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Marschall E, Cass RW, Prasad KM, Swarbrick JD, McKay AI, Payne JAE, Cryle MJ, Tailhades J. Synthetic ramoplanin analogues are accessible by effective incorporation of arylglycines in solid-phase peptide synthesis. Chem Sci 2023; 15:195-203. [PMID: 38131086 PMCID: PMC10732013 DOI: 10.1039/d3sc01944f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Accepted: 09/09/2023] [Indexed: 12/23/2023] Open
Abstract
The threat of antimicrobial resistance to antibiotics requires a continual effort to develop alternative treatments. Arylglycines (or phenylglycines) are one of the signature amino acids found in many natural peptide antibiotics, but their propensity for epimerization in solid-phase peptide synthesis (SPPS) has prevented their use in long peptide sequences. We have now identified an optimized protocol that allows the synthesis of challenging non-ribosomal peptides including precursors of the glycopeptide antibiotics and an analogue of feglymycin (1 analogue, 20%). We have exploited this protocol to synthesize analogues of the peptide antibiotic ramoplanin using native chemical ligation/desulfurization (1 analogue, 6.5%) and head-to-tail macrocyclization in excellent yield (6 analogues, 3-9%), with these compounds extensively characterized by NMR (U-shaped structure) and antimicrobial activity assays (two clinical isolates). This method significantly reduces synthesis time (6-9 days) when compared with total syntheses (2-3 months) and enables drug discovery programs to include arylglycines in structure-activity relationship studies and drug development.
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Affiliation(s)
- Edward Marschall
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Rachel W Cass
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Komal M Prasad
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - James D Swarbrick
- Department of Microbiology, Monash University Clayton VIC 3800 Australia
| | - Alasdair I McKay
- Department of Chemistry, Monash University Clayton VIC 3800 Australia
| | - Jennifer A E Payne
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Max J Cryle
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
| | - Julien Tailhades
- Department of Biochemistry and Molecular Biology, The Monash Biomedicine Discovery Institute, Monash University Clayton VIC 3800 Australia
- EMBL Australia, Monash University Clayton VIC 3800 Australia
- ARC Centre of Excellence for Innovations in Peptide and Protein Science Clayton VIC 3800 Australia
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2
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Mehrabi MR, Soltani M, Chiani M, Raahemifar K, Farhangi A. Nanomedicine: New Frontiers in Fighting Microbial Infections. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:483. [PMID: 36770443 PMCID: PMC9920255 DOI: 10.3390/nano13030483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 01/21/2023] [Accepted: 01/22/2023] [Indexed: 06/18/2023]
Abstract
Microbes have dominated life on Earth for the past two billion years, despite facing a variety of obstacles. In the 20th century, antibiotics and immunizations brought about these changes. Since then, microorganisms have acquired resistance, and various infectious diseases have been able to avoid being treated with traditionally developed vaccines. Antibiotic resistance and pathogenicity have surpassed antibiotic discovery in terms of importance over the course of the past few decades. These shifts have resulted in tremendous economic and health repercussions across the board for all socioeconomic levels; thus, we require ground-breaking innovations to effectively manage microbial infections and to provide long-term solutions. The pharmaceutical and biotechnology sectors have been radically altered as a result of nanomedicine, and this trend is now spreading to the antibacterial research community. Here, we examine the role that nanomedicine plays in the prevention of microbial infections, including topics such as diagnosis, antimicrobial therapy, pharmaceutical administration, and immunizations, as well as the opportunities and challenges that lie ahead.
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Affiliation(s)
- Mohammad Reza Mehrabi
- Department of NanoBiotechnology, Pasteur Institute of Iran, Tehran 13169-43551, Iran
| | - Madjid Soltani
- Department of Mechanical Engineering, K. N. Toosi University of Technology, Tehran 19967-15433, Iran
- Advanced Bioengineering Initiative Center, Multidisciplinary International Complex, K. N. Toosi University of Technology, Tehran 14176-14411, Iran
- Centre for Biotechnology and Bioengineering (CBB), University of Waterloo, Waterloo, ON N2L 3G1, Canada
- Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - Mohsen Chiani
- Department of NanoBiotechnology, Pasteur Institute of Iran, Tehran 13169-43551, Iran
| | - Kaamran Raahemifar
- Data Science and Artificial Intelligence Program, College of Information Sciences and Technology (IST), Penn State University, State College, PA 16801, USA
- Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada
- School of Optometry and Vision Science, Faculty of Science, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada
| | - Ali Farhangi
- Department of NanoBiotechnology, Pasteur Institute of Iran, Tehran 13169-43551, Iran
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Pitcher NP, Harjani JR, Zhao Y, Jin J, Knight DR, Li L, Putsathit P, Riley TV, Carter GP, Baell JB. Development of 1,2,4-Oxadiazole Antimicrobial Agents to Treat Enteric Pathogens within the Gastrointestinal Tract. ACS OMEGA 2022; 7:6737-6759. [PMID: 35252669 PMCID: PMC8892681 DOI: 10.1021/acsomega.1c06294] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 02/03/2022] [Indexed: 06/14/2023]
Abstract
Colonization of the gastrointestinal (GI) tract with pathogenic bacteria is an important risk factor for the development of certain potentially severe and life-threatening healthcare-associated infections, yet efforts to develop effective decolonization agents have been largely unsuccessful thus far. Herein, we report modification of the 1,2,4-oxadiazole class of antimicrobial compounds with poorly permeable functional groups in order to target bacterial pathogens within the GI tract. We have identified that the quaternary ammonium functionality of analogue 26a results in complete impermeability in Caco-2 cell monolayers while retaining activity against GI pathogens Clostridioides difficile and multidrug-resistant (MDR) Enterococcus faecium. Low compound recovery levels after oral administration in rats were observed, which suggests that the analogues may be susceptible to degradation or metabolism within the gut, highlighting a key area for optimization in future efforts. This study demonstrates that modified analogues of the 1,2,4-oxadiazole class may be potential leads for further development of colon-targeted antimicrobial agents.
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Affiliation(s)
- Noel P. Pitcher
- Medicinal
Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Jitendra R. Harjani
- Medicinal
Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Yichao Zhao
- Medicinal
Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Jianwen Jin
- Medicinal
Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
| | - Daniel R. Knight
- School
of Medical and Health Sciences, Edith Cowan
University, Joondalup, Western Australia 6027, Australia
- School of
Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Queen Elizabeth
II Medical Centre, Nedlands, Western Australia 6009, Australia
- Medical,
Molecular and Forensic Sciences, Murdoch
University, Murdoch, Western Australia 6150, Australia
- Department
of Microbiology, PathWest Laboratory Medicine, Queen Elizabeth II Medical Centre, Nedlands, Western Australia 6009, Australia
| | - Lucy Li
- Department
of Microbiology & Immunology, Peter Doherty Institute for Infection
and Immunity, The University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Papanin Putsathit
- School
of Medical and Health Sciences, Edith Cowan
University, Joondalup, Western Australia 6027, Australia
- School of
Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Queen Elizabeth
II Medical Centre, Nedlands, Western Australia 6009, Australia
- Medical,
Molecular and Forensic Sciences, Murdoch
University, Murdoch, Western Australia 6150, Australia
- Department
of Microbiology, PathWest Laboratory Medicine, Queen Elizabeth II Medical Centre, Nedlands, Western Australia 6009, Australia
| | - Thomas V. Riley
- School
of Medical and Health Sciences, Edith Cowan
University, Joondalup, Western Australia 6027, Australia
- School of
Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Queen Elizabeth
II Medical Centre, Nedlands, Western Australia 6009, Australia
- Medical,
Molecular and Forensic Sciences, Murdoch
University, Murdoch, Western Australia 6150, Australia
- Department
of Microbiology, PathWest Laboratory Medicine, Queen Elizabeth II Medical Centre, Nedlands, Western Australia 6009, Australia
| | - Glen P. Carter
- Department
of Microbiology & Immunology, Peter Doherty Institute for Infection
and Immunity, The University of Melbourne, Melbourne, Victoria 3000, Australia
| | - Jonathan B. Baell
- School
of Pharmaceutical Sciences, Nanjing Tech
University, No. 30 South
Puzhu Road, Nanjing 211816, People’s Republic of China
- Medicinal
Chemistry, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, Victoria 3052, Australia
- Australian
Translational Medicinal Chemistry Facility (ATMCF), Monash University, Parkville, Victoria 3052, Australia
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4
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Deshayes C, Arafath MN, Apaire-Marchais V, Roger E. Drug Delivery Systems for the Oral Administration of Antimicrobial Peptides: Promising Tools to Treat Infectious Diseases. FRONTIERS IN MEDICAL TECHNOLOGY 2022; 3:778645. [PMID: 35146486 PMCID: PMC8821882 DOI: 10.3389/fmedt.2021.778645] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 12/06/2021] [Indexed: 12/12/2022] Open
Abstract
Antimicrobial peptides (AMPs) have a great potential to face the global expansion of antimicrobial resistance (AMR) associated to the development of multidrug-resistant (MDR) pathogens. AMPs are usually composed of 10–50 amino acids with a broad structural diversity and present a range of antimicrobial activities. Unfortunately, even if the oral route is the most convenient one, currently approved therapeutic AMPs are mostly administrated by the intravenous route. Thus, the development of novel drug delivery systems (DDSs) represents a promising opportunity to protect AMPs from chemical and enzymatic degradation through the gastrointestinal tract and to increase intestinal permeability leading to high bioavailability. In this review, the classification and properties as well as mechanisms of the AMPs used in infectiology are first described. Then, the different pharmaceutical forms existing in the market for oral administration are presented. Finally, the formulation technologies, including microparticle- and nanoparticle-based DDSs, used to improve the oral bioavailability of AMPs are reviewed.
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Affiliation(s)
| | | | | | - Emilie Roger
- University of Angers, INSERM, CNRS, MINT, SFR ICAT, Angers, France
- *Correspondence: Emilie Roger
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5
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Kaur J, Cao X, Abutaleb NS, Elkashif A, Graboski AL, Krabill AD, AbdelKhalek AH, An W, Bhardwaj A, Seleem MN, Flaherty DP. Optimization of Acetazolamide-Based Scaffold as Potent Inhibitors of Vancomycin-Resistant Enterococcus. J Med Chem 2020; 63:9540-9562. [PMID: 32787141 DOI: 10.1021/acs.jmedchem.0c00734] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Vancomycin-resistant enterococci (VRE) are the second leading cause of hospital-acquired infections (HAIs) attributed to a drug-resistant bacterium in the United States, and resistance to the frontline treatments is well documented. To combat VRE, we have repurposed the FDA-approved carbonic anhydrase drug acetazolamide to design potent antienterococcal agents. Through structure-activity relationship optimization we have arrived at two leads possessing improved potency against clinical VRE strains from MIC = 2 μg/mL (acetazolamide) to MIC = 0.007 μg/mL (22) and 1 μg/mL (26). Physicochemical properties were modified to design leads that have either high oral bioavailability to treat systemic infections or low intestinal permeability to treat VRE infections in the gastrointestinal tract. Our data suggest the intracellular targets for the molecules are putative α-carbonic and γ-carbonic anhydrases, and homology modeling and molecular dynamics simulations were performed. Together, this study presents potential anti-VRE therapeutic options to provide alternatives for problematic VRE infections.
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Affiliation(s)
- Jatinder Kaur
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, Indiana 47907, United States
| | - Xufeng Cao
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, Indiana 47907, United States
| | - Nader S Abutaleb
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, 625 Harrison Street, West Lafayette, Indiana 47907, United States
| | - Ahmed Elkashif
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, 625 Harrison Street, West Lafayette, Indiana 47907, United States
| | - Amanda L Graboski
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, Indiana 47907, United States
| | - Aaron D Krabill
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, Indiana 47907, United States
| | - Ahmed Hassan AbdelKhalek
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, 625 Harrison Street, West Lafayette, Indiana 47907, United States
| | - Weiwei An
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, Indiana 47907, United States
| | - Atul Bhardwaj
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, Indiana 47907, United States
| | - Mohamed N Seleem
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, 625 Harrison Street, West Lafayette, Indiana 47907, United States.,Purdue Institute for Drug Discovery, 720 Clinic Drive, West Lafayette, Indiana 47907, United States.,Purdue Institute of Inflammation, Immunology and Infectious Disease, 207 South Martin Jischke Drive, West Lafayette, Indiana 47907, United States
| | - Daniel P Flaherty
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, 575 Stadium Mall Drive, West Lafayette, Indiana 47907, United States.,Purdue Institute for Drug Discovery, 720 Clinic Drive, West Lafayette, Indiana 47907, United States.,Purdue Institute of Inflammation, Immunology and Infectious Disease, 207 South Martin Jischke Drive, West Lafayette, Indiana 47907, United States
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6
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Eleraky NE, Allam A, Hassan SB, Omar MM. Nanomedicine Fight against Antibacterial Resistance: An Overview of the Recent Pharmaceutical Innovations. Pharmaceutics 2020; 12:E142. [PMID: 32046289 PMCID: PMC7076477 DOI: 10.3390/pharmaceutics12020142] [Citation(s) in RCA: 127] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 01/29/2020] [Accepted: 02/04/2020] [Indexed: 12/16/2022] Open
Abstract
Based on the recent reports of World Health Organization, increased antibiotic resistance prevalence among bacteria represents the greatest challenge to human health. In addition, the poor solubility, stability, and side effects that lead to inefficiency of the current antibacterial therapy prompted the researchers to explore new innovative strategies to overcome such resilient microbes. Hence, novel antibiotic delivery systems are in high demand. Nanotechnology has attracted considerable interest due to their favored physicochemical properties, drug targeting efficiency, enhanced uptake, and biodistribution. The present review focuses on the recent applications of organic (liposomes, lipid-based nanoparticles, polymeric micelles, and polymeric nanoparticles), and inorganic (silver, silica, magnetic, zinc oxide (ZnO), cobalt, selenium, and cadmium) nanosystems in the domain of antibacterial delivery. We provide a concise description of the characteristics of each system that render it suitable as an antibacterial delivery agent. We also highlight the recent promising innovations used to overcome antibacterial resistance, including the use of lipid polymer nanoparticles, nonlamellar liquid crystalline nanoparticles, anti-microbial oligonucleotides, smart responsive materials, cationic peptides, and natural compounds. We further discuss the applications of antimicrobial photodynamic therapy, combination drug therapy, nano antibiotic strategy, and phage therapy, and their impact on evading antibacterial resistance. Finally, we report on the formulations that made their way towards clinical application.
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Affiliation(s)
- Nermin E. Eleraky
- Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt; (N.E.E.); (A.A.)
| | - Ayat Allam
- Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt; (N.E.E.); (A.A.)
- Assiut International Center of Nanomedicine, Al-Rajhy Liver Hospital, Assiut University, Assiut 71515, Egypt
| | - Sahar B. Hassan
- Department of Clinical pharmacy, Faculty of Pharmacy, Assiut University, Assiut 71526, Egypt;
| | - Mahmoud M. Omar
- Department of Pharmaceutics and Industrial Pharmacy, Deraya University, Minia 61768, Egypt
- Department of Pharmaceutics and Clinical Pharmacy, Faculty of Pharmacy Sohag University, Sohag 82524, Egypt
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7
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Davido B, Moussiegt A, Dinh A, Bouchand F, Matt M, Senard O, Deconinck L, Espinasse F, Lawrence C, Fortineau N, Saleh-Mghir A, Caballero S, Escaut L, Salomon J. Germs of thrones - spontaneous decolonization of Carbapenem-Resistant Enterobacteriaceae (CRE) and Vancomycin-Resistant Enterococci (VRE) in Western Europe: is this myth or reality? Antimicrob Resist Infect Control 2018; 7:100. [PMID: 30123500 PMCID: PMC6090624 DOI: 10.1186/s13756-018-0390-5] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 07/31/2018] [Indexed: 11/16/2022] Open
Abstract
Background In France, Carbapenem-Resistant Enterobacteriaceae (CRE) and Vancomycin-Resistant Enterococci (VRE) are considered as Extensively Drug-Resistant (XDR) bacteria. Their management requires reinforcement of hospital’s hygiene policies, and currently there is few consistent data concerning the spontaneous decolonization in XDR colonized patients. Our aim is to study the natural history of decolonization of XDR carriers over time in a hospital setting in a low prevalence country. Material and methods Retrospective multicenter study over 2 years (2015–2016) in 2 different tertiary care hospital sites and units having an agreement for permanent cohorting of such XDR carriers. We gathered the type of microorganisms, risk factors for colonization and rectal swabs from patient’s follow-up. We also evaluated patient care considering isolation precautions. Results We included 125 patients, aged 63+/−19y, including 72.8% of CRE (n = 91), 24.8% of VRE (n = 31) and 2.4% (n = 3) co-colonized with CRE and VRE. CRE were mainly E. coli (n = 54), K. pneumoniae (n = 51) and E. cloacae (n = 6). Mechanisms of resistance were mainly OXA-48 (n = 69), NDM-1 (n = 11), OXA-232 (n = 8) and KPC (n = 3). Prior antibiotic therapy was reported in 38.4% (n = 48) of cases. Conversely, 17.6% (n = 22) received antibiotics during follow-up. Spontaneous decolonization occurred within the first 30 days in 16.4% (n = 19/116) of cases and up to 48.2% after day-90 with a median follow-up of 96 days (0–974). We estimated that XDR carriage was associated with a larger care burden in 13.6% (n = 17) of cases, especially due to a prolongation of hospitalization of 32.5 days (15–300). Conclusions Our study shows that spontaneous decolonization is increasing over time (up to 48.2%). We can regret that only few patients underwent screening after 1 year, emphasizing the need for more monitoring and prospective studies.
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Affiliation(s)
- Benjamin Davido
- 1Maladies infectieuses, Hôpital Universitaire Raymond-Poincaré, AP-HP, 92380 Garches, France
| | - Aurore Moussiegt
- 1Maladies infectieuses, Hôpital Universitaire Raymond-Poincaré, AP-HP, 92380 Garches, France
| | - Aurélien Dinh
- 1Maladies infectieuses, Hôpital Universitaire Raymond-Poincaré, AP-HP, 92380 Garches, France
| | - Frédérique Bouchand
- 2Pharmacie Hospitalière, Hôpital Universitaire Raymond-Poincaré, AP-HP, 92380 Garches, France
| | - Morgan Matt
- 1Maladies infectieuses, Hôpital Universitaire Raymond-Poincaré, AP-HP, 92380 Garches, France
| | - Olivia Senard
- 1Maladies infectieuses, Hôpital Universitaire Raymond-Poincaré, AP-HP, 92380 Garches, France
| | - Laurene Deconinck
- 1Maladies infectieuses, Hôpital Universitaire Raymond-Poincaré, AP-HP, 92380 Garches, France
| | - Florence Espinasse
- 3Hygiène Hospitalière, Hôpital Universitaire Ambroise-Paré, AP-HP, 92210 Boulogne-Billancourt, France
| | - Christine Lawrence
- 4Hygiène Hospitalière, Hôpital Universitaire Raymond-Poincaré, AP-HP, 92380 Garches, France
| | - Nicolas Fortineau
- 5Laboratoire de Microbiologie, Hôpital Universitaire Kremlin-Bicêtre, AP-HP, 94270 Le Kremlin-Bicêtre, France
| | - Azzam Saleh-Mghir
- 1Maladies infectieuses, Hôpital Universitaire Raymond-Poincaré, AP-HP, 92380 Garches, France
| | | | - Lelia Escaut
- 7Maladies Infectieuses, Hôpital Universitaire Kremlin-Bicêtre, AP-HP, 94270 Le Kremlin-Bicêtre, France
| | - Jérome Salomon
- 1Maladies infectieuses, Hôpital Universitaire Raymond-Poincaré, AP-HP, 92380 Garches, France
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8
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AbdelKhalek A, Abutaleb NS, Mohammad H, Seleem MN. Repurposing ebselen for decolonization of vancomycin-resistant enterococci (VRE). PLoS One 2018; 13:e0199710. [PMID: 29953486 PMCID: PMC6023106 DOI: 10.1371/journal.pone.0199710] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 06/12/2018] [Indexed: 11/18/2022] Open
Abstract
Enterococci represent one of the microbial world's most challenging enigmas. Colonization of the gastrointestinal tract (GIT) of high-risk/immunocompromised patients by enterococci exhibiting resistance to vancomycin (VRE) can lead to life-threating infections, including bloodstream infections and endocarditis. Decolonization of VRE from the GIT of high-risk patients represents an alternative method to suppress the risk of the infection. It could be considered as a preventative measure to protect against VRE infections in high-risk individuals. Though multiple agents (ramoplanin and bacitracin) have been evaluated clinically, no drugs are currently approved for use in VRE decolonization of the GIT. The present study evaluates ebselen, a clinical molecule, for use as a decolonizing agent against VRE. When evaluated against a broad array of enterococcal isolates in vitro, ebselen was found to be as potent as linezolid (minimum inhibitory concentration against 90% of clinical isolates tested was 2 μg/ml). Though VRE has a remarkable ability to develop resistance to antibacterial agents, no resistance to ebselen emerged after a clinical isolate of vancomycin-resistant E. faecium was serially-passaged with ebselen for 14 days. Against VRE biofilm, a virulence factor that enables the bacteria to colonize the gut, ebselen demonstrated the ability to both inhibit biofilm formation and disrupt mature biofilm. Furthermore, in a murine VRE colonization reduction model, ebselen proved as effective as ramoplanin in reducing the bacterial shedding and burden of VRE present in the fecal content (by > 99.99%), cecum, and ileum of mice. Based on the promising results obtained, ebselen warrants further investigation as a novel decolonizing agent to quell VRE infection.
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Affiliation(s)
- Ahmed AbdelKhalek
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, United States of America
| | - Nader S. Abutaleb
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, United States of America
| | - Haroon Mohammad
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, United States of America
| | - Mohamed N. Seleem
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, Indiana, United States of America
- Purdue Institute of Inflammation, Immunology, and Infectious Disease, West Lafayette, Indiana, United States of America
- * E-mail:
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9
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Mohammad H, AbdelKhalek A, Abutaleb NS, Seleem MN. Repurposing niclosamide for intestinal decolonization of vancomycin-resistant enterococci. Int J Antimicrob Agents 2018; 51:897-904. [PMID: 29432868 DOI: 10.1016/j.ijantimicag.2018.02.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2017] [Revised: 01/24/2018] [Accepted: 02/03/2018] [Indexed: 01/07/2023]
Abstract
Enterococci are commensal micro-organisms present in the gastrointestinal tract of humans. Although normally innocuous to the host, strains of enterococcus exhibiting resistance to vancomycin (VRE) have been associated with high rates of infection and mortality in immunocompromised patients. Decolonization of VRE represents a key strategy to curb infection in highly-susceptible patients. However, there is a dearth of decolonizing agents available clinically that are effective against VRE. The present study found that niclosamide, an anthelmintic drug, has potent antibacterial activity against clinical isolates of vancomycin-resistant Enterococcus faecium (minimum inhibitory concentration 1-8 µg/mL). E. faecium mutants exhibiting resistance to niclosamide could not be isolated even after multiple (10) serial passages. Based upon these promising in-vitro results and the limited permeability of niclosamide across the gastrointestinal tract (when administered orally), niclosamide was evaluated in a VRE colonization-reduction murine model. Remarkably, niclosamide outperformed linezolid, an antibiotic used clinically to treat VRE infections. Niclosamide was as effective as ramoplanin in reducing the burden of vancomycin-resistant E. faecium in the faeces, caecal content and ileal content of infected mice after only 8 days of treatment. Linezolid, in contrast, was unable to decrease the burden of VRE in the gastrointestinal tract of mice. The results obtained indicate that niclosamide warrants further evaluation as a novel decolonizing agent to suppress VRE infections.
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Affiliation(s)
- Haroon Mohammad
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA
| | - Ahmed AbdelKhalek
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA
| | - Nader S Abutaleb
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA
| | - Mohamed N Seleem
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA; Purdue Institute of Inflammation, Immunology and Infectious Disease, West Lafayette, IN, USA.
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Molchanova N, Hansen PR, Franzyk H. Advances in Development of Antimicrobial Peptidomimetics as Potential Drugs. Molecules 2017; 22:E1430. [PMID: 28850098 PMCID: PMC6151827 DOI: 10.3390/molecules22091430] [Citation(s) in RCA: 179] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 08/18/2017] [Accepted: 08/22/2017] [Indexed: 01/19/2023] Open
Abstract
The rapid emergence of multidrug-resistant pathogens has evolved into a global health problem as current treatment options are failing for infections caused by pan-resistant bacteria. Hence, novel antibiotics are in high demand, and for this reason antimicrobial peptides (AMPs) have attracted considerable interest, since they often show broad-spectrum activity, fast killing and high cell selectivity. However, the therapeutic potential of natural AMPs is limited by their short plasma half-life. Antimicrobial peptidomimetics mimic the structure and biological activity of AMPs, but display extended stability in the presence of biological matrices. In the present review, focus is on the developments reported in the last decade with respect to their design, synthesis, antimicrobial activity, cytotoxic side effects as well as their potential applications as anti-infective agents. Specifically, only peptidomimetics with a modular structure of residues connected via amide linkages will be discussed. These comprise the classes of α-peptoids (N-alkylated glycine oligomers), β-peptoids (N-alkylated β-alanine oligomers), β³-peptides, α/β³-peptides, α-peptide/β-peptoid hybrids, α/γ N-acylated N-aminoethylpeptides (AApeptides), and oligoacyllysines (OAKs). Such peptidomimetics are of particular interest due to their potent antimicrobial activity, versatile design, and convenient optimization via assembly by standard solid-phase procedures.
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Affiliation(s)
- Natalia Molchanova
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 162, DK-2100 Copenhagen, Denmark.
| | - Paul R Hansen
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 162, DK-2100 Copenhagen, Denmark.
| | - Henrik Franzyk
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Jagtvej 162, DK-2100 Copenhagen, Denmark.
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Impact of faecal microbiota transplantation to eradicate vancomycin-resistant enterococci (VRE) colonization in humans. J Infect 2017; 75:376-377. [PMID: 28601577 DOI: 10.1016/j.jinf.2017.06.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 05/29/2017] [Accepted: 06/01/2017] [Indexed: 11/22/2022]
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Dubberke ER, Mullane KM, Gerding DN, Lee CH, Louie TJ, Guthertz H, Jones C. Clearance of Vancomycin-Resistant Enterococcus Concomitant With Administration of a Microbiota-Based Drug Targeted at Recurrent Clostridium difficile Infection. Open Forum Infect Dis 2016; 3:ofw133. [PMID: 27703995 PMCID: PMC5047394 DOI: 10.1093/ofid/ofw133] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 06/15/2016] [Indexed: 02/06/2023] Open
Abstract
Background. Vancomycin-resistant Enterococcus (VRE) is a major healthcare-associated pathogen and a well known complication among transplant and immunocompromised patients. We report on stool VRE clearance in a post hoc analysis of the Phase 2 PUNCH CD study assessing a microbiota-based drug for recurrent Clostridium difficile infection (CDI). Methods. A total of 34 patients enrolled in the PUNCH CD study received 1 or 2 doses of RBX2660 (microbiota suspension). Patients were requested to voluntarily submit stool samples at baseline and at 7, 30, and 60 days and 6 months after the last administration of RBX2660. Stool samples were tested for VRE using bile esculin azide agar with 6 µg/mL vancomycin and Gram staining. Vancomycin resistance was confirmed by Etest. Results. VRE status (at least 1 test result) was available for 30 patients. All stool samples for 19 patients (63.3%, mean age 61.7 years, 68% female) tested VRE negative. Eleven patients (36.7%, mean age 75.5 years, 64% female) were VRE positive at the first test (baseline or 7-day follow-up). Of these patients, 72.7%, n = 8 converted to negative as of the last available follow-up (30 or 60 days or 6 months). Of the other 3: 1 died (follow-up data not available); 1 patient remained positive at all follow-ups; 1 patient retested positive at 6 months with negative tests during the interim. Conclusions. Although based on a small sample size, this secondary analysis demonstrated the possibility of successfully converting a high percentage of VRE-positive patients to negative in a recurrent CDI population with RBX2660.
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Affiliation(s)
- Erik R Dubberke
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Kathleen M Mullane
- Section of Infectious Diseases and Global Health, University of Chicago Medicine
| | - Dale N Gerding
- Department of Medicine, Loyola University Chicago Stritch School of Medicine, Maywood; Edward Hines Jr. Veterans Affairs Hospital, Hines, Illinois
| | - Christine H Lee
- Department of Medicine, McMaster University, Hamilton, Ontario
| | - Thomas J Louie
- Departments of Medicine and Microbiology-Immunology and Infectious Diseases, University of Calgary, Alberta, Canada
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Cervera C, van Delden C, Gavaldà J, Welte T, Akova M, Carratalà J. Multidrug-resistant bacteria in solid organ transplant recipients. Clin Microbiol Infect 2014; 20 Suppl 7:49-73. [DOI: 10.1111/1469-0691.12687] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 05/16/2014] [Accepted: 05/18/2014] [Indexed: 12/23/2022]
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Kim DH, Kim HK, Kim KM, Kim CK, Jeong MH, Ko CY, Moon KH, Kang JS. Antibacterial activities of macrolactin A and 7-O-succinyl macrolactin A from Bacillus polyfermenticus KJS-2 against vancomycin-resistant enterococci and methicillin-resistant Staphylococcus aureus. Arch Pharm Res 2011; 34:147-52. [PMID: 21468926 DOI: 10.1007/s12272-011-0117-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2010] [Revised: 10/15/2010] [Accepted: 10/18/2010] [Indexed: 11/25/2022]
Abstract
The principal objective of this study was to evaluate the antibacterial activities of macrolactin A (MA) and 7-O-succinyl macrolactin A (SMA) generated from Bacillus polyfermenticus KJS-2 against vancomycin-resistant enterococci (VREs) and methicillin-resistant Staphylococcus aureus. The minimal inhibitory concentrations (MICs) of MA and SMA against VREs were 16 and 2∼1 μg/mL, respectively, and the MICs of MA and SMA against methicillin-resistant Staphylococcus aureus were 2 and < 0.25 μg/mL, respectively. Their MIC values were comparable or superior to those of teicoplanin. In evaluating the inhibitory effects of intestinal VRE colonization in mice, the oral MA and SMA effected a rapid inhibition of intestinal VRE colonization in mice, and the intraperitoneal SMA also inhibited VRE colonization, whereas intraperitoneal MA did not.
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Affiliation(s)
- Dong Hee Kim
- Research and Development Center, Daewoo Pharm. Co. Ltd., Gimhae, Korea
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15
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Abstract
Following the widespread use of immunosuppressive therapy and broad-spectrum antimycotic prophylaxis, C. glabrata has emerged as an important opportunistic pathogen in the oral mucosa. In the past, studies on the virulence factors and host-pathogen interactions of this organism were scarce, but continued to rise in recent years. Denture-wearing, immunosuppression, antibiotic therapy, and aging are risk factors for oral colonization or infection with C. glabrata. Compared with C. albicans, C. glabrata exhibits lower oral keratinocyte-adherence capacity, but higher denture-surface-adherence ability. The role of extracellular hydrolase production in the virulence of this organism does not appear to be as important as it is in C. albicans pathogenesis. Although traditionally thought of as a non-transforming yeast organism, both phenotypic switching and pseudohyphal formation have recently been identified in C. glabrata, but their role in pathogenesis is not known. With the exception of granulocyte monocyte colony-stimulating factor, C. glabrata triggers a lower proinflammatory cytokine response in oral epithelial cells than does C. albicans, in a strain-dependent manner. C. glabrata is less susceptible to killing by human beta-defensins than is C. albicans and exhibits various degrees of resistance to the antifungal activity of salivary histatins and mucins. In addition, C. glabrata possesses both innate and acquired resistance against antifungal drugs, due to its ability to modify ergosterol biosynthesis, mitochondrial function, or antifungal efflux. This resistance allows for its relative overgrowth over other susceptible species and may contribute to the recent emergence of C. glabrata infections in chronically immunocompromised populations. Further investigations on the virulence and host-pathogen interactions of C. glabrata are needed to better define the pathogenesis of oral C. glabrata infection in susceptible hosts.
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Affiliation(s)
- L Li
- Department of Oral Health and Diagnostic Sciences, School of Dental Medicine, University of Connecticut, Farmington, CT 06030-1710, USA
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Paterson DL, Stiefel U, Donskey CJ. Effect of a selective decontamination of the digestive tract regimen including parenteral cefepime on establishment of intestinal colonization with vancomycin-resistant Enterococcus spp. and Klebsiella pneumoniae in mice. Antimicrob Agents Chemother 2006; 50:2537-40. [PMID: 16801439 PMCID: PMC1489767 DOI: 10.1128/aac.00071-06] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
In mice, a selective decontamination of the digestive tract regimen consisting of orogastric tobramycin, polymyxin E, and amphotericin B in combination with subcutaneous cefepime inhibited gram-negative bacilli, including Klebsiella pneumoniae, and did not promote vancomycin-resistant Enterococcus spp. (VRE) colonization. However, concurrent administration of subcutaneous ampicillin-sulbactam resulted in promotion of VRE.
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Affiliation(s)
- David L Paterson
- Division of Infectious Diseases, University of Pittsburg Medical Center, Pittsburg Pennslyvania, USA
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Freeman J, Baines SD, Jabes D, Wilcox MH. Comparison of the efficacy of ramoplanin and vancomycin in both in vitro and in vivo models of clindamycin-induced Clostridium difficile infection. J Antimicrob Chemother 2005; 56:717-25. [PMID: 16143709 DOI: 10.1093/jac/dki321] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
OBJECTIVES Treatment of Clostridium difficile infection (CDI) is limited primarily to either metronidazole or vancomycin. We compared vancomycin and a novel glycolipodepsipeptide, ramoplanin, in both hamster and in vitro gut models of clindamycin-induced CDI. METHODS We used an in vitro triple-stage chemostat model that simulates the human gut, and an in vivo hamster model, both primed with clindamycin. RESULTS Clindamycin exposure elicited symptomatic disease in the hamster model, and promoted C. difficile germination and toxin production in the gut model. C. difficile germination and toxin production were not associated with depletion of gut microflora in the gut model, but were temporarily associated with subinhibitory concentrations of clindamycin. Both ramoplanin and vancomycin were associated with rapid symptom resolution in the hamster model, and rapid toxin titre decrease in the in vitro gut model. In both models of CDI, vancomycin was associated with greater persistence of C. difficile spores. C. difficile spores were recovered significantly more often from the caecal contents of vancomycin-treated (n = 19/23) compared with ramoplanin-treated (n = 6/23) hamsters (P < 0.05). CONCLUSIONS Results from the in vitro gut and hamster models were concordant. Ramoplanin and vancomycin were similarly effective at reducing cytotoxin production in the gut CDI model and in resolving symptoms in the hamster model. Ramoplanin may be more effective than vancomycin at killing spores and preventing spore recrudescence. These findings suggest a potential therapeutic role for ramoplanin in CDI that requires further clinical investigation.
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Affiliation(s)
- Jane Freeman
- Department of Microbiology, University of Leeds and The General Infirmary, Old Medical School, Leeds, LS1 3EX, UK
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Abstract
OBJECTIVE To review the pharmacology, antimicrobial activity, pharmacokinetics, clinical applications, and safety of ramoplanin, a lipoglycodepsipeptide antibiotic. DATA SOURCES Information was obtained from MEDLINE and BIOSIS databases (1984-August 2004) and Oscient Pharmaceuticals using the key words ramoplanin, A 16686, A 16686A, and MDL 62198. STUDY SELECTION AND DATA EXTRACTION Available English-based articles and abstracts were reviewed, along with information from Oscient Pharmaceuticals. DATA SYNTHESIS Ramoplanin exerts its bactericidal activity against gram-positive aerobic and anaerobic bacteria by blocking peptidoglycan synthesis via lipid II. In vitro susceptibility reports have demonstrated efficacy against antibiotic-resistant gram-positive pathogens. Cross-resistance has not been documented with vancomyin and other glycopeptides. Clinical trials are investigating ramoplanin's oral administration for treatment of Clostridium difficile-associated diarrhea. Previous clinical trials had evaluated the suppression of colonization of vancomycin-resistant Enterococcus with ramoplanin. Adverse effects are minimal, and drug-drug interactions have not been documented. CONCLUSIONS The completion of clinical trials will determine whether ramoplanin has a promising role as a treatment option for diarrhea due to C. difficile.
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Affiliation(s)
- Debra K Farver
- College of Pharmacy, South Dakota State University, Yankton, SD 57078-7600, USA.
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Abstract
PURPOSE OF REVIEW This article reviews recent publications regarding new antimicrobial drugs for the treatment of vancomycin-resistant enterococci. RECENT FINDINGS Newer drugs against vancomycin-resistant enterococci are now available or will soon be available. Quinupristin-dalfopristin, a streptogramin, and linezolid, an oxazolidinone, are effective and safe but only bacteriostatic against enterococi. Bacterial isolates resistant to either antibiotic have been described. Daptomycin, a lipopeptide antimicrobial, has good in-vitro bactericidal activity against enterococci, but very limited clinical data exist regarding the treatment of serious enterococcal infection with this compound. Ramoplanin, the first glycolipodepsipeptide antimicrobial in clinical trials, is not systemically absorbed after oral administration, and is being evaluated for the prevention of bloodstream infection in patients colonized with vancomycin-resistant enterococci. Oritavancin and dalbavancin (both glycopeptides) and tigecycline (a monocycline derivative) are being evaluated in phase II and III trials and are not yet commercially available. SUMMARY Treatment of vancomycin-resistant enterococci continues to be problematical although these new drugs offer some hope. The rational use of antibiotics, strict guidelines for the use of new compounds, and adherence to infection control practices continue to be essential components of the management of vancomycin-resistant enterococci colonization and infection.
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Affiliation(s)
- Carlos Torres-Viera
- Yale New Haven Hospital and Department of Medicine, Section of Infectious Diseases, Yale University School of Medicine, New Haven, Connecticut 06504, USA.
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Stiefel U, Donskey CJ. The Role of the Intestinal Tract As a Source for Transmission of Nosocomial Pathogens. Curr Infect Dis Rep 2004; 6:420-425. [PMID: 15538978 DOI: 10.1007/s11908-004-0060-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The intestinal tract provides an important source for transmission of many nosocomial pathogens, including Enterococcus species, Clostridium difficile, Candida species, Enterobacteriaceae, and other gram-negative bacilli. Recent data suggest that the intestinal tracts of hospitalized patients may also be an important reservoir of Staphylococcus aureus. Although the clinical manifestations of these pathogens are diverse, a common pathogenesis is involved in their colonization of and dissemination from the intestinal tract. Of particular importance is the role that antibiotic selective pressure plays in promotion of colonization by antibiotic-resistant pathogens. Strategies to limit the spread of these pathogens must include efforts to improve adherence to standard infection control practices and promotion of good antimicrobial stewardship. New strategies that include application of novel technologies to the problem of pathogen transmission are needed, and additional research is needed to clarify the potential utility of selective decontamination of the digestive tract.
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Affiliation(s)
- Usha Stiefel
- Research Service, Louis Stokes Cleveland Veterans Affairs Medical Center, 10701 East Boulevard, Cleveland, OH 44106, USA.
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