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Hajigholamreza H, Sharifzadeh A, Hassan J, Shokri H, Akbaripazouki A, Pakbin B, Tamai IA. Influence of menthol on biofilm formation, ergosterol content, and cell surface hydrophobicity of Candida glabrata. FEMS Microbiol Lett 2023; 370:fnad065. [PMID: 37429611 DOI: 10.1093/femsle/fnad065] [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: 01/18/2023] [Revised: 06/21/2023] [Accepted: 07/03/2023] [Indexed: 07/12/2023] Open
Abstract
Resistance to synthetic antifungals has become one of the leading public health challenges around the world. Accordingly, novel antifungal products like naturally occurring molecules can be one of the potential ways to reach efficient curative approaches to control candidiasis. This work evaluated the effect of menthol on cell surface hydrophobicity (CSH), biofilm formation, growth, and ergosterol content of Candida glabrata, a yeast with a high resistance against antifungal agents. Disc diffusion method (susceptibility to synthetic antifungals), broth micro-dilution method (Susceptibility to menthol), 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide reduction assay (biofilm formation), High-performance liquid chromatography (HPLC) technique (ergosterol content), and adherence to n-hexadecane (CSH) were employed to determine the influence of menthol against C. glabrata isolates. The minimum inhibitory concentration (MIC) range of menthol versus C. glabrata was 1250-5000 µg/mL (mean ± SD: 3375 ± 1375 µg/mL). The mean rate of C. glabrata biofilm formation was decreased up to 97.67%, 81.15%, 71.21%, 63.72%, 47.53%, 26.31%, and 0.051% at 625, 1250, 2500, 5000, 10 000, 20 000, and 40 000 µg/mL concentrations, respectively. The percentages of CSH were significant in groups treated with MIC/2 (17.51 ± 5.52%) and MIC/4 (26 ± 5.87%) concentrations of menthol. Also, the percentage changes in membrane ergosterol were 15.97%, 45.34%, and 73.40% at 0.125, 0.25, and 0.5 mg/mL concentrations of menthol, respectively, in comparison with untreated control. The results showed the menthol impact versus sessile and planktonic C. glabrata cells, and the interference with ergosterol content, CSH, and biofilm formation, which made it a potent natural antifungal.
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Affiliation(s)
- Hamid Hajigholamreza
- Department of Microbiology and immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran 1416634793, Iran
| | - Aghil Sharifzadeh
- Department of Microbiology and immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran 1416634793, Iran
| | - Jalal Hassan
- Division of Toxicology, Department of Comparative Bioscience, Faculty of Veterinary Medicine, University of Tehran, Tehran 1416634793, Iran
| | - Hojjatollah Shokri
- Department of Pathobiology, Faculty of Veterinary Medicine, Amol University of Special Modern Technologies, Amol 4615664616, Iran
| | - Ali Akbaripazouki
- Department of Cell and Molecular Biology, School of Biology, College of Science, University of Tehran, Tehran 1416634793, Iran
| | - Babak Pakbin
- Werner Siemens Chair of Synthetic Biotechnology, Dept. of Chemistry, Technical University of Munich (TUM), Lichtenberg Str. 4, 85748 Garching bei München, Germany
- Institute for Life Technologies, University of Applied Sciences Western Switzerland Valais-Wallis, Sion 2 1950, Switzerland
| | - Iradj Ashrafi Tamai
- Department of Microbiology and immunology, Faculty of Veterinary Medicine, University of Tehran, Tehran 1416634793, Iran
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Anti-adherence and Anti-fungal Abilities of Thymol and Carvacrol Against Candida Species Isolated From Patients with Oral Candidiasis in Comparison with Fluconazole and Voriconazole. Jundishapur J Nat Pharm Prod 2021. [DOI: 10.5812/jjnpp.65005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Background: Natural isopropyl cresols, such as thymol and carvacrol, have been known to have antifungal activities. Objectives: The current study aimed to investigate the anti-adherence and antifungal activities of thymol, carvacrol, fluconazole, and voriconazole against oral isolates of Candida albicans (C. albicans), C. glabrata, and C. krusei. Methods: The susceptibility assay for the test compounds was performed using the disk diffusion method against all Candida isolates. Also, anti-adherence activity was examined using a rapid and highly reproducible 96 well microtiter-based method. Results: Both natural phenols and antifungal drugs revealed various efficacies against studied Candida species. The susceptibility to fluconazole and voriconazole were 100% for C. albicans, 50% and 90% for C. glabrata, and 0% and 100% for C. krusei isolates, respectively. The mean diameter of the inhibition zone was greater for thymol than carvacrol in C. albicans (19.89 ± 0.80 mm versus 17.05 ± 0.61 mm), C. glabrata (18.87 ± 0.71 mm versus 15.77 ± 0.57 mm), and C. krusei (15.11 ± 0.91 mm versus 13.91 ± 1.04 mm) isolates tested. Thymol showed more effective inhibition on adherence of all Candida species than other treatments. The mean relative adherence ratios for C. albicans, C. glabrata, and C. krusei were 0.50, 0.60, and 0.64, respectively. Conclusions: This study demonstrated significant inhibitory properties of thymol and carvacrol on the adherence and growth of azole susceptible- and -resistant Candida isolates. Also, thymol was more effective for preventing the adherence of yeast cells to polystyrene in comparison to carvacrol.
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Rasheed M, Battu A, Kaur R. Host-pathogen interaction in Candida glabrata infection: current knowledge and implications for antifungal therapy. Expert Rev Anti Infect Ther 2020; 18:1093-1103. [PMID: 32668993 DOI: 10.1080/14787210.2020.1792773] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
INTRODUCTION The opportunistic fungal pathogen Candida glabrata poses a clinical challenge in the successful treatment of invasive Candida infections, owing to its low inherent susceptibility toward azole antifungals and the recent acquisition of coresistance toward azole and echinocandin drugs. Compared to other prevalent Candida bloodstream pathogens, C. glabrata neither exhibits secreted proteolytic activity nor invokes a strong immune response in a variety of host cells and is less virulent. It also does not form true hyphae, and the success of C. glabrata, therefore, as a prevalent human fungal pathogen, appears to be built upon a distinct set of virulence attributes. AREAS COVERED The focus of this review is to outline, in brief, the interaction of C. glabrata with the host, deduced from the knowledge gained from different in vitro, ex vivo, and in vivo model systems. In addition, we briefly discuss the current antifungals, antifungal resistance mechanisms, and the development of new antifungal therapies, along with the available information on the host response. EXPERT OPINION A detailed understanding of stresses, selection pressures and differential immune responses in the presence and absence of antifungals that C. glabrata encounters in varied niches of the host, is required to design effective antifungal therapy.
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Affiliation(s)
- Mubashshir Rasheed
- Laboratory of Fungal Pathogenesis, Centre for DNA Fingerprinting and Diagnostics , Hyderabad, India
| | - Anamika Battu
- Laboratory of Fungal Pathogenesis, Centre for DNA Fingerprinting and Diagnostics , Hyderabad, India.,Graduate Studies, Manipal Academy of Higher Education , Manipal, India
| | - Rupinder Kaur
- Laboratory of Fungal Pathogenesis, Centre for DNA Fingerprinting and Diagnostics , Hyderabad, India
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Akyıldız Ö, Beşli Y, Kocagöz AS. Yoğun bakım ünitesinde bakteriyemi tanısı ile takip edilen hastaların değerlendirilmesi. CUKUROVA MEDICAL JOURNAL 2019. [DOI: 10.17826/cumj.623795] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Candida glabrata peroxiredoxins, Tsa1 and Tsa2, and sulfiredoxin, Srx1, protect against oxidative damage and are necessary for virulence. Fungal Genet Biol 2019; 135:103287. [PMID: 31654781 DOI: 10.1016/j.fgb.2019.103287] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 10/18/2019] [Accepted: 10/19/2019] [Indexed: 11/22/2022]
Abstract
Candida glabrata is an opportunistic fungal pathogen that can cause life-threatening infections in immunocompromised patients. To ensure a successful infection, C. glabrata has evolved a variety of strategies to avoid killing within the host. One of these strategies is the resistance to oxidative stress. Here we show that the sulfiredoxin Srx1 and the peroxiredoxins, Tsa1 and Tsa2, are implicated in the oxidative stress response (OSR) and required for virulence. We analyzed null mutations in SRX1, TSA1 and TSA2 and showed that TSA2 and SRX1 are required to respond to oxidative stress. While TSA1 expression is constitutive, SRX1 and TSA2 are induced in the presence of H2O2 in a process dependent on H2O2 concentration and on both transcription factors Yap1 and Skn7. Msn2 and Msn4 are not necessary for the regulation of SRX1, TSA1 and TSA2. Interestingly, TSA1 and TSA2, which are localized in the cytoplasm, are induced in the presence of neutrophils and required for survival in these phagocytic cells.
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Essential Role for the Phosphatidylinositol 3,5-Bisphosphate Synthesis Complex in Caspofungin Tolerance and Virulence in Candida glabrata. Antimicrob Agents Chemother 2019; 63:AAC.00886-19. [PMID: 31138567 PMCID: PMC6658794 DOI: 10.1128/aac.00886-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Accepted: 05/21/2019] [Indexed: 11/25/2022] Open
Abstract
Increasing resistance of the human opportunistic fungal pathogen Candida glabrata toward the echinocandin antifungals, which target the cell wall, is a matter of grave clinical concern. Echinocandin resistance in C. glabrata has primarily been associated with mutations in the β-glucan synthase-encoding genes C. glabrataFKS1 (CgFKS1) and CgFKS2. This notwithstanding, the role of the phosphoinositide signaling in antifungal resistance is just beginning to be deciphered. Increasing resistance of the human opportunistic fungal pathogen Candida glabrata toward the echinocandin antifungals, which target the cell wall, is a matter of grave clinical concern. Echinocandin resistance in C. glabrata has primarily been associated with mutations in the β-glucan synthase-encoding genes C. glabrataFKS1 (CgFKS1) and CgFKS2. This notwithstanding, the role of the phosphoinositide signaling in antifungal resistance is just beginning to be deciphered. The phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2] is a low-abundance lipid molecule that is pivotal to the intracellular membrane traffic. Here, we demonstrate for the first time that the PI(3,5)P2 kinase CgFab1, along with its activity regulator CgVac7 and the scaffolding protein CgVac14, is required for maintenance of the cell wall chitin content, survival of the cell wall, and caspofungin stress. Further, deletion analyses implicated the PI(3,5)P2 phosphatase CgFig4 in the regulation of PI(3,5)P2 levels and azole and echinocandin tolerance through CgVac14. We also show the localization of the CgFab1 lipid kinase to the vacuole to be independent of the CgVac7, CgVac14, and CgFig4 proteins. Lastly, our data demonstrate an essential requirement for PI(3,5)P2 signaling components, CgFab1, CgVac7, and CgVac14, in the intracellular survival and virulence in C. glabrata. Altogether, our data have yielded key insights into the functions and metabolism of PI(3,5)P2 lipid in the pathogenic yeast C. glabrata. In addition, our data highlight that CgVac7, whose homologs are absent in higher eukaryotes, may represent a promising target for antifungal therapy.
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Ben-Ami R. Treatment of Invasive Candidiasis: A Narrative Review. J Fungi (Basel) 2018; 4:jof4030097. [PMID: 30115843 PMCID: PMC6162658 DOI: 10.3390/jof4030097] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 08/08/2018] [Accepted: 08/12/2018] [Indexed: 12/29/2022] Open
Abstract
Invasive candidiasis occurs frequently in hospitalized patients, and is associated with high mortality rates due to delays in recognition and initiation of appropriate antifungals. Management of invasive candidiasis must take into account multiple host, pathogen, and drug-related factors, including the site of infection, host immune status, severity of sepsis, resistance and tolerance to antifungal agents, biofilm formation, and pharmacokinetic/pharmacodynamic considerations. Recent treatment directives have been shaped by the widespread introduction of echinocandins, highly potent and safe antifungals, into clinical use, as well as important changes in drug susceptibility patterns and the emergence of known and novel drug-resistant Candida species. Advances in molecular diagnostics have the potential to guide early targeted treatment of high-risk patients.
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Affiliation(s)
- Ronen Ben-Ami
- Infectious Diseases Unit, Tel Aviv Sourasky Medical Center, and the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv 64239, Israel.
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Byun SA, Won EJ, Kim MN, Lee WG, Lee K, Lee HS, Uh Y, Healey KR, Perlin DS, Choi MJ, Kim SH, Shin JH. Multilocus Sequence Typing (MLST) Genotypes of Candida glabrata Bloodstream Isolates in Korea: Association With Antifungal Resistance, Mutations in Mismatch Repair Gene (Msh2), and Clinical Outcomes. Front Microbiol 2018; 9:1523. [PMID: 30057573 PMCID: PMC6053515 DOI: 10.3389/fmicb.2018.01523] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 06/19/2018] [Indexed: 12/22/2022] Open
Abstract
Candida glabrata bloodstream infection (BSI) isolates from a particular geographic area have been reported to comprise a relatively small number of the major sequence types (STs) by multilocus sequence typing (MLST) analysis. Yet little is known about the characteristics of major ST strains of C. glabrata. To address this question in Korea, we investigated antifungal resistance and non-synonymous mutations of the mismatch repair gene (msh2 mutations) in C. glabrata BSI isolates, as well as associated clinical characteristics, and compared the results according to MLST genotype. We assessed a total of 209 C. glabrata BSI isolates from seven hospitals in Korea for 2 years (2009 and 2014). Clinical features of candidemia and their outcomes were analyzed for 185 available cases. According to MLST, ST7 (47.8%) was the most common type, followed by ST3 (22.5%); the remainder represented 28 types of minor STs (29.7%). Fluconazole-resistance (FR) rates for ST7, ST3, and other strains were 9.0% (9/100), 8.5% (4/47), and 4.8% (3/62), respectively, and all were susceptible to amphotericin B and micafungin. All ST7 isolates harbored the V239L mutation in msh2, known to confer hypermutability, while 91.5% of ST3 isolates did not harbor the msh2 mutation. Overall, isolates of the same ST had identical msh2 mutations, with the exception of nine isolates. The msh2 mutations were identified in 68.8% (11/16) of the FR isolates and 67.4% (130/193) of the fluconazole susceptible-dose dependent isolates. There was no significant difference in all clinical characteristics between ST3 and ST7. However, the 30-day mortality of C. glabrata candidemia due to the two major ST (ST3 or ST7) strains was significantly higher than that of candidemia due to other minor ST strains (45.1 vs. 25.0%, p < 0.05). Multivariate logistic regression analysis also showed that two major STs (ST3 and ST7) were independent predictors of 30-day mortality. This study showed for the first time that two STs (ST7 and ST3) were predominant among BSI isolates in Korea, and that C. glabrata BSI isolates belonging to two major MLST genotypes are characterized by higher mortality. In addition, most msh2 mutations align with MLST genotype, irrespective of FR.
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Affiliation(s)
- Seung A Byun
- Department of Laboratory Medicine, Chonnam National University Medical School, Gwangju, South Korea
| | - Eun Jeong Won
- Department of Laboratory Medicine, Chonnam National University Medical School, Gwangju, South Korea
| | - Mi-Na Kim
- Department of Laboratory Medicine, University of Ulsan College of Medicine and Asan Medical Center, Seoul, South Korea
| | - Wee Gyo Lee
- Department of Laboratory Medicine, Ajou University School of Medicine, Suwon, South Korea
| | - Kyungwon Lee
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, South Korea
| | - Hye Soo Lee
- Department of Laboratory Medicine, Chonbuk National University Hospital, Jeonju, South Korea
| | - Young Uh
- Department of Laboratory Medicine, Yonsei University Wonju College of Medicine, Wonju, South Korea
| | - Kelley R Healey
- Public Health Research Institute, New Jersey Medical School-Rutgers, The State University of New Jersey, Newark, NY, United States
| | - David S Perlin
- Public Health Research Institute, New Jersey Medical School-Rutgers, The State University of New Jersey, Newark, NY, United States
| | - Min Ji Choi
- Department of Laboratory Medicine, Chonnam National University Medical School, Gwangju, South Korea
| | - Soo Hyun Kim
- Department of Laboratory Medicine, Chonnam National University Medical School, Gwangju, South Korea
| | - Jong Hee Shin
- Department of Laboratory Medicine, Chonnam National University Medical School, Gwangju, South Korea
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Kounatidis I, Ames L, Mistry R, Ho HL, Haynes K, Ligoxygakis P. A Host-Pathogen Interaction Screen Identifies ada2 as a Mediator of Candida glabrata Defenses Against Reactive Oxygen Species. G3 (BETHESDA, MD.) 2018; 8:1637-1647. [PMID: 29535147 PMCID: PMC5940155 DOI: 10.1534/g3.118.200182] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 03/06/2018] [Indexed: 11/20/2022]
Abstract
Candida glabrata (C. glabrata) forms part of the normal human gut microbiota but can cause life-threatening invasive infections in immune-compromised individuals. C. glabrata displays high resistance to common azole antifungals, which necessitates new treatments. In this investigation, we identified five C. glabrata deletion mutants (∆ada2, ∆bas1, ∆hir3, ∆ino2 and ∆met31) from a library of 196 transcription factor mutants that were unable to grow and activate an immune response in Drosophila larvae. This highlighted the importance of these transcription factors in C. glabrata infectivity. Further ex vivo investigation into these mutants revealed the requirement of C. glabrata ADA2 for oxidative stress tolerance. We confirmed this observation in vivo whereby growth of the C. glabrata Δada2 strain was permitted only in flies with suppressed production of reactive oxygen species (ROS). Conversely, overexpression of ADA2 promoted C. glabrata replication in infected wild type larvae resulting in larval killing. We propose that ADA2 orchestrates the response of C. glabrata against ROS-mediated immune defenses during infection. With the need to find alternative antifungal treatment for C. glabrata infections, genes required for survival in the host environment, such as ADA2, provide promising potential targets.
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Affiliation(s)
- Ilias Kounatidis
- Cell Biology, Development and Genetics Laboratory, Department of Biochemistry, University of Oxford, OX1 3QU UK
| | - Lauren Ames
- Exeter Biosciences, College of Life and Environmental Sciences, University of Exeter, EX4 4QD, UK
| | - Rupal Mistry
- Cell Biology, Development and Genetics Laboratory, Department of Biochemistry, University of Oxford, OX1 3QU UK
| | - Hsueh-Lui Ho
- Exeter Biosciences, College of Life and Environmental Sciences, University of Exeter, EX4 4QD, UK
| | - Ken Haynes
- Exeter Biosciences, College of Life and Environmental Sciences, University of Exeter, EX4 4QD, UK
| | - Petros Ligoxygakis
- Cell Biology, Development and Genetics Laboratory, Department of Biochemistry, University of Oxford, OX1 3QU UK
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Population Structure of Candida parapsilosis: No Genetic Difference Between French and Uruguayan Isolates Using Microsatellite Length Polymorphism. Mycopathologia 2017; 183:381-390. [PMID: 29147867 DOI: 10.1007/s11046-017-0224-7] [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: 07/07/2017] [Accepted: 11/06/2017] [Indexed: 12/19/2022]
Abstract
Candida parapsilosis is a human commensal yeast, frequently involved in infection worldwide and especially in neonates. It is the second species responsible for bloodstream infections in Uruguay and the third species in France. We were interested in knowing whether the population structure of isolates responsible for candidemia in France and in Uruguay was different. Genotyping methods based on microsatellite length polymorphism (MLP) have been described and are especially used for investigation of local outbreaks. We therefore determined the genotypes of 159 C. parapsilosis isolates recovered from 122 patients (84 French patients from 43 hospitals and 38 Uruguayan patients from 10 hospitals) using three microsatellites markers previously described. Our results confirmed that C. parapsilosis population has a high genetic diversity, clonal inheritance and that majority of patients were infected by a single isolate. But we described recurrent infections due to related or unrelated genotypes resulting from isolates harboring loss or gain of heterozygosity. We also described three cases of coinfections due to unrelated genotypes. We did not uncover geographic specificity but observed two linked genotypes that seem to be associated with voriconazole resistance. Finally, among eight isolates involved in grouped cases, the genotypes were similar in six cases supporting the hypothesis of inter-patient transmission. These results confirmed the usefulness of performing MLP genotyping analysis for grouped cases of C. parapsilosis isolates in order to reinforce preventive hygiene measures.
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Ames L, Duxbury S, Pawlowska B, Ho HL, Haynes K, Bates S. Galleria mellonella as a host model to study Candida glabrata virulence and antifungal efficacy. Virulence 2017; 8:1909-1917. [PMID: 28658597 PMCID: PMC5750810 DOI: 10.1080/21505594.2017.1347744] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Affiliation(s)
- Lauren Ames
- a Biosciences, College of Life and Environmental Sciences, University of Exeter , Exeter , Devon , UK
| | - Sarah Duxbury
- a Biosciences, College of Life and Environmental Sciences, University of Exeter , Exeter , Devon , UK
| | - Bogna Pawlowska
- a Biosciences, College of Life and Environmental Sciences, University of Exeter , Exeter , Devon , UK
| | - Hsueh-Lui Ho
- a Biosciences, College of Life and Environmental Sciences, University of Exeter , Exeter , Devon , UK
| | - Ken Haynes
- a Biosciences, College of Life and Environmental Sciences, University of Exeter , Exeter , Devon , UK
| | - Steven Bates
- a Biosciences, College of Life and Environmental Sciences, University of Exeter , Exeter , Devon , UK
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Safety and Pharmacokinetics of CD101 IV, a Novel Echinocandin, in Healthy Adults. Antimicrob Agents Chemother 2017; 61:AAC.01627-16. [PMID: 27919901 PMCID: PMC5278714 DOI: 10.1128/aac.01627-16] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Accepted: 11/29/2016] [Indexed: 01/05/2023] Open
Abstract
CD101 IV is a novel echinocandin with distinctive pharmacokinetic properties that is being developed as a once-weekly treatment for candidemia and invasive candidiasis. CD101 has potent in vitro activity and in vivo efficacy against a broad range of Candida and Aspergillus species. The primary objective of two randomized, double-blind, placebo-controlled, dose-escalation studies in healthy adults was to determine the safety and tolerability of CD101 IV. Sequential cohorts of 8 subjects (n = 6, active; n = 2, placebo) were administered single (50, 100, 200, 400 mg) or multiple once-weekly (100 mg given once weekly for two weeks [×2], 200 mg ×2, 400 mg ×3) doses of CD101 IV infused over 1 h. There were no deaths, serious adverse events (SAEs), severe adverse events (AEs), or withdrawals from the study due to an AE. The majority of AEs were mild, and all completely resolved. There was a higher incidence of total AEs and mild transient infusion reactions in the 400-mg ×3 dose group. There were no clinically meaningful trends in postbaseline laboratory abnormalities and no safety issues related to electrocardiograms, vital signs, or physical exams. CD101 showed dose-proportional plasma exposures, minor accumulation (30% to 55%), low apparent clearance (<0.28 liter/h), long half-life (t1/2) (>80 h), and minimal urine excretion. CD101 IV was safe and well tolerated at single and multiple doses of up to 400 mg given once weekly for 3 weeks and exhibited a long t1/2, minimal accumulation over several weeks, negligible renal excretion, and high plasma exposures enabling once-weekly dosing.
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Andes DR, Safdar N, Baddley JW, Alexander B, Brumble L, Freifeld A, Hadley S, Herwaldt L, Kauffman C, Lyon GM, Morrison V, Patterson T, Perl T, Walker R, Hess T, Chiller T, Pappas PG. The epidemiology and outcomes of invasive Candida infections among organ transplant recipients in the United States: results of the Transplant-Associated Infection Surveillance Network (TRANSNET). Transpl Infect Dis 2016; 18:921-931. [PMID: 27643395 DOI: 10.1111/tid.12613] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Revised: 05/20/2016] [Accepted: 07/07/2016] [Indexed: 12/15/2022]
Abstract
BACKGROUND Invasive candidiasis (IC) is a common cause of mortality in solid organ transplant recipients (OTRs), but knowledge of epidemiology in this population is limited. METHOD The present analysis describes data from 15 US centers that prospectively identified IC from nearly 17 000 OTRs. Analyses were undertaken to determine predictors of infection and mortality. RESULTS A total of 639 cases of IC were identified. The most common species was Candida albicans (46.3%), followed by Candida glabrata (24.4%) and Candida parapsilosis (8.1%). In 68 cases >1 species was identified. The most common infection site was bloodstream (44%), followed by intra-abdominal (14%). The most frequently affected allograft groups were liver (41.1%) and kidney (35.3%). All-cause mortality at 90 days was 26.5% for all species and was highest for Candida tropicalis (44%) and C. parapsilosis (35.2%). Non-white race and female gender were more commonly associated with non-albicans species. A high rate of breakthrough IC was seen in patients receiving antifungal prophylaxis (39%). Factors associated with mortality include organ dysfunction, lung transplant, and treatment with a polyene antifungal. The only modifiable factor identified was choice of antifungal drug class based upon infecting Candida species. CONCLUSION These data highlight the common and distinct features of IC in OTRs.
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Affiliation(s)
- David R Andes
- Department of Medicine and Microbiology, University of Wisconsin, Madison, WI, USA
| | - Nasia Safdar
- Department of Medicine and Microbiology, University of Wisconsin, Madison, WI, USA
| | - John W Baddley
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Barbara Alexander
- Department of Medicine, Duke University School of Medicine, Durham, NC, USA
| | - Lisa Brumble
- Department of Medicine, Mayo Clinic, Rochester, MN, USA
| | - Allison Freifeld
- Department of Medicine, University of Nebraska, Lincoln, NE, USA
| | - Susan Hadley
- Department of Medicine, Tufts University, Boston, MA, USA
| | - Loreen Herwaldt
- Department of Medicine, University of Iowa School of Medicine, Iowa City, IA, USA
| | - Carol Kauffman
- Department of Medicine, Michigan University School of Medicine, Ann Arbor, MI, USA
| | | | - Vicki Morrison
- Department of Medicine, University of Minnesota School of Medicine, Minneapolis, MN, USA
| | - Thomas Patterson
- Department of Medicine, University of Texas at San Antonio, San Antonio, TX, USA
| | - Trish Perl
- Department of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | | | - Tim Hess
- Department of Medicine and Microbiology, University of Wisconsin, Madison, WI, USA
| | - Tom Chiller
- Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Peter G Pappas
- Department of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
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Opportunistic fungal pathogen Candida glabrata circulates between humans and yellow-legged gulls. Sci Rep 2016; 6:36157. [PMID: 27782182 PMCID: PMC5080578 DOI: 10.1038/srep36157] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 10/03/2016] [Indexed: 12/19/2022] Open
Abstract
The opportunistic pathogenic yeast Candida glabrata is a component of the mycobiota of both humans and yellow-legged gulls that is prone to develop fluconazole resistance. Whether gulls are a reservoir of the yeast and facilitate the dissemination of human C. glabrata strains remains an open question. In this study, MLVA genotyping highlighted the lack of genetic structure of 190 C. glabrata strains isolated from either patients in three hospitals or fecal samples collected from gull breeding colonies located in five distinct areas along the French Mediterranean littoral. Fluconazole-resistant isolates were evenly distributed between both gull and human populations. These findings demonstrate that gulls are a reservoir of this species and facilitate the diffusion of C. glabrata and indirect transmission to human or animal hosts via environmental contamination. This eco-epidemiological view, which can be applied to other vertebrate host species, broadens our perspective regarding the reservoirs and dissemination patterns of antifungal-resistant human pathogenic yeast.
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Heteroresistance to Fluconazole Is a Continuously Distributed Phenotype among Candida glabrata Clinical Strains Associated with In Vivo Persistence. mBio 2016; 7:mBio.00655-16. [PMID: 27486188 PMCID: PMC4981708 DOI: 10.1128/mbio.00655-16] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Candida glabrata causes persistent infections in patients treated with fluconazole and often acquires resistance following exposure to the drug. Here we found that clinical strains of C. glabrata exhibit cell-to-cell variation in drug response (heteroresistance). We used population analysis profiling (PAP) to assess fluconazole heteroresistance (FLCHR) and to ask if it is a binary trait or a continuous phenotype. Thirty (57.6%) of 52 fluconazole-sensitive clinical C. glabrata isolates met accepted dichotomous criteria for FLCHR. However, quantitative grading of FLCHR by using the area under the PAP curve (AUC) revealed a continuous distribution across a wide range of values, suggesting that all isolates exhibit some degree of heteroresistance. The AUC correlated with rhodamine 6G efflux and was associated with upregulation of the CDR1 and PDH1 genes, encoding ATP-binding cassette (ABC) transmembrane transporters, implying that HetR populations exhibit higher levels of drug efflux. Highly FLCHRC. glabrata was recovered more frequently than nonheteroresistant C. glabrata from hematogenously infected immunocompetent mice following treatment with high-dose fluconazole (45.8% versus 15%, P = 0.029). Phylogenetic analysis revealed some phenotypic clustering but also variations in FLCHR within clonal groups, suggesting both genetic and epigenetic determinants of heteroresistance. Collectively, these results establish heteroresistance to fluconazole as a graded phenotype associated with ABC transporter upregulation and fluconazole efflux. Heteroresistance may explain the propensity of C. glabrata for persistent infection and the emergence of breakthrough resistance to fluconazole. Heteroresistance refers to variability in the response to a drug within a clonal cell population. This phenomenon may have crucial importance for the way we look at antimicrobial resistance, as heteroresistant strains are not detected by standard laboratory susceptibility testing and may be associated with failure of antimicrobial therapy. We describe for the first time heteroresistance to fluconazole in C. glabrata, a finding that may explain the propensity of this pathogen to acquire resistance following exposure to fluconazole and to persist despite treatment. We found that, rather than being a binary all-or-none trait, heteroresistance was a continuously distributed phenotype associated with increased expression of genes that encode energy-dependent drug efflux transporters. Moreover, we show that heteroresistance is associated with failure of fluconazole to clear infection with C. glabrata. Together, these findings provide an empirical framework for determining and quantifying heteroresistance in C. glabrata.
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Andersen KM, Kristoffersen AK, Ingebretsen A, Vikholt KJ, Örtengren UT, Olsen I, Enersen M, Gaustad P. Diversity and antifungal susceptibility of Norwegian Candida glabrata clinical isolates. J Oral Microbiol 2016; 8:29849. [PMID: 26861194 PMCID: PMC4748091 DOI: 10.3402/jom.v8.29849] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2015] [Revised: 01/02/2016] [Accepted: 01/07/2016] [Indexed: 01/08/2023] Open
Abstract
Background Increasing numbers of immunocompromised patients have resulted in greater incidence of invasive fungal infections with high mortality. Candida albicans infections dominate, but during the last decade, Candida glabrata has become the second highest cause of candidemia in the United States and Northern Europe. Reliable and early diagnosis, together with appropriate choice of antifungal treatment, is needed to combat these challenging infections. Objectives To confirm the identity of 183 Candida glabrata isolates from different human body sites using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and VITEK®2, and to analyze isolate protein profiles and antifungal susceptibility. The minimum inhibitory concentration (MIC) of seven antifungal drugs was determined for the isolates to elucidate susceptibility. Design A total of 183 C. glabrata isolates obtained between 2002 and 2012 from Norwegian health-care units were analyzed. For species verification and differentiation, biochemical characterization (VITEK®2) and mass spectrometry (MALDI–TOF) were used. MIC determination for seven antifungal drugs was undertaken using E-tests®. Results Using VITEK®2, 92.9% of isolates were identified as C. glabrata, while all isolates (100%) were identified as C. glabrata using MALDI-TOF. Variation in protein spectra occurred for all identified C. glabrata isolates. The majority of isolates had low MICs to amphotericin B (≤1 mg/L for 99.5%) and anidulafungin (≤0.06 mg/L for 98.9%). For fluconazole, 18% of isolates had MICs >32 mg/L and 82% had MICs in the range ≥0.016 mg/L to ≤32 mg/L. Conclusions Protein profiles and antifungal susceptibility characteristics of the C. glabrata isolates were diverse. Clustering of protein profiles indicated that many azole resistant isolates were closely related. In most cases, isolates had highest susceptibility to amphotericin B and anidulafungin. The results confirmed previous observations of high MICs to fluconazole and flucytosine. MALDI-TOF was more definitive than VITEK®2 for C. glabrata identification.
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Affiliation(s)
- Kari-Mette Andersen
- Institute of Clinical Odontology, University of Tromsø, Tromsø, Norway.,Department of Oral Biology (DOB), Faculty of Dentistry, University of Oslo, Oslo, Norway;
| | | | - André Ingebretsen
- Department of Microbiology, Oslo University Hospital (OUS), Rikshospitalet, University of Oslo, Oslo, Norway
| | | | | | - Ingar Olsen
- Department of Oral Biology (DOB), Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Morten Enersen
- Department of Oral Biology (DOB), Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Peter Gaustad
- Department of Microbiology, Oslo University Hospital (OUS), Rikshospitalet, University of Oslo, Oslo, Norway
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Dostál J, Pecina A, Hrušková-Heidingsfeldová O, Marečková L, Pichová I, Řezáčová P, Lepšík M, Brynda J. Atomic resolution crystal structure of Sapp2p, a secreted aspartic protease from Candida parapsilosis. ACTA ACUST UNITED AC 2015; 71:2494-504. [PMID: 26627656 DOI: 10.1107/s1399004715019392] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 10/13/2015] [Indexed: 11/10/2022]
Abstract
The virulence of the Candida pathogens is enhanced by the production of secreted aspartic proteases, which therefore represent possible targets for drug design. Here, the crystal structure of the secreted aspartic protease Sapp2p from Candida parapsilosis was determined. Sapp2p was isolated from its natural source and crystallized in complex with pepstatin A, a classical aspartic protease inhibitor. The atomic resolution of 0.83 Å allowed the protonation states of the active-site residues to be inferred. A detailed comparison of the structure of Sapp2p with the structure of Sapp1p, the most abundant C. parapsilosis secreted aspartic protease, was performed. The analysis, which included advanced quantum-chemical interaction-energy calculations, uncovered molecular details that allowed the experimentally observed equipotent inhibition of both isoenzymes by pepstatin A to be rationalized.
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Affiliation(s)
- Jiří Dostál
- Institute of Organic Chemistry and Biochemistry (IOCB), Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 166 10 Prague 6, Czech Republic
| | - Adam Pecina
- Institute of Organic Chemistry and Biochemistry (IOCB), Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 166 10 Prague 6, Czech Republic
| | - Olga Hrušková-Heidingsfeldová
- Institute of Organic Chemistry and Biochemistry (IOCB), Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 166 10 Prague 6, Czech Republic
| | - Lucie Marečková
- Institute of Organic Chemistry and Biochemistry (IOCB), Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 166 10 Prague 6, Czech Republic
| | - Iva Pichová
- Institute of Organic Chemistry and Biochemistry (IOCB), Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 166 10 Prague 6, Czech Republic
| | - Pavlina Řezáčová
- Institute of Organic Chemistry and Biochemistry (IOCB), Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 166 10 Prague 6, Czech Republic
| | - Martin Lepšík
- Institute of Organic Chemistry and Biochemistry (IOCB), Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 166 10 Prague 6, Czech Republic
| | - Jiří Brynda
- Institute of Organic Chemistry and Biochemistry (IOCB), Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 166 10 Prague 6, Czech Republic
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Ho HL, Haynes K. Candida glabrata: new tools and technologies-expanding the toolkit. FEMS Yeast Res 2015; 15:fov066. [PMID: 26205243 PMCID: PMC4629792 DOI: 10.1093/femsyr/fov066] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 04/29/2015] [Accepted: 07/15/2015] [Indexed: 12/11/2022] Open
Abstract
In recent years, there has been a noticeable rise in fungal infections related to non-albicans Candida species, including Candida glabrata which has both intrinsic resistance to and commonly acquired resistance to azole antifungals. Phylogenetically, C. glabrata is more closely related to the mostly non-pathogenic model organism Saccharomyces cerevisiae than to other Candida species. Despite C. glabrata's designation as a pathogen by Wickham in 1957, relatively little is known about its mechanism of virulence. Over the past few years, technology to analyse the molecular basis of infection has developed rapidly, and here we briefly review the major advances in tools and technologies available to explore and investigate the virulence of C. glabrata that have occurred over the past decade.
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Affiliation(s)
- Hsueh-lui Ho
- Biosciences, University of Exeter, Stocker Road, Exeter, Devon EX4 4QD, UK
| | - Ken Haynes
- Biosciences, University of Exeter, Stocker Road, Exeter, Devon EX4 4QD, UK
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19
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Pfaller MA, Rhomberg PR, Messer SA, Jones RN, Castanheira M. Isavuconazole, micafungin, and 8 comparator antifungal agents' susceptibility profiles for common and uncommon opportunistic fungi collected in 2013: temporal analysis of antifungal drug resistance using CLSI species-specific clinical breakpoints and proposed epidemiological cutoff values. Diagn Microbiol Infect Dis 2015; 82:303-13. [PMID: 25986029 DOI: 10.1016/j.diagmicrobio.2015.04.008] [Citation(s) in RCA: 96] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Revised: 04/21/2015] [Accepted: 04/24/2015] [Indexed: 10/23/2022]
Abstract
The in vitro activities of isavuconazole, micafungin, and 8 comparator antifungal agents were determined for 1613 clinical isolates of fungi (1320 isolates of Candida spp., 155 of Aspergillus spp., 103 of non-Candida yeasts, and 35 non-Aspergillus molds) collected during a global survey conducted in 2013. The vast majority of the isolates of the 21 different species of Candida, with the exception of Candida glabrata (MIC90, 2 μg/mL), Candida krusei (MIC90, 1 μg/mL), and Candida guilliermondii (MIC90, 8 μg/mL), were inhibited by ≤0.25 μg/mL of isavuconazole. C. glabrata and C. krusei were largely inhibited by ≤1 μg/mL of isavuconazole. Resistance to fluconazole was seen in 0.5% of Candida albicans isolates, 11.1% of C. glabrata isolates, 2.5% of Candida parapsilosis isolates, 4.5% of Candida tropicalis isolates, and 20.0% of C. guilliermondii isolates. Resistance to the echinocandins was restricted to C. glabrata (1.3-2.1%) and C. tropicalis (0.9-1.8%). All agents except for the echinocandins were active against 69 Cryptococcus neoformans isolates, and the triazoles, including isavuconazole, were active against the other yeasts. Both the mold active triazoles as well as the echinocandins were active against 155 Aspergillus spp. isolates belonging to 10 species/species complex. In general, there was low resistance levels to the available systemically active antifungal agents in a large, contemporary (2013), global collection of molecularly characterized yeasts and molds. Resistance to azoles and echinocandins was most prominent among isolates of C. glabrata, C. tropicalis, and C. guilliermondii.
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Affiliation(s)
- M A Pfaller
- University of Iowa College of Medicine, Iowa City, IA; JMI Laboratories, North Liberty, IA.
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20
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Zhang L, Zhou S, Pan A, Li J, Liu B. Surveillance of antifungal susceptibilities in clinical isolates of Candida species at 36 hospitals in China from 2009 to 2013. Int J Infect Dis 2014; 33:1-4. [PMID: 25541294 DOI: 10.1016/j.ijid.2014.12.033] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 11/20/2014] [Accepted: 12/17/2014] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The purpose of this study was to determine the species distribution and to monitor the antifungal susceptibility profiles of clinical Candida isolates collected in China from 2009 to 2013. METHODS The antifungal susceptibilities of 952 Candida isolates were tested. RESULTS Candida albicans was the most common species, accounting for 65.7% of the total isolates. The most frequently isolated non-albicans Candida species in this study was Candida glabrata (193, 20.3%). Nearly 7.6%, 3.2%, 1.8%, and 1.1% of the 952 isolates exhibited decreased susceptibility to fluconazole, voriconazole, itraconazole, and flucytosine, respectively. Moreover, seven C. albicans and one Candida krusei had an amphotericin B minimum inhibitory concentration (MIC) of 2 μg/ml. CONCLUSIONS The distribution of species and the prevalence of antifungal resistance in Candida isolates varied among different areas in China. Continuous monitoring of resistance patterns is necessary to control the spread of resistance in clinical isolates of Candida species.
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Affiliation(s)
- Lei Zhang
- Department of Critical Care Medicine, Affiliated Anhui Provincial Hospital of Anhui Medical University, Hefei, China
| | - Shusheng Zhou
- Department of Critical Care Medicine, Affiliated Anhui Provincial Hospital of Anhui Medical University, Hefei, China
| | - Aijun Pan
- Department of Critical Care Medicine, Affiliated Anhui Provincial Hospital of Anhui Medical University, Hefei, China
| | - Jiabin Li
- Department of Infectious Disease, the First Affiliated Hospital of Anhui Medical University, Hefei, China; Anhui Centre for Surveillance of Bacterial Resistance, Hefei, China.
| | - Bao Liu
- Department of Critical Care Medicine, Affiliated Anhui Provincial Hospital of Anhui Medical University, Hefei, China; Department of Laboratory, Affiliated Anhui Provincial Hospital of Anhui Medical University, Hefei, China.
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Inukai T, Nagi M, Morita A, Tanabe K, Aoyama T, Miyazaki Y, Bard M, Nakayama H. The mannoprotein TIR3 (CAGL0C03872g) is required for sterol uptake in Candida glabrata. Biochim Biophys Acta Mol Cell Biol Lipids 2014; 1851:141-51. [PMID: 25463012 DOI: 10.1016/j.bbalip.2014.11.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2014] [Revised: 10/30/2014] [Accepted: 11/04/2014] [Indexed: 11/19/2022]
Abstract
Sterol uptake in the pathogenic fungus, Candida glabrata, occurs via the sterol transporter, CgAus1p. Azole inhibition of sterol biosynthesis can under certain circumstances be reversed by adding exogenously sterol. Here we demonstrate that the CgTIR3 (CAGL0C03872g) gene product is also required for sterol uptake, since Cgtir3Δ strains fail to take up sterol both aerobically and under hypoxic conditions. Western analysis using an HA-tagged TIR3 strain showed that CgTir3p localizes to the cell wall, and its expression is induced by serum. Semi-quantitative reverse transcriptase-PCR also showed that two transcription regulatory genes, CgUPC2A and CgUPC2B, control CgTIR3 as well as CgAUS1 gene expression. Interestingly, complementation studies using Cgtir3Δ showed that ScDAN1, a mannoprotein required for sterol uptake in Saccharomyces cerevisiae, could not complement the C. glabrata TIR3 function. Furthermore, sterol analyses, in which both the CgAUS1 and CgTIR3 genes were constitutively expressed, resulted in aerobic sterol uptake although the amount of uptake was considerably less than that of cells cultured aerobically with serum. These results suggest that additional factors other than CgAUS1 and CgTIR3 are required for sterol uptake in C. glabrata.
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Affiliation(s)
- Tatsuya Inukai
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, Japan; Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Japan; Division of Pathology, Immunology and Microbiology, Graduate School of Medicine, The University of Tokyo, Japan
| | - Minoru Nagi
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Japan
| | - Akihiro Morita
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, Japan
| | - Koichi Tanabe
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Japan
| | - Toshihiro Aoyama
- Department of Electronic and Information Engineering, Suzuka National College of Technology, Japan
| | - Yoshitsugu Miyazaki
- Department of Chemotherapy and Mycoses, National Institute of Infectious Diseases, Japan
| | - Martin Bard
- Department of Biology, Indiana University-Purdue University Indianapolis, USA
| | - Hironobu Nakayama
- Faculty of Pharmaceutical Sciences, Suzuka University of Medical Science, Japan.
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Abstract
Echinocandins are the newest antifungal agents approved for use in treating Candida infections in the US. They act by interfering with 1,3-β-D-glucan synthase and therefore disrupt cell wall production and lead to Candida cell death. There is no intrinsic resistance to echinocandins among Candida species, and isolates from historic collections archived before the release of the echinocandins show no resistance. Resistance to the echinocandins remains low among most Candida species and ranges overall from 0-1%. Among isolates of Candida glabrata, the proportion of resistant isolates is higher and has been reported to be as high as 13.5% in at least one hospital. Antifungal resistance is due to specific amino acid mutations in the Fksp subunit(s) of the 1,3-β-D-glucan synthase protein which are localized to one of two hotspots. These mutations are being recognized in isolates from patients who have failed echinocandin therapy, and often lead to a poor outcome. While the future looks bright for the echinocandins against most Candida species, C. glabrata remains a species of concern and resistance rates of C. glabrata to the echinocandins should be monitored closely.
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Minea B, Nastasa V, Moraru RF, Kolecka A, Flonta MM, Marincu I, Man A, Toma F, Lupse M, Doroftei B, Marangoci N, Pinteala M, Boekhout T, Mares M. Species distribution and susceptibility profile to fluconazole, voriconazole and MXP-4509 of 551 clinical yeast isolates from a Romanian multi-centre study. Eur J Clin Microbiol Infect Dis 2014; 34:367-83. [PMID: 25224578 DOI: 10.1007/s10096-014-2240-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Accepted: 08/27/2014] [Indexed: 01/22/2023]
Abstract
This is the first multi-centre study regarding yeast infections in Romania. The aim was to determine the aetiological spectrum and susceptibility pattern to fluconazole, voriconazole and the novel compound MXP-4509. The 551 isolates were identified using routine laboratory methods, matrix-assisted laser desorption ionisation time-of-flight mass spectrometry (MALDI-TOF MS) and DNA sequence analysis. Susceptibility testing was performed using the European Committee for Antimicrobial Susceptibility Testing (EUCAST) method and breakpoints. The yeasts originated from superficial infections (SUP, 51.5 %), bloodstream infections (BSI, 31.6 %) and deep-seated infections (DEEP, 16.9 %), from patients of all ages. Nine genera and 30 species were identified. The 20 Candida species accounted for 94.6 % of all isolates. C. albicans was the overall leading pathogen (50.5 %). Lodderomyces elongisporus is reported for the first time as a fungaemia cause in Europe. C. glabrata and Saccharomyces cerevisiae, as well as the non-Candida spp. and non-albicans Candida spp. groups, showed decreased fluconazole susceptibility (<75 %). The overall fluconazole resistance was 10.2 %. C. krusei accounted for 27 of the 56 fluconazole-resistant isolates. The overall voriconazole resistance was 2.5 % and was due mainly to C. glabrata and C. tropicalis isolates. Fluconazole resistance rates for the three categories of infection were similar to the overall value; voriconazole resistance rates differed: 4 % for BSI, 3.2 % for DEEP and 1.4 % for SUP. The antifungal activity of MXP-4509 was superior to voriconazole against C. glabrata and many fluconazole-resistant isolates. There was a large percentage of non-albicans Candida isolates. A large part of the high fluconazole resistance was not acquired but intrinsic, resulting from the high percentage of C. krusei.
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Affiliation(s)
- B Minea
- Advanced Research Centre for Bionanoconjugates and Biopolymers, Institute of Macromolecular Chemistry "Petru Poni", 700487, Iasi, Romania
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Pfaller MA, Andes DR, Diekema DJ, Horn DL, Reboli AC, Rotstein C, Franks B, Azie NE. Epidemiology and outcomes of invasive candidiasis due to non-albicans species of Candida in 2,496 patients: data from the Prospective Antifungal Therapy (PATH) registry 2004-2008. PLoS One 2014; 9:e101510. [PMID: 24991967 PMCID: PMC4081561 DOI: 10.1371/journal.pone.0101510] [Citation(s) in RCA: 286] [Impact Index Per Article: 28.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Accepted: 06/06/2014] [Indexed: 12/26/2022] Open
Abstract
This analysis describes the epidemiology and outcomes of invasive candidiasis caused by non-albicans species of Candida in patients enrolled in the Prospective Antifungal Therapy Alliance (PATH Alliance) registry from 2004 to 2008. A total of 2,496 patients with non-albicans species of Candida isolates were identified. The identified species were C. glabrata (46.4%), C. parapsilosis (24.7%), C. tropicalis (13.9%), C. krusei (5.5%), C. lusitaniae (1.6%), C. dubliniensis (1.5%) and C. guilliermondii (0.4%); 111 infections involved two or more species of Candida (4.4%). Non-albicans species accounted for more than 50% of all cases of invasive candidiasis in 15 of the 24 sites (62.5%) that contributed more than one case to the survey. Among solid organ transplant recipients, patients with non-transplant surgery, and patients with solid tumors, the most prevalent non-albicans species was C. glabrata at 63.7%, 48.0%, and 53.8%, respectively. In 1,883 patients receiving antifungal therapy on day 3, fluconazole (30.5%) and echinocandins (47.5%) were the most frequently administered monotherapies. Among the 15 reported species, 90-day survival was highest for patients infected with either C. parapsilosis (70.7%) or C. lusitaniae (74.5%) and lowest for patients infected with an unknown species (46.7%) or two or more species (53.2%). In conclusion, this study expands the current knowledge of the epidemiology and outcomes of invasive candidiasis caused by non-albicans species of Candida in North America. The variability in species distribution in these centers underscores the importance of local epidemiology in guiding the selection of antifungal therapy.
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Affiliation(s)
- Michael A. Pfaller
- JMI Laboratories, North Liberty, Iowa, United States of America
- Department of Pathology, University of Iowa, Iowa City, Iowa, United States of America
- * E-mail:
| | - David R. Andes
- Department of Medicine, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Daniel J. Diekema
- Department of Pathology, University of Iowa, Iowa City, Iowa, United States of America
| | - David L. Horn
- David Horn LLC, Doylestown, Pennsylvania, United States of America
| | - Annette C. Reboli
- Department of Medicine, Cooper Medical School of Rowan University, Camden, New Jersey, United States of America
| | - Coleman Rotstein
- Division of Infectious Diseases, Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Billy Franks
- Astellas Scientific and Medical Affairs, Northbrook, Illinois, United States of America
| | - Nkechi E. Azie
- Astellas Scientific and Medical Affairs, Northbrook, Illinois, United States of America
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Schwarzmüller T, Ma B, Hiller E, Istel F, Tscherner M, Brunke S, Ames L, Firon A, Green B, Cabral V, Marcet-Houben M, Jacobsen ID, Quintin J, Seider K, Frohner I, Glaser W, Jungwirth H, Bachellier-Bassi S, Chauvel M, Zeidler U, Ferrandon D, Gabaldón T, Hube B, d'Enfert C, Rupp S, Cormack B, Haynes K, Kuchler K. Systematic phenotyping of a large-scale Candida glabrata deletion collection reveals novel antifungal tolerance genes. PLoS Pathog 2014; 10:e1004211. [PMID: 24945925 PMCID: PMC4063973 DOI: 10.1371/journal.ppat.1004211] [Citation(s) in RCA: 133] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 05/13/2014] [Indexed: 11/28/2022] Open
Abstract
The opportunistic fungal pathogen Candida glabrata is a frequent cause of candidiasis, causing infections ranging from superficial to life-threatening disseminated disease. The inherent tolerance of C. glabrata to azole drugs makes this pathogen a serious clinical threat. To identify novel genes implicated in antifungal drug tolerance, we have constructed a large-scale C. glabrata deletion library consisting of 619 unique, individually bar-coded mutant strains, each lacking one specific gene, all together representing almost 12% of the genome. Functional analysis of this library in a series of phenotypic and fitness assays identified numerous genes required for growth of C. glabrata under normal or specific stress conditions, as well as a number of novel genes involved in tolerance to clinically important antifungal drugs such as azoles and echinocandins. We identified 38 deletion strains displaying strongly increased susceptibility to caspofungin, 28 of which encoding proteins that have not previously been linked to echinocandin tolerance. Our results demonstrate the potential of the C. glabrata mutant collection as a valuable resource in functional genomics studies of this important fungal pathogen of humans, and to facilitate the identification of putative novel antifungal drug target and virulence genes. Clinical infections by the yeast-like pathogen Candida glabrata have been ever-increasing over the past years. Importantly, C. glabrata is one of the most prevalent causes of drug-refractory fungal infections in humans. We have generated a novel large-scale collection encompassing 619 bar-coded C. glabrata mutants, each lacking a single gene. Extensive profiling of phenotypes reveals a number of novel genes implicated in tolerance to antifungal drugs that interfere with proper cell wall function, as well as genes affecting fitness of C. glabrata both during normal growth and under environmental stress. This fungal deletion collection will be a valuable resource for the community to study mechanisms of virulence and antifungal drug tolerance in C. glabrata, which is particularly relevant in view of the increasing prevalence of infections caused by this important human fungal pathogen.
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Affiliation(s)
- Tobias Schwarzmüller
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Biao Ma
- Department of Microbiology, Imperial College London, London, United Kingdom
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Ekkehard Hiller
- Molekulare Biotechnologie MBT Fraunhofer Institut für Grenzflächen- und Bioverfahrenstechnik IGB Fraunhofer, Stuttgart, Germany
| | - Fabian Istel
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Michael Tscherner
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Sascha Brunke
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
- Center for Sepsis Control and Care, CSCC, Jena University Hospital, Jena, Germany
| | - Lauren Ames
- Department of Microbiology, Imperial College London, London, United Kingdom
- Biosciences, College of Life & Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Arnaud Firon
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC2019, Paris, France
| | - Brian Green
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Vitor Cabral
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC2019, Paris, France
- Université Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur, Paris, France
| | - Marina Marcet-Houben
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG), Barcelona, Spain
| | - Ilse D. Jacobsen
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
- Center for Sepsis Control and Care, CSCC, Jena University Hospital, Jena, Germany
| | - Jessica Quintin
- UPR 9022 du CNRS, Université de Strasbourg, Equipe Fondation Recherche Médicale, Institut de Biologie Moléculaire et Cellulaire, Strasbourg, France
| | - Katja Seider
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
| | - Ingrid Frohner
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Walter Glaser
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
| | - Helmut Jungwirth
- Institut für Molekulare Biowissenschaften, Universität Graz, Graz, Austria
| | - Sophie Bachellier-Bassi
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
| | - Murielle Chauvel
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
| | - Ute Zeidler
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
| | - Dominique Ferrandon
- UPR 9022 du CNRS, Université de Strasbourg, Equipe Fondation Recherche Médicale, Institut de Biologie Moléculaire et Cellulaire, Strasbourg, France
| | - Toni Gabaldón
- Bioinformatics and Genomics Programme, Centre for Genomic Regulation (CRG), Barcelona, Spain
- Universitat Pompeu Fabra (UPF), Barcelona, Spain
| | - Bernhard Hube
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
- Friedrich Schiller University, Jena, Germany
- Center for Sepsis Control and Care, CSCC, Jena University Hospital, Jena, Germany
| | - Christophe d'Enfert
- Institut Pasteur, Unité Biologie et Pathogénicité Fongiques, Département Génomes et Génétique, Paris, France
- INRA, USC2019, Paris, France
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Steffen Rupp
- Molekulare Biotechnologie MBT Fraunhofer Institut für Grenzflächen- und Bioverfahrenstechnik IGB Fraunhofer, Stuttgart, Germany
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Brendan Cormack
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Ken Haynes
- Department of Microbiology, Imperial College London, London, United Kingdom
- Biosciences, College of Life & Environmental Sciences, University of Exeter, Exeter, United Kingdom
- * E-mail: (CE); (SR); (BC); (KH); (KK)
| | - Karl Kuchler
- Medical University Vienna, Max F. Perutz Laboratories, Department of Medical Biochemistry, Vienna, Austria
- * E-mail: (CE); (SR); (BC); (KH); (KK)
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Pfaller MA, Jones RN, Castanheira M. Regional data analysis of Candida non-albicans strains collected in United States medical sites over a 6-year period, 2006-2011. Mycoses 2014; 57:602-11. [PMID: 24863164 DOI: 10.1111/myc.12206] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 04/09/2014] [Accepted: 04/27/2014] [Indexed: 12/22/2022]
Abstract
Limited data are available on temporal and geographic variation of occurrence and antifungal resistance of non-C. albicans Candida species (non-CA-CSP) from the USA. The objective of this study was to evaluate the occurrence and antifungal resistance of 1694 isolates of non-CA-CSP collected during the period 2006-2011. Isolates were recovered in 33 hospitals located in four regions: Northcentral, North-east, South-east and West and tested using CLSI reference broth microdilution methods. Non-CA-CSP represented 55.6% of all Candida. C. glabrata was most predominant (39-42% of non-CA-CSP). Infections due to C. glabrata, C. krusei and C. dubliniensis increased over the 6 years. Anidulafungin (3.6%) and caspofungin (5.7%) resistance were prominent among C. glabrata from the North-east and West regions respectively. Resistance to micafungin was detected in 2.0% and 2.9% of C. glabrata from the West and North-east regions respectively. Echinocandin resistance was low, except for C. dubliniensis. Azole resistance was most prominent among C. glabrata from the South-east (13.6% fluconazole R) and the West (18.0%). Cross-resistance among three tested azoles was observed in C. glabrata from all regions. Whereas differences in species distribution and antifungal R varied across geographic regions, there was little evidence of temporal increase in resistance to azoles or echinocandins in the monitored non-CA-CSP.
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Wan L, Wang C, Liu L, Tang X, Wang J, Guan Y, Jiang M, Duan X, Ke X, Jing H, Hu J, Wang L, Li Y, Geng L. Efficacy and Safety of Micafungin as Prophylaxis for Invasive Fungal Disease in Neutropenic Patients with Hematologic Malignancies. INT J PHARMACOL 2014. [DOI: 10.3923/ijp.2014.231.236] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Aoyama T, Nakayama H, Ueno K, Inukai T, Tanabe K, Nagi M, Bard M, Chibana H. Genome-wide survey of transcriptional initiation in the pathogenic fungus, Candida glabrata. Genes Cells 2014; 19:478-503. [PMID: 24725256 DOI: 10.1111/gtc.12147] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 02/25/2014] [Indexed: 12/23/2022]
Abstract
DNA sequencing of the 5'-flanking region of the transcriptome effectively identifies transcription initiation sites and also aids in identifying unknown genes. This study describes a comprehensive polling of transcription start sites and an analysis of full-length complementary DNAs derived from the genome of the pathogenic fungus Candida glabrata. A comparison of the sequence reads derived from a cDNA library prepared from cells grown under different culture conditions against the reference genomic sequence of the Candida Genome Database (CGD: http://www.candidagenome.org/) revealed the expression of 4316 genes and their acknowledged transcription start sites (TSSs). In addition this analysis also predicted 59 new genes including 22 that showed no homology to the genome of Saccharomyces cerevisiae, a genetically close relative of C. glabrata. Furthermore, comparison of the 5'-untranslated regions (5'-UTRs) and core promoters of C. glabrata to those of S. cerevisiae showed various global similarities and differences among orthologous genes. Thus, the C. glabrata transcriptome can complement the annotation of the genome database and should provide new insights into the organization, regulation, and function of genes of this important human pathogen.
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Affiliation(s)
- Toshihiro Aoyama
- Department of Electronic and Information Engineering, Suzuka National College of Technology, Shiroko, Suzuka, Mie 510-0294, Japan
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Quindós G. Epidemiology of candidaemia and invasive candidiasis. A changing face. Rev Iberoam Micol 2013; 31:42-8. [PMID: 24270071 DOI: 10.1016/j.riam.2013.10.001] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2013] [Revised: 09/09/2013] [Accepted: 10/01/2013] [Indexed: 12/11/2022] Open
Abstract
Invasive candidiasis is a leading cause of mortality. Candidaemia is the most common clinical presentation of invasive candidiasis but more that 30% of these infections do not yield positive blood cultures. Candida albicans remains the predominant aetiology, accounting for 50% of all cases. However, there has been an epidemiological shift in the last decades. Some species of Candida different to C. albicans have emerged as an important cause of severe candidaemia as they can exhibit resistance to fluconazole and other antifungal agents. Moreover, there is a different distribution of non C. albicans Candida species in relationship to patients' and hospital characteristics. Thus, Candida parapsilosis has been associated to candidaemia in neonates and young adults. This species usually has an exogenously origin and contaminates medical devices, causing central venous catheter-associated candidaemias. Candida glabrata, Candida tropicalis and Candida krusei are isolated in blood cultures from older patients (>65 years) with important risk factors, such as major abdominal surgery, solid tumours and haematologic malignancies, transplants, and/or prolonged treatment with corticoids. Moreover, important geographical differences in the distribution of the Candida species different to C. albicans causing invasive candidiasis have been reported: C. parapsilosis predominates in Australia, Latin America and Mediterranean countries of Africa, Asia and Europe. In contrast, C. glabrata has an important aetiological role in USA and Central and Northern Europe. Finally, an important and worrying issue is that mortality due to invasive candidiasis remains unacceptably high. This manuscript is part of the series of works presented at the "V International Workshop: Molecular genetic approaches to the study of human pathogenic fungi" (Oaxaca, Mexico, 2012).
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Affiliation(s)
- Guillermo Quindós
- Departamento de Inmunología, Microbiología y Parasitología, UFI11/25 (Microbios y Salud), Facultad de Medicina y Odontología, Universidad del País Vasco/Euskal Herriko Unibertsitatea, Bilbao, Spain.
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Li D, Zhang W, Zheng S, Ma Z, Zhang P, Liu Z. Surveillance study of candidemia in cancer patients in North China. Med Mycol 2013; 51:378-84. [DOI: 10.3109/13693786.2012.727481] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Jang MJ, Shin JH, Lee WG, Kim MN, Lee K, Lee HS, Lee MK, Chang CL, Jang HC, Song ES, Kim SH, Shin MG, Suh SP, Ryang DW. In vitro fluconazole and voriconazole susceptibilities of Candida bloodstream isolates in Korea: use of the CLSI and EUCAST epidemiological cutoff values. Ann Lab Med 2013; 33:167-73. [PMID: 23667842 PMCID: PMC3646190 DOI: 10.3343/alm.2013.33.3.167] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Revised: 10/24/2012] [Accepted: 01/24/2013] [Indexed: 11/19/2022] Open
Abstract
Background At present, the clinical breakpoints (CBPs) of both fluconazole and voriconazole are available only for 3 common Candida species in the Clinical and Laboratory Standards Institute (CLSI) and the European Committee on Antimicrobial Susceptibility Testing (EUCAST) methods. Epidemiological cutoff values (ECVs) were recently applied to both methods to detect the emergence of acquired resistance (i.e., non-wild-type isolates) among 5 common Candida species. Methods We performed a nationwide study to determine the fluconazole and voriconazole susceptibility of Candida bloodstream isolates (BSIs) using both the CLSI and EUCAST methods. A total of 423 BSIs of 5 Candida species were collected from 8 hospitals. The azole susceptibilities were assessed on the basis of the species-specific CBPs and ECVs. Results Of the 341 BSIs of 3 common Candida species (i.e., C. albicans, C. tropicalis, and C. parapsilosis), 0.3% and 0.9%, 0.0% and 1.5% of isolates were categorized as fluconazole and voriconazole resistant according to the CLSI and EUCAST CBPs, respectively. Of 423 total BSIs, 1.4% and 2.6% had fluconazole minimum inhibitory concentrations (MICs) exceeding the ECVs according to the CLSI and EUCAST, respectively; 1.0% and 2.1% had voriconazole MICs exceeding the ECVs according to the CLSI and EUCAST, respectively. Categorical agreement between the methods using ECVs was 98.3% for fluconazole and 98.3% for voriconazole. Conclusions The EUCAST and CLSI methods using ECVs provide highly concordant results. Moreover, non-wild-type isolates with possibly acquired azole resistance were rare among the BSIs of 5 common Candida species in Korea.
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Affiliation(s)
- Min Joong Jang
- Department of Laboratory Medicine, Chonnam National University Medical School and Chonnam National University Hospital, Gwangju, Korea
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Abstract
BACKGROUND The antifungal armamentarium includes a number of drug classes and agents within each class. Successful IFI management depends on optimal matching of drug choice with the individual patient and causative pathogen, and maximizing effectiveness of the selected drug through appropriate dosing and toxicity management. OBJECTIVE This review is intended to provide a brief overview of key factors involved in optimizing antifungal choice and administration for patients with invasive fungal infections (IFIs). FINDINGS Antifungals differ in spectrum of activity, and these differences are critical when selecting the antifungal most likely to provide success for a patient with an IFI. When the species has not yet been identified, an analysis of regional epidemiology and risk factors can provide clues as to the most likely pathogen. For severely immunocompromised patients, a fungicidal agent may be preferred over a fungistatic agent, although more research is needed in this area. Triazoles, particularly itraconazole and posaconazole, exhibit great interpatient pharmacokinetic variability related to absorption. Steps can be taken to maximize absorption when using these agents. Voriconazole concentration is affected by polymorphisms in the major metabolic enzyme, cytochrome P450 2C19. Triazoles, and to a lesser extent other antifungals, are also subject to drug-drug interactions, which needs to be considered when selecting a particular antifungal agent for use in a severely ill patient on polypharmacy. Therapeutic drug monitoring may be a useful adjunct for patients receiving itraconazole, voriconazole, or posaconazole. When the IFI involves a pharmacologically protected site, such as the central nervous system (CNS) or eye, 5-fluorocytosine, fluconazole, or voriconazole are generally preferred. Echinocandin penetration is typically inadequate for IFIs of the CNS or eye. Antifungal agents also differ in their toxicity profiles, and these issues also need to be considered and managed when making an antifungal choice. CONCLUSION Successful management of IFIs relies in part on the accurate selection of an antifungal agent for the infection. Drug characteristics can help in the selection of drug therapy. These characteristics include the drug's spectrum of activity, pharmacokinetics, pharmacodynamics, toxicity profile, and distribution to the infection site. Matching the drug profile to the patient and fungal species contribute to optimal management of infection.
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Affiliation(s)
- David Andes
- University of Wisconsin School of Medicine and Public Health, Madison, WI, USA.
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Farahyar S, Zaini F, Kordbacheh P, Rezaie S, Safara M, Raoofian R, Heidari M. Overexpression of aldo-keto-reductase in azole-resistant clinical isolates of Candida glabrata determined by cDNA-AFLP. ACTA ACUST UNITED AC 2013; 21:1. [PMID: 23351326 PMCID: PMC3556022 DOI: 10.1186/2008-2231-21-1] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2012] [Accepted: 12/29/2012] [Indexed: 01/05/2023]
Abstract
Background Candida glabrata causes significant medical problems in immunocompromised patients. Many strains of this yeast are intrinsically resistant to azole antifungal agents, and treatment is problematic, leading to high morbidity and mortality rates in immunosuppressed individuals. The primary goal of this study was to investigate the genes involved in the drug resistance of clinical isolates of C. glabrata. Methods The clinical isolates of C. glabrata were collected in an epidemiological survey of candidal infection in immunocompromised patients and consisted of four fluconazole and itraconazole resistant isolates, two fluconazole and itraconazole sensitive isolates, and C. glabrata CBS 138 as reference strain. Antifungal susceptibility patterns of the organisms were determined beforehand by the Clinical and Laboratory Standards Institute (CLSI). The potential gene(s) implicated in antifungal resistance were investigated using complementary DNA- Amplified Fragment Length Polymorphism (cDNA-AFLP). Semi-quantitative RT-PCR was carried out to evaluate the expression of gene(s) in resistant isolates as compared to sensitive and reference strains. Results and conclusions The aldo-keto-reductase superfamily (AKR gene) was upregulated in the resistant clinical isolates as assessed by cDNA-AFLP. Semi-quantitative RT-PCR revealed AKR mRNA expression approximately twice that seen in the sensitive isolates. Overexpression of the AKR gene was associated with increased fluconazole and itraconazole resistance in C. glabrata. The data suggest that upregulation of the AKR gene might give a new insight into the mechanism of azole resistance.
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Affiliation(s)
- Shirin Farahyar
- Department of Medical Mycology and Parasitology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
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Colombo AL, Garnica M, Aranha Camargo LF, Da Cunha CA, Bandeira AC, Borghi D, Campos T, Senna AL, Valias Didier ME, Dias VC, Nucci M. Candida glabrata: an emerging pathogen in Brazilian tertiary care hospitals. Med Mycol 2013; 51:38-44. [DOI: 10.3109/13693786.2012.698024] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Epidemiology and outcomes of candidemia in 3648 patients: data from the Prospective Antifungal Therapy (PATH Alliance®) registry, 2004–2008. Diagn Microbiol Infect Dis 2012; 74:323-31. [DOI: 10.1016/j.diagmicrobio.2012.10.003] [Citation(s) in RCA: 287] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 10/05/2012] [Indexed: 12/29/2022]
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Kuper KM, Coyle EA, Wanger A. Antifungal Susceptibility Testing: A Primer for Clinicians. Pharmacotherapy 2012; 32:1112-22. [DOI: 10.1002/phar.1146] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Kristi M. Kuper
- Department of Quality Services; Cardinal Health; Houston; Texas
| | | | - Audrey Wanger
- Department of Pathology; University of Texas Medical School; Houston; Texas
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Bergamasco MD, Garnica M, Colombo AL, Nucci M. Epidemiology of candidemia in patients with hematologic malignancies and solid tumours in Brazil. Mycoses 2012; 56:256-63. [DOI: 10.1111/myc.12013] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Cleveland AA, Farley MM, Harrison LH, Stein B, Hollick R, Lockhart SR, Magill SS, Derado G, Park BJ, Chiller TM. Changes in incidence and antifungal drug resistance in candidemia: results from population-based laboratory surveillance in Atlanta and Baltimore, 2008-2011. Clin Infect Dis 2012; 55:1352-61. [PMID: 22893576 DOI: 10.1093/cid/cis697] [Citation(s) in RCA: 265] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Candidemia is common and associated with high morbidity and mortality; changes in population-based incidence rates have not been reported. METHODS We conducted active, population-based surveillance in metropolitan Atlanta, Georgia, and Baltimore City/County, Maryland (combined population 5.2 million), during 2008-2011. We calculated candidemia incidence and antifungal drug resistance compared with prior surveillance (Atlanta, 1992-1993; Baltimore, 1998-2000). RESULTS We identified 2675 cases of candidemia with 2329 isolates during 3 years of surveillance. Mean annual crude incidence per 100 000 person-years was 13.3 in Atlanta and 26.2 in Baltimore. Rates were highest among adults aged ≥65 years (Atlanta, 59.1; Baltimore, 72.4) and infants (aged <1 year; Atlanta, 34.3; Baltimore, 46.2). In both locations compared with prior surveillance, adjusted incidence significantly declined for infants of both black and white race (Atlanta: black risk ratio [RR], 0.26 [95% confidence interval {CI}, .17-.38]; white RR: 0.19 [95% CI, .12-.29]; Baltimore: black RR, 0.38 [95% CI, .22-.64]; white RR: 0.51 [95% CI: .29-.90]). Prevalence of fluconazole resistance (7%) was unchanged compared with prior surveillance; 32 (1%) isolates were echinocandin-resistant, and 9 (8 Candida glabrata) were multidrug resistant to both fluconazole and an echinocandin. CONCLUSIONS We describe marked shifts in candidemia epidemiology over the past 2 decades. Adults aged ≥65 years replaced infants as the highest incidence group; adjusted incidence has declined significantly in infants. Use of antifungal prophylaxis, improvements in infection control, or changes in catheter insertion practices may be contributing to these declines. Further surveillance for antifungal resistance and efforts to determine effective prevention strategies are needed.
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Affiliation(s)
- Angela Ahlquist Cleveland
- Mycotic Diseases Branch, Division of Foodborne, Waterborne and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
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Ten-Year Study of Species Distribution and Antifungal Susceptibilities of Candida Bloodstream Isolates at a Brazilian Tertiary Hospital. Mycopathologia 2012; 174:389-96. [DOI: 10.1007/s11046-012-9566-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Accepted: 07/03/2012] [Indexed: 10/28/2022]
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Candida glabrata: Multidrug Resistance and Increased Virulence in a Major Opportunistic Fungal Pathogen. CURRENT FUNGAL INFECTION REPORTS 2012. [DOI: 10.1007/s12281-012-0091-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Schmalreck AF, Willinger B, Haase G, Blum G, Lass-Flörl C, Fegeler W, Becker K. Species and susceptibility distribution of 1062 clinical yeast isolates to azoles, echinocandins, flucytosine and amphotericin B from a multi-centre study. Mycoses 2012; 55:e124-37. [DOI: 10.1111/j.1439-0507.2011.02165.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Tavanti A, Maisetta G, Del Gaudio G, Petruzzelli R, Sanguinetti M, Batoni G, Senesi S. Fungicidal activity of the human peptide hepcidin 20 alone or in combination with other antifungals against Candida glabrata isolates. Peptides 2011; 32:2484-7. [PMID: 22015266 DOI: 10.1016/j.peptides.2011.10.012] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 10/06/2011] [Accepted: 10/06/2011] [Indexed: 11/28/2022]
Abstract
Candida glabrata infections are often difficult to eradicate due to the intrinsically low susceptibility to azoles of this species. In addition, C. glabrata has also been shown to be insensitive to several cationic peptides, which have been shown to be promising novel therapeutic candidates for the treatment of fungal infection. In this study, the in vitro fungicidal activity of the human cationic peptide hepcidin 20 (Hep-20) was evaluated against clinical isolates of C. glabrata with different levels of fluconazole susceptibility. Interestingly, all isolates were susceptible to Hep-20 (100-200 μg/ml) at pH 7.4, whereas the fungicidal effect of the peptide was higher (50 μg/ml) at acidic pH values. In addition, an increased antifungal activity was observed for Hep-20 with amphotericin B and a synergistic effect was demonstrated for the Hep-20/fluconazole and Hep-20/caspofungin combinations.
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Affiliation(s)
- Arianna Tavanti
- Dipartimento di Biologia, Università di Pisa, Via San Zeno, 37, 56127 Pisa, Italy.
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Rambach G, Oberhauser H, Speth C, Lass-Flörl C. Susceptibility of Candida species and various moulds to antimycotic drugs: use of epidemiological cutoff values according to EUCAST and CLSI in an 8-year survey. Med Mycol 2011; 49:856-63. [DOI: 10.3109/13693786.2011.583943] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Sinnollareddy M, Peake SL, Roberts MS, Playford EG, Lipman J, Roberts JA. Pharmacokinetic evaluation of fluconazole in critically ill patients. Expert Opin Drug Metab Toxicol 2011; 7:1431-40. [PMID: 21883033 DOI: 10.1517/17425255.2011.615309] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
INTRODUCTION Invasive candidiasis has emerged over the last few decades as an increasingly important nosocomial problem for the critically ill, affecting around 2% of intensive care unit patients. Although poor outcomes associated with invasive candidiasis among critically ill patients may relate to severe underlying disease processes and delayed institution of antifungal therapy, inadequate dosing of antifungal agents may also contribute. AREAS COVERED This drug evaluation provides a critical appraisal of the published literature pertaining to the pharmacokinetics of fluconazole in critically ill, obese or severely burned patients, including those receiving acute renal replacement therapy. The pharmacodynamics of fluconazole is also covered, as well as the likely clinical implications for optimal dosing and the toxicity of fluconazole. Last, variations in fluconazole susceptibility patterns of Candida spp. are also discussed. EXPERT OPINION Recently, there has been an increased but geographically variable prevalence of non-albicans Candida spp., causing invasive candidiasis and an overall trend towards reduced fluconazole susceptibility. The pathophysiological changes of critical illness, coupled with a lack of dose finding studies, support the use of local susceptibility patterns to guide fluconazole dosing until such time as pharmacokinetic-pharmacodynamic information to guide optimal fluconazole dosing strategies and pharmacodynamic targets becomes available.
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Lott TJ, Frade JP, Lyon GM, Iqbal N, Lockhart SR. Bloodstream and non-invasive isolates of Candida glabrata have similar population structures and fluconazole susceptibilities. Med Mycol 2011; 50:136-42. [PMID: 21838617 DOI: 10.3109/13693786.2011.592153] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We have compared multilocus sequence typing (MLST) and fluconazole susceptibility profiles of Candida glabrata bloodstream isolates obtained during active, population-based surveillance to those obtained from non-sterile sites of individuals with no evidence of fungal disease (i.e., non-invasive isolates) in the same US city during an overlapping time period. In each of the two populations, different proportions of the same six major sequence types (STs) encompassed 82% of the isolates. One ST was more prevalent in the candidemia population and two other STs were more prevalent in the non-invasive population, but the overall allelic frequencies within the groups suggested little, if any, genotypic diversity between them. Fluconazole susceptibility profiles of isolates from the patients in the two groups were not significantly different and were not associated with a particular sequence type. Our results support the hypothesis that C. glabrata strains causing bloodstream infections are genetically indistinguishable from those normally residing in/on the host, suggesting that relative pathogenicity may be closely tied to commensalism.
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Affiliation(s)
- Timothy J Lott
- Mycotic Diseases Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, Mailstop G-11, Atlanta, GA 30333, USA
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Discovery of a novel class of orally active antifungal beta-1,3-D-glucan synthase inhibitors. Antimicrob Agents Chemother 2011; 55:5099-106. [PMID: 21844320 DOI: 10.1128/aac.00432-11] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The echinocandins are a class of semisynthetic natural products that target β-1,3-glucan synthase (GS). Their proven clinical efficacy combined with minimal safety issues has made the echinocandins an important asset in the management of fungal infection in a variety of patient populations. However, the echinocandins are delivered only parenterally. A screen for antifungal bioactivities combined with mechanism-of-action studies identified a class of piperazinyl-pyridazinones that target GS. The compounds exhibited in vitro activity comparable, and in some cases superior, to that of the echinocandins. The compounds inhibit GS in vitro, and there was a strong correlation between enzyme inhibition and in vitro antifungal activity. In addition, like the echinocandins, the compounds caused a leakage of cytoplasmic contents from yeast and produced a morphological response in molds characteristic of GS inhibitors. Spontaneous mutants of Saccharomyces cerevisiae with reduced susceptibility to the piperazinyl-pyridazinones had substitutions in FKS1. The sites of these substitutions were distinct from those conferring resistance to echinocandins; likewise, echinocandin-resistant isolates remained susceptible to the test compounds. Finally, we present efficacy and pharmacokinetic data on an example of the piperazinyl-pyridazinone compounds that demonstrated efficacy in a murine model of Candida glabrata infection.
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Comparative in vitro activities of fluconazole, voriconazole, and MXP-4509 against Romanian blood yeast isolates. Mycopathologia 2011; 172:487-92. [PMID: 21805354 DOI: 10.1007/s11046-011-9455-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 07/19/2011] [Indexed: 10/17/2022]
Abstract
The aim of the study was to evaluate the antifungal activity of a new triazole formulation against 182 clinical isolates of yeasts recovered from blood cultures in three tertiary hospitals in Romania and to compare its activity with those of fluconazole and voriconazole. In vitro susceptibility was assessed by following the guidelines of AFST-EUCAST E. Def. 7.1. The distribution of minimum inhibitory concentrations (MICs) of MXP-4509 was very similar to that of voriconazole (MIC(50): 0.0312 mg/l vs. 0.0156 mg/l; MIC(90): 0.25 mg/l vs. 0.25 mg/l), but significantly different from that of fluconazole (MIC(50): 0.0312 mg/l vs. 0.5 mg/l; MIC(90): 0.25 mg/l vs. 32 mg/l). The new triazole MXP-4509 proved to have a good in vitro antifungal activity raising the interest for further pharmacological and microbiological investigations in order to assess its potential advantages for therapy.
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Tapia GG, Razonable RR, Eckel-Passow JE, Lahr BD, Afessa B, Keegan MT, Catania J, Baddour LM. A scoring model of factors associated with Candida glabrata candidemia among critically ill patients. Mycoses 2011; 55:228-36. [PMID: 21777296 DOI: 10.1111/j.1439-0507.2011.02069.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Candida species, including Candida glabrata (CG), are common causes of bloodstream infections among intensive care unit (ICU) patients. Many CG isolates have decreased susceptibility to fluconazole. Constructing a scoring model of factors associated with CG candidemia in ICU patients that can be used if fluconazole susceptibility testing is not readily available. We identified patients with candidemia that were admitted to the ICU of the Mayo Clinic in Rochester, Minnesota from 1998 to 2006. Using patient demographical and clinical data abstracted via chart review, a multivariable logistic regression model was developed to distinguish those with CG candidemia. We identified 246 patients with candidemia including 68 CG cases. Multivariable analysis identified four independent factors associated with CG candidemia: absence of renal failure, less than 7 days in the hospital, abdominal surgery and fluconazole use. The predictive ability of the model, based on the c-statistic, was 0.727. In a large ICU cohort, a scoring model that included four risk factors, which are readily ascertainable at the bedside, was created to distinguish candidemia due to CG from other causes of candidemia. The identification of risk factors associated with CG candidemia could aid physicians in the selection of the optimal initial antifungal therapy.
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Affiliation(s)
- Gino G Tapia
- Department of Infectious Diseases, Sanford Health, Fargo, ND 58122, USA.
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Ferrari S, Sanguinetti M, Torelli R, Posteraro B, Sanglard D. Contribution of CgPDR1-regulated genes in enhanced virulence of azole-resistant Candida glabrata. PLoS One 2011; 6:e17589. [PMID: 21408004 PMCID: PMC3052359 DOI: 10.1371/journal.pone.0017589] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Accepted: 01/27/2011] [Indexed: 12/20/2022] Open
Abstract
In Candida glabrata, the transcription factor CgPdr1 is involved
in resistance to azole antifungals via upregulation of ATP binding cassette
(ABC)-transporter genes including at least CgCDR1,
CgCDR2 and CgSNQ2. A high diversity of GOF
(gain-of-function) mutations in CgPDR1 exists for the
upregulation of ABC-transporters. These mutations enhance C.
glabrata virulence in animal models, thus indicating that
CgPDR1 might regulate the expression of yet unidentified
virulence factors. We hypothesized that CgPdr1-dependent virulence factor(s)
should be commonly regulated by all GOF mutations in CgPDR1. As
deduced from transcript profiling with microarrays, a high number of genes (up
to 385) were differentially regulated by a selected number (7) of GOF mutations
expressed in the same genetic background. Surprisingly, the transcriptional
profiles resulting from expression of GOF mutations showed minimal overlap in
co-regulated genes. Only two genes, CgCDR1 and
PUP1 (for PDR1upregulated and encoding a mitochondrial protein), were
commonly upregulated by all tested GOFs. While both genes mediated azole
resistance, although to different extents, their deletions in an azole-resistant
isolate led to a reduction of virulence and decreased tissue burden as compared
to clinical parents. As expected from their role in C. glabrata
virulence, the two genes were expressed as well in vitro and
in vivo. The individual overexpression of these two genes
in a CgPDR1-independent manner could partially restore
phenotypes obtained in clinical isolates. These data therefore demonstrate that
at least these two CgPDR1-dependent and -upregulated genes
contribute to the enhanced virulence of C. glabrata that
acquired azole resistance.
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Affiliation(s)
- Sélène Ferrari
- Institute of Microbiology, University of
Lausanne and University Hospital Center, Lausanne, Switzerland
| | | | - Riccardo Torelli
- Institute of Microbiology, Università
Cattolica del Sacro Cuore, Rome, Italy
| | - Brunella Posteraro
- Institute of Microbiology, Università
Cattolica del Sacro Cuore, Rome, Italy
| | - Dominique Sanglard
- Institute of Microbiology, University of
Lausanne and University Hospital Center, Lausanne, Switzerland
- * E-mail:
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