves SS. Global Aspects of Triazole Resistance in Aspergillus fumigatus with Focus on Latin American Countries. J Fungi (Basel) 2017; 3:jof3010005. [PMID: 29371524 PMCID: PMC5715964 DOI: 10.3390/jof3010005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 02/06/2017] [Accepted: 02/07/2017] [Indexed: 12/30/2022] Open
Abstract
Azole resistance in Aspergillus has emerged as an escalating problem in health care, and it has been detected in patients exposed, or not, to these drugs. It is known that azole antifungals are widely applied not only in clinical treatments for fungal infections, but also as agricultural fungicides, resulting in a significant threat for human health. Although the number of cases of azole-resistant aspergillosis is still limited, various resistance mechanisms are described from clinical and environmental isolates. These mechanisms consist mainly of alterations in the target of azole action (CYP51A gene)—specifically on TR34/L98H and TR46/Y121F/T289A, which are responsible for over 90% of resistance cases. This review summarizes the epidemiology, management, and extension of azole resistance in A. fumigatus worldwide and its potential impact in Latin American countries, emphasizing its relevance to clinical practice.
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Affiliation(s)
- Sarah Santos Gonçalves
- Center for Research in Medical Mycology, Department of Pathology, Universidade Federal do Espírito Santo-UFES, Av. Marechal Campos, 1468, Maruípe CEP 29.040-090, Vitória-ES, Brazil.
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Dhingra S, Cramer RA. Regulation of Sterol Biosynthesis in the Human Fungal Pathogen Aspergillus fumigatus: Opportunities for Therapeutic Development. Front Microbiol 2017; 8:92. [PMID: 28203225 PMCID: PMC5285346 DOI: 10.3389/fmicb.2017.00092] [Citation(s) in RCA: 53] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 01/13/2017] [Indexed: 12/29/2022] Open
Abstract
Sterols are a major component of eukaryotic cell membranes. For human fungal infections caused by the filamentous fungus Aspergillus fumigatus, antifungal drugs that target sterol biosynthesis and/or function remain the standard of care. Yet, an understanding of A. fumigatus sterol biosynthesis regulatory mechanisms remains an under developed therapeutic target. The critical role of sterol biosynthesis regulation and its interactions with clinically relevant azole drugs is highlighted by the basic helix loop helix (bHLH) class of transcription factors known as Sterol Regulatory Element Binding Proteins (SREBPs). SREBPs regulate transcription of key ergosterol biosynthesis genes in fungi including A. fumigatus. In addition, other emerging regulatory pathways and target genes involved in sterol biosynthesis and drug interactions provide additional opportunities including the unfolded protein response, iron responsive transcriptional networks, and chaperone proteins such as Hsp90. Thus, targeting molecular pathways critical for sterol biosynthesis regulation presents an opportunity to improve therapeutic options for the collection of diseases termed aspergillosis. This mini-review summarizes our current understanding of sterol biosynthesis regulation with a focus on mechanisms of transcriptional regulation by the SREBP family of transcription factors.
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Affiliation(s)
- Sourabh Dhingra
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover NH, USA
| | - Robert A Cramer
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover NH, USA
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Abstract
Azole antifungal agents (eg, fluconazole and itraconazole) have been widely used to treat superficial fungal infections caused by dermatophytes and, unlike the allylamines (such as terbinafine and naftifine), have been associated with resistance development. Although many published manuscripts describe resistance to azoles among yeast and molds, reports describing resistance of dermatophytes are starting to appear. In this review, I discuss the mode of action of azole antifungals and mechanisms underlying their resistance compared with the allylamine class of compounds. Data from published and original studies were compared and summarized, and their clinical implications are discussed. In contrast to the cidal allylamines, static drugs such as azoles permit the occurrence of mutations in enzymes involved in ergosterol biosynthesis, and the ergosterol precursors accumulating as a consequence of azole action are not toxic. Azole antifungals, unlike allylamines, potentiate resistance development in dermatophytes.
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Yang YX, An MM, Jin YS, Chen HS. Chemical constituents from the rhizome of Polygonum paleaceum and their antifungal activity. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2017; 19:47-52. [PMID: 27309618 DOI: 10.1080/10286020.2016.1196672] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A new compounds neopaleaceolactoside (1), along with nine known compounds phyllocoumarin (2), quercetin (3), quercitrin (4), quercetin-3-methyl ether (5), vincetoxicoside B (6), isoquercitrin (7), kaempferol (8), (-)-epicatechin (9), and chlorogenic acid (10), was isolated from Polygonum paleaceum Wall. Their chemical structures were established based on one-dimensional and two-dimensional nuclear magnetic resonance techniques, mass spectrometry and by comparison with spectroscopic data reported. Some selected compounds were screened for their antifungal activity. Quercetin (3), vincetoxicoside B (6), kaempferol (8), and (-)-epicatechin (9) showed synergistic antifungal activities with the FICI values <0.5. A preliminary structure-activity relationship could be observed that free 3-OH in the structure of flavonoids was important for synergistic antifungal activity.
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Affiliation(s)
- Yi-Xi Yang
- a School of Pharmacy , Second Military Medical University , Shanghai 200433 , China
| | - Mao-Mao An
- b School of Medicine , Tongji University , Shanghai 200092 , China
| | - Yong-Sheng Jin
- a School of Pharmacy , Second Military Medical University , Shanghai 200433 , China
| | - Hai-Sheng Chen
- a School of Pharmacy , Second Military Medical University , Shanghai 200433 , China
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Pharmacodynamics of Voriconazole against Wild-Type and Azole-Resistant Aspergillus flavus Isolates in a Nonneutropenic Murine Model of Disseminated Aspergillosis. Antimicrob Agents Chemother 2016; 61:AAC.01491-16. [PMID: 27821453 DOI: 10.1128/aac.01491-16] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Accepted: 11/01/2016] [Indexed: 11/20/2022] Open
Abstract
Invasive aspergillosis (IA) due to Aspergillus flavus is associated with high mortality. Although voriconazole (VRC) is widely recommended as the first-line treatment for IA, emergence of azole resistance in Aspergillus spp. is translating to treatment failure. We evaluated the efficacy of voriconazole in a nonneutropenic murine model of disseminated A. flavus infection using two voriconazole-resistant isolates (one harboring the Y319H substitution in the cyp51C gene) and two wild-type isolates without mutations. All isolates exhibited a dose-response relationship, and voriconazole treatment improved mouse survival in a dose-dependent manner. At 40 mg/kg of body weight, 100% efficacy was observed for 1 susceptible isolate and 1 resistant isolate (with mutation), whereas for another susceptible isolate and resistant isolate (without mutation), survival rates were 81% and 72%, respectively. The Hill equation with a variable slope fitted the relationship between the area under the concentration-time curve (AUC)/MIC ratio and 14-day survival well for each strain. An F test showed the 50% effective doses to be significantly different from each other (P = 0.0023). However, contrary to expectation, there was a significant difference in exposure-response relationships between strains, and it appeared that the susceptible strains required a relatively higher exposure than the resistant ones to result in the same treatment effect, the 50% effective pharmacokinetic/pharmacodynamic (PK/PD) index (EI50) required being negatively and log-linearly related to the MIC (P = 0.04). We conclude that the efficacy of voriconazole depended on drug exposure and the voriconazole MIC of the isolates, but lower exposures are required for strains with higher MICs. These findings may have profound significance in clinical practice with respect to dosing and drug choice.
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Screening and Characterization of a Non-cyp51A Mutation in an Aspergillus fumigatus cox10 Strain Conferring Azole Resistance. Antimicrob Agents Chemother 2016; 61:AAC.02101-16. [PMID: 27799210 DOI: 10.1128/aac.02101-16] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 10/18/2016] [Indexed: 12/14/2022] Open
Abstract
The rapid and global emergence of azole resistance in the human pathogen Aspergillus fumigatus has drawn attention. Thus, a thorough understanding of its mechanisms of drug resistance requires extensive exploration. In this study, we found that the loss of the putative calcium-dependent protein-encoding gene algA causes an increased frequency of azole-resistant A. fumigatus isolates. In contrast to previously identified azole-resistant isolates related to cyp51A mutations, only one isolate carries a point mutation in cyp51A (F219L mutation) among 105 independent stable azole-resistant isolates. Through next-generation sequencing (NGS), we successfully identified a new mutation (R243Q substitution) conferring azole resistance in the putative A. fumigatus farnesyltransferase Cox10 (AfCox10) (AFUB_065450). High-performance liquid chromatography (HPLC) analysis verified that the decreased absorption of itraconazole in related Afcox10 mutants is the primary reason for itraconazole resistance. Moreover, a complementation experiment by reengineering the mutation in a parental wild-type background strain demonstrated that both the F219L and R243Q mutations contribute to itraconazole resistance in an algA-independent manner. These data collectively suggest that the loss of algA results in an increased frequency of azole-resistant isolates with a non-cyp51A mutation. Our findings indicate that there are many unexplored non-cyp51A mutations conferring azole resistance in A. fumigatus and that algA defects make it possible to isolate drug-resistant alleles. In addition, our study suggests that genome-wide sequencing combined with alignment comparison analysis is an efficient approach to identify the contribution of single nucleotide polymorphism (SNP) diversity to drug resistance.
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Gu X, Xue W, Yin Y, Liu H, Li S, Sun X. The Hsp90 Co-chaperones Sti1, Aha1, and P23 Regulate Adaptive Responses to Antifungal Azoles. Front Microbiol 2016; 7:1571. [PMID: 27761133 PMCID: PMC5050212 DOI: 10.3389/fmicb.2016.01571] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/20/2016] [Indexed: 12/26/2022] Open
Abstract
Heat Shock Protein 90 (Hsp90) is essential for tumor progression in humans and drug resistance in fungi. However, the roles of its many co-chaperones in antifungal resistance are unknown. In this study, by susceptibility test of Neurospora crassa mutants lacking each of 18 Hsp90/Calcineurin system member genes (including 8 Hsp90 co-chaperone genes) to antifungal drugs and other stresses, we demonstrate that the Hsp90 co-chaperones Sti1 (Hop1 in yeast), Aha1, and P23 (Sba1 in yeast) were required for the basal resistance to antifungal azoles and heat stress. Deletion of any of them resulted in hypersensitivity to azoles and heat. Liquid chromatography-mass spectrometry (LC-MS) analysis showed that the toxic sterols eburicol and 14α-methyl-3,6-diol were significantly accumulated in the sti1 and p23 deletion mutants after ketoconazole treatment, which has been shown before to led to cell membrane stress. At the transcriptional level, Aha1, Sti1, and P23 positively regulate responses to ketoconazole stress by erg11 and erg6, key genes in the ergosterol biosynthetic pathway. Aha1, Sti1, and P23 are highly conserved in fungi, and sti1 and p23 deletion also increased the susceptibility to azoles in Fusarium verticillioides. These results indicate that Hsp90-cochaperones Aha1, Sti1, and P23 are critical for the basal azole resistance and could be potential targets for developing new antifungal agents.
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Affiliation(s)
- Xiaokui Gu
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of SciencesBeijing, China; College of Life Sciences, University of Chinese Academy of SciencesBeijing, China
| | - Wei Xue
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of SciencesBeijing, China; College of Life Sciences, University of Chinese Academy of SciencesBeijing, China
| | - Yajing Yin
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of SciencesBeijing, China; College of Life Sciences, University of Chinese Academy of SciencesBeijing, China
| | - Hongwei Liu
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences Beijing, China
| | - Shaojie Li
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences Beijing, China
| | - Xianyun Sun
- State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences Beijing, China
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Denning DW, Cadranel J, Beigelman-Aubry C, Ader F, Chakrabarti A, Blot S, Ullmann AJ, Dimopoulos G, Lange C. Chronic pulmonary aspergillosis: rationale and clinical guidelines for diagnosis and management. Eur Respir J 2016; 47:45-68. [PMID: 26699723 DOI: 10.1183/13993003.00583-2015] [Citation(s) in RCA: 529] [Impact Index Per Article: 66.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Chronic pulmonary aspergillosis (CPA) is an uncommon and problematic pulmonary disease, complicating many other respiratory disorders, thought to affect ~240 000 people in Europe. The most common form of CPA is chronic cavitary pulmonary aspergillosis (CCPA), which untreated may progress to chronic fibrosing pulmonary aspergillosis. Less common manifestations include: Aspergillus nodule and single aspergilloma. All these entities are found in non-immunocompromised patients with prior or current lung disease. Subacute invasive pulmonary aspergillosis (formerly called chronic necrotising pulmonary aspergillosis) is a more rapidly progressive infection (<3 months) usually found in moderately immunocompromised patients, which should be managed as invasive aspergillosis. Few clinical guidelines have been previously proposed for either diagnosis or management of CPA. A group of experts convened to develop clinical, radiological and microbiological guidelines. The diagnosis of CPA requires a combination of characteristics: one or more cavities with or without a fungal ball present or nodules on thoracic imaging, direct evidence of Aspergillus infection (microscopy or culture from biopsy) or an immunological response to Aspergillus spp. and exclusion of alternative diagnoses, all present for at least 3 months. Aspergillus antibody (precipitins) is elevated in over 90% of patients. Surgical excision of simple aspergilloma is recommended, if technically possible, and preferably via video-assisted thoracic surgery technique. Long-term oral antifungal therapy is recommended for CCPA to improve overall health status and respiratory symptoms, arrest haemoptysis and prevent progression. Careful monitoring of azole serum concentrations, drug interactions and possible toxicities is recommended. Haemoptysis may be controlled with tranexamic acid and bronchial artery embolisation, rarely surgical resection, and may be a sign of therapeutic failure and/or antifungal resistance. Patients with single Aspergillus nodules only need antifungal therapy if not fully resected, but if multiple they may benefit from antifungal treatment, and require careful follow-up.
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Affiliation(s)
- David W Denning
- The National Aspergillosis Centre, University Hospital of South Manchester, The University of Manchester and the Manchester Academic Health Science Centre, Manchester, UK
| | - Jacques Cadranel
- Service de Pneumologie, AP-HP, Hôpital Tenon and Sorbonne Université, UPMC Univ Paris 06, Paris, France
| | | | - Florence Ader
- Dept of Infectious Diseases, Hospices Civils de Lyon, Lyon, France Centre International de Recherche en Infectiologie (CIRI), INSERM U1111, CNRS UMR5308, Lyon, France
| | - Arunaloke Chakrabarti
- Center of Advanced Research in Medical Mycology, Dept of Medical Microbiology, Postgraduate Institute of Medical Education & Research, Chandigarh, India
| | - Stijn Blot
- Dept of Internal Medicine, Ghent University, Ghent, Belgium Burns, Trauma and Critical Care Research Centre, The University of Queensland, Brisbane, Australia
| | - Andrew J Ullmann
- Dept of Internal Medicine II, Division of Infectious Diseases, University Hospital Würzburg, Julius-Maximilians-University, Würzburg, Germany
| | - George Dimopoulos
- Dept of Critical and Respiratory Care, University Hospital Attikon, Medical School, University of Athens, Athens, Greece
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Zhao Y, Garnaud C, Brenier-Pinchart MP, Thiébaut-Bertrand A, Saint-Raymond C, Camara B, Hamidfar R, Cognet O, Maubon D, Cornet M, Perlin DS. Direct Molecular Diagnosis of Aspergillosis and CYP51A Profiling from Respiratory Samples of French Patients. Front Microbiol 2016; 7:1164. [PMID: 27524978 PMCID: PMC4965478 DOI: 10.3389/fmicb.2016.01164] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Accepted: 07/13/2016] [Indexed: 11/21/2022] Open
Abstract
Background: Microbiological diagnosis of aspergillosis and triazole resistance is limited by poor culture yield. To better estimate this shortcoming, we compared culture and molecular detection of A. fumigatus in respiratory samples from French patients at risk for aspergillosis. Methods: A total of 97 respiratory samples including bronchoalveolar lavages (BAL), bronchial aspirates (BA), tracheal aspirates, sputa, pleural fluids, and lung biopsy were collected from 33 patients having invasive aspergillosis (n = 12), chronic pulmonary aspergillosis (n = 3), allergic bronchopulmonary aspergillosis (n = 7), or colonization (n = 11) and 28 controls. Each specimen was evaluated by culture, pan-Aspergillus qPCR, and CYP51A PCR and sequencing. Results: One A. flavus and 19 A. fumigatus with one multiazole resistant strain (5.3%) were cultured from 20 samples. Culture positivity was 62.5, 75, 42.9, and 15.8% in ABPA, CPA, IA, and colonized patients, respectively. Aspergillus detection rate was significantly higher by pan-Aspergillus qPCR than by culture in IA (90.5 vs. 42.9%; P < 0.05) and colonization group (73.7 vs. 15.8%; P < 0.05). The CYP51A PCR found one TR34/L98H along with 5 novel cyp51A mutations (4 non-synonymous and 1 promoter mutations), yet no association can be established currently between these novel mutations and azole resistance. The analysis of 11 matched pairs of BA and BAL samples found that 9/11 BA carried greater fungal load than BAL and CYP51A detection was more sensitive in BA than in BAL. Conclusion: Direct molecular detection of Aspergillus spp. and azole resistance markers are useful adjunct tools for comprehensive aspergillosis diagnosis. The observed superior diagnostic value of BAs to BAL fluids warrants more in-depth study.
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Affiliation(s)
- Yanan Zhao
- New Jersey Medical School, Public Health Research Institute, Rutgers Biomedical and Health Sciences Newark, NJ, USA
| | - Cécile Garnaud
- Laboratoire de Parasitologie-Mycologie, Institut de Biologie et Pathologie, Centre Hospitalier Universitaire Grenoble AlpesGrenoble, France; Laboratoire TIMC-IMAG-TheREx, UMR 5525 Centre National de la Recherche Scientifique, Université Grenoble AlpesGrenoble, France
| | - Marie-Pierre Brenier-Pinchart
- Laboratoire de Parasitologie-Mycologie, Institut de Biologie et Pathologie, Centre Hospitalier Universitaire Grenoble AlpesGrenoble, France; Institut Albert Bonniot, Centre National de la Recherche Scientifique UMR 5309, Institut National de la Santé et de la Recherche Médicale U1209, Université Grenoble-AlpesGrenoble, France
| | - Anne Thiébaut-Bertrand
- Laboratoire TIMC-IMAG-TheREx, UMR 5525 Centre National de la Recherche Scientifique, Université Grenoble AlpesGrenoble, France; Clinique Universitaire d'Hématologie, Centre Hospitalier Universitaire Grenoble AlpesGrenoble, France
| | - Christel Saint-Raymond
- Clinique Universitaire de Pneumologie, Centre Hospitalier Universitaire Grenoble Alpes Grenoble, France
| | - Boubou Camara
- Clinique Universitaire de Pneumologie, Centre Hospitalier Universitaire Grenoble Alpes Grenoble, France
| | - Rebecca Hamidfar
- Réanimation Médicale, Centre Hospitalier Universitaire Grenoble Alpes Grenoble, France
| | - Odile Cognet
- Laboratoire de Parasitologie-Mycologie, Institut de Biologie et Pathologie, Centre Hospitalier Universitaire Grenoble Alpes Grenoble, France
| | - Danièle Maubon
- Laboratoire de Parasitologie-Mycologie, Institut de Biologie et Pathologie, Centre Hospitalier Universitaire Grenoble AlpesGrenoble, France; Laboratoire TIMC-IMAG-TheREx, UMR 5525 Centre National de la Recherche Scientifique, Université Grenoble AlpesGrenoble, France
| | - Muriel Cornet
- Laboratoire de Parasitologie-Mycologie, Institut de Biologie et Pathologie, Centre Hospitalier Universitaire Grenoble AlpesGrenoble, France; Laboratoire TIMC-IMAG-TheREx, UMR 5525 Centre National de la Recherche Scientifique, Université Grenoble AlpesGrenoble, France
| | - David S Perlin
- New Jersey Medical School, Public Health Research Institute, Rutgers Biomedical and Health Sciences Newark, NJ, USA
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Hayes GE, Novak-Frazer L. Chronic Pulmonary Aspergillosis-Where Are We? and Where Are We Going? J Fungi (Basel) 2016; 2:jof2020018. [PMID: 29376935 PMCID: PMC5753080 DOI: 10.3390/jof2020018] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Revised: 05/19/2016] [Accepted: 06/01/2016] [Indexed: 02/06/2023] Open
Abstract
Chronic pulmonary aspergillosis (CPA) is estimated to affect 3 million people worldwide making it an under recognised, but significant health problem across the globe, conferring significant morbidity and mortality. With variable disease forms, high levels of associated respiratory co-morbidity, limited therapeutic options and prolonged treatment strategies, CPA is a challenging disease for both patients and healthcare professionals. CPA can mimic smear-negative tuberculosis (TB), pulmonary histoplasmosis or coccidioidomycosis. Cultures for Aspergillus are usually negative, however, the detection of Aspergillus IgG is a simple and sensitive test widely used in diagnosis. When a fungal ball/aspergilloma is visible radiologically, the diagnosis has been made late. Sometimes weight loss and fatigue are predominant symptoms; pyrexia is rare. Despite the efforts of the mycology community, and significant strides being taken in optimising the care of these patients, much remains to be learnt about this patient population, the disease itself and the best use of available therapies, with the development of new therapies being a key priority. Here, current knowledge and practices are reviewed, and areas of research priority highlighted.
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Affiliation(s)
- Gemma E Hayes
- The University of Manchester, Oxford Road, Manchester M13 9PL, UK.
- Manchester Academic Health Science Centre, 46 Grafton Street, Manchester M13 9NT, UK.
- National Aspergillosis Centre, 2nd Floor Education and Research Centre, University Hospital of South Manchester, Southmoor Road, Manchester M23 9LT, UK.
| | - Lilyann Novak-Frazer
- The University of Manchester, Oxford Road, Manchester M13 9PL, UK.
- Manchester Academic Health Science Centre, 46 Grafton Street, Manchester M13 9NT, UK.
- The University of Manchester, Manchester Academic Health Science Centre, 2nd Floor Education and Research Centre, University Hospital of South Manchester, Southmoor Road, Manchester M23 9LT, UK.
- Mycology Reference Centre, Manchester, 2nd Floor Education and Research Centre, University Hospital of South Manchester, Southmoor Road, Manchester M23 9LT, UK.
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Meneau I, Coste AT, Sanglard D. Identification ofAspergillus fumigatusmultidrug transporter genes and their potential involvement in antifungal resistance. Med Mycol 2016; 54:616-27. [DOI: 10.1093/mmy/myw005] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 01/13/2016] [Indexed: 01/11/2023] Open
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Fattahi A, Zaini F, Kordbacheh P, Rezaie S, Safara M, Fateh R, Farahyar S, Kanani A, Heidari M. Evaluation of mRNA Expression Levels of cyp51A and mdr1, Candidate Genes for Voriconazole Resistance in Aspergillus flavus. Jundishapur J Microbiol 2015; 8:e26990. [PMID: 26865941 PMCID: PMC4745269 DOI: 10.5812/jjm.26990] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Revised: 05/11/2015] [Accepted: 05/24/2015] [Indexed: 11/16/2022] Open
Abstract
Background: Voriconazole Resistance (VRC-R) in Aspergillus flavus isolates impacts the management of aspergillosis, since azoles are the first choice for prophylaxis and therapy. However, to the best of our knowledge, the mechanisms underlying voriconazole resistance are poorly understood. Objectives: The present study was designed to evaluate mRNA expression levels of cyp51A and mdr1 genes in voriconazole resistant A. flavus by a Real-Time Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) technique. Materials and Methods: Five A. flavus isolates with resistance to VRC were examined by a RT-PCR approach. Results: Four out of five isolates revealed cyp51A and mdr1 mRNA overexpression. Interestingly, the isolate, which was negative for cyp51A and mdr1 mRNA expression showed a high voriconazole Minimum Inhibitory Concentration (MIC). Furthermore, a computational-based analysis predicted that voriconazole resistance could be mediated through cooperation with a network protein interaction. Conclusions: Our experimental and in silico findings may provide new insight in the complex molecular pathways of drug resistance and also could assist design an efficient therapeutic strategy for aspergillosis treatment.
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Affiliation(s)
- Azam Fattahi
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Farideh Zaini
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Parivash Kordbacheh
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Sasan Rezaie
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Mahin Safara
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Roohollah Fateh
- Department of Microbiology and Immunology, Faculty of Medicine, Qom University of Medical Sciences, Qom, IR Iran
| | - Shirin Farahyar
- Department of Medical Mycology and Parasitology, Faculty of Medicine, Iran University of Medical Sciences, Tehran, IR Iran
| | - Ali Kanani
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR Iran
| | - Mansour Heidari
- Department of Medical Genetics, Tehran University of Medical Sciences, Tehran, IR Iran
- Exprerimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, IR Iran
- Corresponding author: Mansour Heidari, Experimental Medicine Research Center, Tehran University of Medical Sciences, Tehran, IR Iran. Tel/Fax: +98-218895 3005, E-mail:
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Favre-Godal Q, Dorsaz S, Queiroz EF, Marcourt L, Ebrahimi SN, Allard PM, Voinesco F, Hamburger M, Gupta MP, Gindro K, Sanglard D, Wolfender JL. Anti-Candida Cassane-Type Diterpenoids from the Root Bark of Swartzia simplex. JOURNAL OF NATURAL PRODUCTS 2015; 78:2994-3004. [PMID: 26654828 DOI: 10.1021/acs.jnatprod.5b00744] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A dichloromethane extract of the roots from the Panamanian plant Swartzia simplex exhibited a strong antifungal activity in a bioautography assay against a genetically modified hypersusceptible strain of Candida albicans. At-line HPLC activity based profiling of the crude extract enabled a precise localization of the antifungal compounds, and dereplication by UHPLC-HRESIMS indicated the presence of potentially new metabolites. Transposition of the HPLC reversed-phase analytical conditions to medium-pressure liquid chromatography (MPLC) allowed an efficient isolation of the major constituents. Minor compounds of interest were isolated from the MPLC fractions using semipreparative HPLC. Using this strategy, 14 diterpenes (1-14) were isolated, with seven (5-10, 14) being new antifungal natural products. The new structures were elucidated using NMR spectroscopy and HRESIMS analysis. The absolute configurations of some of the compounds were elucidated by electronic circular dichroism spectroscopy. The antifungal properties of these compounds were evaluated as their minimum inhibitory concentrations in a dilution assay against both hypersusceptible and wild-type strains of C. albicans and by assessment of their antibiofilm activities. The potential cytological effects on the ultrastructure of C. albicans of the antifungal compounds isolated were evaluated on thin sections by transmission electron microscopy.
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Affiliation(s)
- Quentin Favre-Godal
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne , 30 quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
| | - Stephane Dorsaz
- Institute of Microbiology, University of Lausanne and University Hospital Center , Rue du Bugnon 48, CH-1011 Lausanne, Switzerland
| | - Emerson F Queiroz
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne , 30 quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
| | - Laurence Marcourt
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne , 30 quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
| | - Samad N Ebrahimi
- Department of Phytochemistry, Medicinal Plants and Drugs Research Institute, Shahid Beheshti University , G. C., Evin, P.O. Box 19835-389, Tehran, Iran
| | - Pierre-Marie Allard
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne , 30 quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
| | - Francine Voinesco
- Agroscope, Institute for Plant Production Sciences (IPS), Mycology and Biotechnology , Route de Duiller 50, P.O. Box 1012, CH-1260 Nyon, Switzerland
| | - Matthias Hamburger
- Division of Pharmaceutical Biology, Department of Pharmaceutical Sciences, University of Basel , Klingelbergstrasse 50, CH-4056 Basel, Switzerland
| | - Mahabir P Gupta
- Center for Pharmacognostic Research on Panamanian Flora (CIFLORPAN), University of Panama , P.O. Box 0824-00172, Panama City, Panama
| | - Katia Gindro
- Agroscope, Institute for Plant Production Sciences (IPS), Mycology and Biotechnology , Route de Duiller 50, P.O. Box 1012, CH-1260 Nyon, Switzerland
| | - Dominique Sanglard
- Institute of Microbiology, University of Lausanne and University Hospital Center , Rue du Bugnon 48, CH-1011 Lausanne, Switzerland
| | - Jean-Luc Wolfender
- School of Pharmaceutical Sciences, EPGL, University of Geneva, University of Lausanne , 30 quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland
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Abstract
Rapid, accurate diagnostic laboratory tests are needed to improve clinical outcomes of invasive fungal disease (IFD). Traditional direct microscopy, culture and histological techniques constitute the 'gold standard' against which newer tests are judged. Molecular diagnostic methods, whether broad-range or fungal-specific, have great potential to enhance sensitivity and speed of IFD diagnosis, but have varying specificities. The use of PCR-based assays, DNA sequencing, and other molecular methods including those incorporating proteomic approaches such as matrix-assisted laser desorption ionisation-time of flight mass spectroscopy (MALDI-TOF MS) have shown promising results. These are used mainly to complement conventional methods since they require standardisation before widespread implementation can be recommended. None are incorporated into diagnostic criteria for defining IFD. Commercial assays may assist standardisation. This review provides an update of molecular-based diagnostic approaches applicable to biological specimens and fungal cultures in microbiology laboratories. We focus on the most common pathogens, Candida and Aspergillus, and the mucormycetes. The position of molecular-based approaches in the detection of azole and echinocandin antifungal resistance is also discussed.
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50
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Quantitative Analysis of Single-Nucleotide Polymorphism for Rapid Detection of TR34/L98H- and TR46/Y121F/T289A-Positive Aspergillus fumigatus Isolates Obtained from Patients in Iran from 2010 to 2014. Antimicrob Agents Chemother 2015; 60:387-92. [PMID: 26525787 DOI: 10.1128/aac.02326-15] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 10/22/2015] [Indexed: 11/20/2022] Open
Abstract
We employed an endpoint genotyping method to update the prevalence rate of positivity for the TR34/L98H mutation (a 34-bp tandem repeat mutation in the promoter region of the cyp51A gene in combination with a substitution at codon L98) and the TR46/Y121F/T289A mutation (a 46-bp tandem repeat mutation in the promoter region of the cyp51A gene in combination with substitutions at codons Y121 and T289) among clinical Aspergillus fumigatus isolates obtained from different regions of Iran over a recent 5-year period (2010 to 2014). The antifungal activities of itraconazole, voriconazole, and posaconazole against 172 clinical A. fumigatus isolates were investigated using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) broth microdilution method. For the isolates with an azole resistance phenotype, the cyp51A gene and its promoter were amplified and sequenced. In addition, using a LightCycler 480 real-time PCR system, a novel endpoint genotyping analysis method targeting single-nucleotide polymorphisms was evaluated to detect the L98H and Y121F mutations in the cyp51A gene of all isolates. Of the 172 A. fumigatus isolates tested, the MIC values of itraconazole (≥16 mg/liter) and voriconazole (>4 mg/liter) were high for 6 (3.5%). Quantitative analysis of single-nucleotide polymorphisms showed the TR34/L98H mutation in the cyp51A genes of six isolates. No isolates harboring the TR46/Y121F/T289A mutation were detected. DNA sequencing of the cyp51A gene confirmed the results of the novel endpoint genotyping method. By microsatellite typing, all of the azole-resistant isolates had genotypes different from those previously recovered from Iran and from the Dutch TR34/L98H controls. In conclusion, there was not a significant increase in the prevalence of azole-resistant A. fumigatus isolates harboring the TR34/L98H resistance mechanism among isolates recovered over a recent 5-year period (2010 to 2014) in Iran. A quantitative assay detecting a single-nucleotide polymorphism in the cyp51A gene of A. fumigatus is a reliable tool for the rapid screening and monitoring of TR34/L98H- and TR46/Y121F/T289A-positive isolates and can easily be incorporated into clinical mycology algorithms.
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