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She P, Yang Y, Li L, Li Y, Liu S, Li Z, Zhou L, Wu Y. Repurposing of the antimalarial agent tafenoquine to combat MRSA. mSystems 2023; 8:e0102623. [PMID: 38047647 PMCID: PMC10734505 DOI: 10.1128/msystems.01026-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Accepted: 10/25/2023] [Indexed: 12/05/2023] Open
Abstract
IMPORTANCE This study represents the first investigation into the antimicrobial effect of TAF against S. aureus and its potential mechanisms. Our data highlighted the effects of TAF against MRSA planktonic cells, biofilms, and persister cells, which is conducive to broadening the application of TAF. Through mechanistic studies, we revealed that TAF targets bacterial cell membranes. In addition, the in vivo experiments in mice demonstrated the safety and antimicrobial efficacy of TAF, suggesting that TAF could be a potential antibacterial drug candidate for the treatment of infections caused by multiple drug-resistant S. aureus.
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Affiliation(s)
- Pengfei She
- Department of Laboratory Medicine, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Yifan Yang
- Department of Laboratory Medicine, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Linhui Li
- Department of Laboratory Medicine, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Yimin Li
- Department of Laboratory Medicine, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Shasha Liu
- Department of Laboratory Medicine, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Zehao Li
- Department of Laboratory Medicine, The Third Xiangya Hospital of Central South University, Changsha, China
| | - Linying Zhou
- Department of Laboratory Medicine, The Affiliated Changsha Hospital of Xiangya School of Medicine (The First Hospital of Changsha), Central South University, Changsha, China
| | - Yong Wu
- Department of Laboratory Medicine, The Affiliated Changsha Hospital of Xiangya School of Medicine (The First Hospital of Changsha), Central South University, Changsha, China
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Venkateswaran P, Vasudevan S, David H, Shaktivel A, Shanmugam K, Neelakantan P, Solomon AP. Revisiting ESKAPE Pathogens: virulence, resistance, and combating strategies focusing on quorum sensing. Front Cell Infect Microbiol 2023; 13:1159798. [PMID: 37457962 PMCID: PMC10339816 DOI: 10.3389/fcimb.2023.1159798] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 06/08/2023] [Indexed: 07/18/2023] Open
Abstract
The human-bacterial association is long-known and well-established in terms of both augmentations of human health and attenuation. However, the growing incidents of nosocomial infections caused by the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter sp.) call for a much deeper understanding of these organisms. Adopting a holistic approach that includes the science of infection and the recent advancements in preventing and treating infections is imperative in designing novel intervention strategies against ESKAPE pathogens. In this regard, this review captures the ingenious strategies commissioned by these master players, which are teamed up against the defenses of the human team, that are equally, if not more, versatile and potent through an analogy. We have taken a basketball match as our analogy, dividing the human and bacterial species into two teams playing with the ball of health. Through this analogy, we make the concept of infectious biology more accessible.
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Affiliation(s)
- Parvathy Venkateswaran
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Sahana Vasudevan
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Helma David
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Adityan Shaktivel
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Karthik Shanmugam
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
| | - Prasanna Neelakantan
- Division of Restorative Dental Sciences, Faculty of Dentistry, The University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Adline Princy Solomon
- Quorum Sensing Laboratory, Centre for Research in Infectious Diseases (CRID), School of Chemical and Biotechnology, SASTRA Deemed to be University, Thanjavur, India
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3
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Nandhini P, Gupta PK, Mahapatra AK, Das AP, Agarwal SM, Mickymaray S, Alothaim AS, Rajan M. In-Silico molecular screening of natural compounds as a potential therapeutic inhibitor for Methicillin-resistant Staphylococcus aureus inhibition. Chem Biol Interact 2023; 374:110383. [PMID: 36754228 DOI: 10.1016/j.cbi.2023.110383] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 12/27/2022] [Accepted: 02/04/2023] [Indexed: 02/08/2023]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a life-threatening superbug causing infectious diseases such as pneumonia, endocarditis, osteomyelitis, etc. Conventional antibiotics are ineffective against MRSA infections due to their resistance mechanism against the antibiotics. The Penicillin Binding Protein (PBP2a) inhibits the activity of antibiotics by hydrolyzing the β-lactam ring. Thus, alternate treatment methods are needed for the treatment of MRSA infections. Natural bioactive compounds exhibit good inhibition efficiency against MRSA infections by hindering its enzymatic mechanism, efflux pump system, etc. The present work deals with identifying potential and non-toxic natural bioactive compounds (ligands) through molecular docking studies through StarDrop software. Various natural bioactive compounds which are effective against MRSA infections were docked with the protein (6VVA). The ligands having good binding energy values and pharmacokinetic and drug-likeness properties have been illustrated as potential ligands for treating MRSA infections. From this exploration, Luteolin, Kaempferol, Chlorogenic acid, Sinigrin, Zingiberene, 1-Methyl-4-(6-methylhepta-1,5-dien-2-yl)cyclohex-1-ene, and Curcumin have found with good binding energies of -8.6 kcal/mol, -8.4 kcal/mol, -8.2 kcal/mol, -7.5 kcal/mol, -7.4 kcal/mol, -7.3 kcal/mol, and -7.2 kcal/mol, respectively.
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Affiliation(s)
- Palanichamy Nandhini
- Biomaterials in Medicinal Chemistry Laboratory, Department of Natural Products Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai-625021, India
| | - Prashant Kr Gupta
- Ayurinformatics Laboratory, Department of Kaumarbhritya, All India Institute of Ayurveda, Sarita Vihar, New Delhi, India
| | - Arun Kumar Mahapatra
- Ayurinformatics Laboratory, Department of Kaumarbhritya, All India Institute of Ayurveda, Sarita Vihar, New Delhi, India
| | - Agneesh Pratim Das
- ICMR-National Institute of Cancer Prevention and Research, I-7, Sector-39, Noida-201301, India
| | - Subhash Mohan Agarwal
- ICMR-National Institute of Cancer Prevention and Research, I-7, Sector-39, Noida-201301, India
| | - Suresh Mickymaray
- Department of Biology, College of Science, Al-Zulfi, Majmaah University, Majmaah-11952, Saudi Arabia
| | - Abdulaziz S Alothaim
- Department of Biology, College of Science, Al-Zulfi, Majmaah University, Majmaah-11952, Saudi Arabia
| | - Mariappan Rajan
- Biomaterials in Medicinal Chemistry Laboratory, Department of Natural Products Chemistry, School of Chemistry, Madurai Kamaraj University, Madurai-625021, India.
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Post-discharge decolonization of patients harboring methicillin-resistant Staphylococcus aureus (MRSA) USA300 strains: secondary analysis of the CLEAR Trial. Infect Control Hosp Epidemiol 2023; 44:315-318. [PMID: 34913422 DOI: 10.1017/ice.2021.482] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The CLEAR Trial recently found that decolonization reduced infections and hospitalizations in MRSA carriers in the year following hospital discharge. In this secondary analysis, we explored whether decolonization had a similar benefit in the subgroup of trial participants who harbored USA300, using two different definitions for the USA300 strain-type.
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Chesdachai S, Baddour LM, Sohail MR, Palraj BR, Madhavan M, Tabaja H, Fida M, Lahr BD, DeSimone DC. Evaluation of EHRA Consensus in Patients with Cardiovascular Implantable Electronic Devices and Staphylococcus aureus Bacteremia. Heart Rhythm 2021; 19:570-577. [DOI: 10.1016/j.hrthm.2021.12.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 12/11/2022]
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6
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Daptomycin versus Vancomycin for the Treatment of Methicillin-Resistant Staphylococcus aureus Bloodstream Infection with or without Endocarditis: A Systematic Review and Meta-Analysis. Antibiotics (Basel) 2021; 10:antibiotics10081014. [PMID: 34439067 PMCID: PMC8389004 DOI: 10.3390/antibiotics10081014] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/05/2021] [Accepted: 08/19/2021] [Indexed: 12/29/2022] Open
Abstract
Background: Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of invasive infections, mainly bloodstream infections (BSI) with or without endocarditis. The purpose of this meta-analysis was to compare vancomycin, the mainstay treatment, with daptomycin as therapeutic options in this context. Materials: PubMed, Embase and the Cochrane Database were searched from their inception to 15 February 2020. The primary outcome was all-cause mortality. Secondary outcomes included clinical failure, infection recurrence, persistence of infection, length-of-stay, antibiotic discontinuation due to adverse events (AEs) and 30-day re-admission. This study was registered with PROSPERO, CRD42020169413. Results: Eight studies (1226 patients, 554 vs. 672 in daptomycin vs. vancomycin, respectively) were included. No significant difference in terms of overall mortality was observed [odds ratio (OR) 0.73, 95% confidence interval (CI) 0.40–1.33, I2 = 67%]. Daptomycin was associated with a significantly reduced risk of clinical failure (OR 0.58, 95% CI 0.38–0.89, I2 = 60%), as confirmed by pooling adjusted effect sizes (adjusted OR against the use of vancomycin 1.94, 95%CI 1.33–1.82, I2 = 41%), and was linked with fewer treatment-limiting AEs (OR 0.15, 95%CI 0.06–0.36, I2 = 19%). No difference emerged between the two treatments as secondary outcomes. Results were not robust to unmeasured confounding (E-value lower than 95% CI 1.00 for all-cause mortality). Conclusions: Against MRSA BSI, with or without endocarditis, daptomycin seems to be associated with a lower risk of clinical failure and treatment-limiting AEs compared with vancomycin. Further studies are needed to better characterize the differences between the two drugs.
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Souli M, Ruffin F, Choi SH, Park LP, Gao S, Lent NC, Sharma-Kuinkel BK, Thaden JT, Maskarinec SA, Wanda L, Hill-Rorie J, Warren B, Hansen B, Fowler VG. Changing Characteristics of Staphylococcus aureus Bacteremia: Results From a 21-Year, Prospective, Longitudinal Study. Clin Infect Dis 2020; 69:1868-1877. [PMID: 31001618 DOI: 10.1093/cid/ciz112] [Citation(s) in RCA: 74] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Accepted: 02/21/2019] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND We conducted a longitudinal study to evaluate changes in the clinical presentation and epidemiology of Staphylococcus aureus bacteremia (SAB) in an academic, US medical center. METHODS Consecutive patients with monomicrobial SAB were enrolled from January 1995 to December 2015. Each person's initial bloodstream S. aureus isolate was genotyped using spa typing. Clonal complexes (CCs) were assigned using Ridom StaphType software. Changes over time in both the patient and bacterial characteristics were estimated with linear regression. Associations between genotypes or clinical characteristics and complications were estimated using multivariable regression models. RESULTS Among the 2348 eligible participants, 54.2% had an implantable, foreign body of some type. This proportion increased significantly during the 21-year study period, by 0.96% annually (P = .002), as did comorbid conditions and acquisition outside of the hospital. Rates of any metastatic complication also significantly increased, by 0.94% annually (P = .019). Among the corresponding bloodstream S. aureus isolates, spa-CC012 (multi-locus sequence type [MLST] CC30), -CC004 (MLST CC45), -CC189 (MLST CC1), and -CC084 (MLST CC15) all significantly declined during the study period, while spa-CC008 (MLST CC8) significantly increased. Patients with SAB due to spa-CC008 were significantly more likely to develop metastatic complications in general, and abscesses, septic emboli, and persistent bacteremia in particular. After adjusting for demographic, racial, and clinical variables, the USA300 variant of spa-CC008 was independently associated with metastatic complications (odds ratio 1.42; 95% confidence interval 1.02-1.99). CONCLUSIONS Systematic approaches for monitoring complications of SAB and genotyping the corresponding bloodstream isolates will help identify the emergence of hypervirulent clones and likely improve clinical management of this syndrome.
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Affiliation(s)
- Maria Souli
- Department of Medicine, Duke University Medical Center, North Carolina.,Duke Clinical Research Institute, Durham, North Carolina.,Fourth Department of Internal Medicine, National and Kapodistrian University of Athens School of Medicine, Greece
| | - Felicia Ruffin
- Department of Medicine, Duke University Medical Center, North Carolina
| | - Seong-Ho Choi
- Department of Medicine, Duke University Medical Center, North Carolina.,Department of Internal Medicine, Division of Infectious Diseases, Chung-Ang University College of Medicine, Seoul, South Korea
| | - Lawrence P Park
- Department of Medicine, Duke University Medical Center, North Carolina.,Duke Global Health Institute, Duke University, Durham, North Carolina
| | - Shengli Gao
- Department of Medicine, Duke University Medical Center, North Carolina.,The First People's Hospital of Wujiang District, Suzhou City, Jiangsu Province, China
| | | | | | - Joshua T Thaden
- Department of Medicine, Duke University Medical Center, North Carolina
| | | | - Lisa Wanda
- Department of Medicine, Duke University Medical Center, North Carolina.,School of Medicine, University of North Carolina, Chapel Hill
| | - Jonathan Hill-Rorie
- Department of Medicine, Duke University Medical Center, North Carolina.,Harvard T. H. Chan School of Public Health, Boston, Massachusetts
| | - Bobby Warren
- Department of Medicine, Duke University Medical Center, North Carolina
| | - Brenda Hansen
- Department of Medicine, Duke University Medical Center, North Carolina.,Pediatric Gastroenterology, University of North Carolina, Chapel Hill
| | - Vance G Fowler
- Department of Medicine, Duke University Medical Center, North Carolina.,Duke Clinical Research Institute, Durham, North Carolina
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8
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Glycosylation-dependent opsonophagocytic activity of staphylococcal protein A antibodies. Proc Natl Acad Sci U S A 2020; 117:22992-23000. [PMID: 32855300 PMCID: PMC7502815 DOI: 10.1073/pnas.2003621117] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
All currently licensed antibodies against bacteria target exotoxins. For most pathogens, neutralization of toxin(s) is not sufficient to prevent bacterial replication. Antibodies against surface determinants represent better candidates to enhance opsonophagocytic killing, but the mechanisms of action of such antibodies have not been systematically studied. Staphylococcal protein A is a conserved surface protein of Staphylococcus aureus and a crucial virulence determinant that manipulates B-cell responses and blocks deposition of opsonin. Monoclonal antibodies directed against SpA represent potential therapeutic agents as well as a formidable tool to identify and optimize effector functions of antibodies that can promote bacterial clearance. Antibodies may bind to bacterial pathogens or their toxins to control infections, and their effector activity is mediated through the recruitment of complement component C1q or the engagement with Fcγ receptors (FcγRs). For bacterial pathogens that rely on a single toxin to cause disease, immunity correlates with toxin neutralization. Most other bacterial pathogens, including Staphylococcus aureus, secrete numerous toxins and evolved multiple mechanisms to escape opsonization and complement killing. Several vaccine candidates targeting defined surface antigens of S. aureus have failed to meet clinical endpoints. It is unclear that such failures can be solely attributed to the poor selection of antibody targets. Thus far, studies to delineate antibody-mediated uptake and killing of Gram-positive pathogens remain extremely limited. Here, we exploit 3F6-hIgG1, a human monoclonal antibody that binds and neutralizes the abundant surface-exposed Staphylococcal protein A (SpA). We find that galactosylation of 3F6-hIgG1 that favors C1q recruitment is indispensable for opsonophagocytic killing of staphylococci and for protection against bloodstream infection in animals. However, the simple removal of fucosyl residues, which results in reduced C1q binding and increased engagement with FcγR, maintains the opsonophagocytic killing and protective attributes of the antibody. We confirm these results by engineering 3F6-hIgG1 variants with biased binding toward C1q or FcγRs. While the therapeutic benefit of monoclonal antibodies against infectious disease agents may be debatable, the functional characterization of such antibodies represents a powerful tool for the development of correlates of protection that may guide future vaccine trials.
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9
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Guo Y, Song G, Sun M, Wang J, Wang Y. Prevalence and Therapies of Antibiotic-Resistance in Staphylococcus aureus. Front Cell Infect Microbiol 2020; 10:107. [PMID: 32257966 PMCID: PMC7089872 DOI: 10.3389/fcimb.2020.00107] [Citation(s) in RCA: 333] [Impact Index Per Article: 83.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 02/27/2020] [Indexed: 12/17/2022] Open
Abstract
Infectious diseases are the second most important cause of human death worldwide; Staphylococcus aureus (S. aureus) is a very common human pathogenic microorganism that can trigger a variety of infectious diseases, such as skin and soft tissue infections, endocarditis, osteomyelitis, bacteremia, and lethal pneumonia. Moreover, according to the sensitivity to antibiotic drugs, S. aureus can be divided into methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA). In recent decades, due to the evolution of bacteria and the abuse of antibiotics, the drug resistance of S. aureus has gradually increased, the infection rate of MRSA has increased worldwide, and the clinical anti-infective treatment for MRSA has become more difficult. Accumulating evidence has demonstrated that the resistance mechanisms of S. aureus are very complex, especially for MRSA, which is resistant to many kinds of antibiotics. Therefore, understanding the drug resistance of MRSA in a timely manner and elucidating its drug resistance mechanism at the molecular level are of great significance for the treatment of S. aureus infection. A large number of researchers believe that analyzing the molecular characteristics of S. aureus can help provide a basis for designing effective prevention and treatment measures against hospital infections caused by S. aureus and further monitor the evolution of S. aureus. This paper reviews the research status of MSSA and MRSA, the detailed mechanisms of the intrinsic antibiotic resistance and the acquired antibiotic resistance, the advanced research on anti-MRSA antibiotics and novel therapeutic strategies for MRSA treatment.
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Affiliation(s)
- Yunlei Guo
- Department of Endocrinology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Guanghui Song
- Department of Clinical Laboratory, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Meiling Sun
- Department of Clinical Laboratory, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Juan Wang
- Department of Clinical Laboratory, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yi Wang
- Department of Clinical Laboratory, The Affiliated Hospital of Qingdao University, Qingdao, China
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10
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Guo Y, Song G, Sun M, Wang J, Wang Y. Prevalence and Therapies of Antibiotic-Resistance in Staphylococcus aureus. Front Cell Infect Microbiol 2020; 10:107. [PMID: 32257966 DOI: 10.3389/fcimb.2020.00107/bibtex] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 02/27/2020] [Indexed: 05/20/2023] Open
Abstract
Infectious diseases are the second most important cause of human death worldwide; Staphylococcus aureus (S. aureus) is a very common human pathogenic microorganism that can trigger a variety of infectious diseases, such as skin and soft tissue infections, endocarditis, osteomyelitis, bacteremia, and lethal pneumonia. Moreover, according to the sensitivity to antibiotic drugs, S. aureus can be divided into methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA). In recent decades, due to the evolution of bacteria and the abuse of antibiotics, the drug resistance of S. aureus has gradually increased, the infection rate of MRSA has increased worldwide, and the clinical anti-infective treatment for MRSA has become more difficult. Accumulating evidence has demonstrated that the resistance mechanisms of S. aureus are very complex, especially for MRSA, which is resistant to many kinds of antibiotics. Therefore, understanding the drug resistance of MRSA in a timely manner and elucidating its drug resistance mechanism at the molecular level are of great significance for the treatment of S. aureus infection. A large number of researchers believe that analyzing the molecular characteristics of S. aureus can help provide a basis for designing effective prevention and treatment measures against hospital infections caused by S. aureus and further monitor the evolution of S. aureus. This paper reviews the research status of MSSA and MRSA, the detailed mechanisms of the intrinsic antibiotic resistance and the acquired antibiotic resistance, the advanced research on anti-MRSA antibiotics and novel therapeutic strategies for MRSA treatment.
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Affiliation(s)
- Yunlei Guo
- Department of Endocrinology, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Guanghui Song
- Department of Clinical Laboratory, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Meiling Sun
- Department of Clinical Laboratory, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Juan Wang
- Department of Clinical Laboratory, The Affiliated Hospital of Qingdao University, Qingdao, China
| | - Yi Wang
- Department of Clinical Laboratory, The Affiliated Hospital of Qingdao University, Qingdao, China
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11
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Welch D, Buonanno M, Shuryak I, Randers-Pehrson G, Spotnitz HM, Brenner DJ. Effect of far ultraviolet light emitted from an optical diffuser on methicillin-resistant Staphylococcus aureus in vitro. PLoS One 2018; 13:e0202275. [PMID: 30096188 PMCID: PMC6086454 DOI: 10.1371/journal.pone.0202275] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 07/31/2018] [Indexed: 11/19/2022] Open
Abstract
Drug-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) are a target for new antimicrobial technologies. Far-UVC technology is an emerging disinfection method that directly kills microorganisms using light. In contrast with conventional UV sterilization, far-UVC light has antimicrobial capabilities without apparent harm to mammalian cells. This study examines the application of 224 nm far-UVC light delivered from a laser using an optical diffuser towards the goal of protecting against bacterial invasion around skin penetrating devices. Delivery of far-UVC using a laser and optical fibers enables exposure to unique geometries that would otherwise be shielded when using a lamp. Testing of the bactericidal potential of diffusing the far-UVC laser output over a large area was tested and yielded qualitative area killing results. The killing of MRSA using this method was also examined using an in vitro survival assay. Results followed a classic log-linear disinfection model with a rate constant of k = 0.51 cm2/mJ, which corresponds to an inactivation cross section of D90 = 4.5 mJ/cm2. This study establishes far-UVC delivered from a laser through an optical diffuser as a viable solution for disinfection of susceptible regions such as around catheters, drivelines, or other skin penetrating medical devices.
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Affiliation(s)
- David Welch
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York, United States of America
- * E-mail:
| | - Manuela Buonanno
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Igor Shuryak
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Gerhard Randers-Pehrson
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York, United States of America
| | - Henry M. Spotnitz
- Department of Surgery, Columbia University Irving Medical Center, New York, New York, United States of America
| | - David J. Brenner
- Center for Radiological Research, Columbia University Irving Medical Center, New York, New York, United States of America
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12
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Draft Genome Sequence of USA100 Methicillin-Resistant Staphylococcus aureus Strain 209. GENOME ANNOUNCEMENTS 2018; 6:6/1/e01399-17. [PMID: 29301880 PMCID: PMC5754489 DOI: 10.1128/genomea.01399-17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
USA100 strains are significant contributors to the overall burden of health care-associated methicillin-resistant Staphylococcus aureus (MRSA) infections. Strain 209 is a representative MRSA isolate that serves as a model organism for agr type II studies and USA100 virulence assessments. We present a draft genome sequence of this strain.
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13
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Turnbull IR, Buckman SA, Horn CB, Bochicchio GV, Mazuski JE. Antibiotic-Impregnated Central Venous Catheters Do Not Change Antibiotic Resistance Patterns. Surg Infect (Larchmt) 2017; 19:40-47. [PMID: 29028461 DOI: 10.1089/sur.2017.087] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Antibiotic-impregnated central venous catheters (CVCs) decrease the incidence of infection in high-risk patients. However, use of these catheters carries the hypothetical risk of inducing antibiotic resistance. We hypothesized that routine use of minocycline and rifampin-impregnated catheters (MR-CVC) in a single intensive care unit (ICU) would change the resistance profile for Staphylococcus aureus. METHODS We reviewed antibiotic susceptibilities of S. aureus isolates obtained from blood cultures in a large urban teaching hospital from 2002-2015. Resistance patterns were compared before and after implementation of MR-CVC use in the surgical ICU (SICU) in August 2006. We also compared resistance patterns of S. aureus obtained in other ICUs and in non-ICU patients, in whom MR-CVCs were not used. RESULTS Data for rifampin, oxacillin, and clindamycin were available for 9,703 cultures; tetracycline resistance data were available for 4,627 cultures. After implementation of MR-CVC use in the SICU, rifampin resistance remained unchanged, with rates the same as in other ICU and non-ICU populations (3%). After six years of use of MR-CVCs in the SICU, the rate of tetracycline resistance was unchanged in all facilities (1%-3%). The use of MR-CVCs was not associated with any change in S. aureus oxacillin-resistance rates in the SICU (66% vs. 60%). However, there was a significant decrease in S. aureus clindamycin resistance (59% vs. 34%; p < 0.05) in SICU patients. CONCLUSIONS Routine use of rifampin-minocycline-impregnated CVCs in the SICU was not associated with increased resistance of S. aureus isolates to rifampin or tetracyclines.
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Affiliation(s)
- Isaiah R Turnbull
- Department of Surgery, Washington University School of Medicine , St. Louis, Missouri
| | - Sara A Buckman
- Department of Surgery, Washington University School of Medicine , St. Louis, Missouri
| | - Christopher B Horn
- Department of Surgery, Washington University School of Medicine , St. Louis, Missouri
| | - Grant V Bochicchio
- Department of Surgery, Washington University School of Medicine , St. Louis, Missouri
| | - John E Mazuski
- Department of Surgery, Washington University School of Medicine , St. Louis, Missouri
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14
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Buonanno M, Ponnaiya B, Welch D, Stanislauskas M, Randers-Pehrson G, Smilenov L, Lowy FD, Owens DM, Brenner DJ. Germicidal Efficacy and Mammalian Skin Safety of 222-nm UV Light. Radiat Res 2017; 187:483-491. [PMID: 28225654 DOI: 10.1667/rr0010cc.1] [Citation(s) in RCA: 138] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
We have previously shown that 207-nm ultraviolet (UV) light has similar antimicrobial properties as typical germicidal UV light (254 nm), but without inducing mammalian skin damage. The biophysical rationale is based on the limited penetration distance of 207-nm light in biological samples (e.g. stratum corneum) compared with that of 254-nm light. Here we extended our previous studies to 222-nm light and tested the hypothesis that there exists a narrow wavelength window in the far-UVC region, from around 200-222 nm, which is significantly harmful to bacteria, but without damaging cells in tissues. We used a krypton-chlorine (Kr-Cl) excimer lamp that produces 222-nm UV light with a bandpass filter to remove the lower- and higher-wavelength components. Relative to respective controls, we measured: 1. in vitro killing of methicillin-resistant Staphylococcus aureus (MRSA) as a function of UV fluence; 2. yields of the main UV-associated premutagenic DNA lesions (cyclobutane pyrimidine dimers and 6-4 photoproducts) in a 3D human skin tissue model in vitro; 3. eight cellular and molecular skin damage endpoints in exposed hairless mice in vivo. Comparisons were made with results from a conventional 254-nm UV germicidal lamp used as positive control. We found that 222-nm light kills MRSA efficiently but, unlike conventional germicidal UV lamps (254 nm), it produces almost no premutagenic UV-associated DNA lesions in a 3D human skin model and it is not cytotoxic to exposed mammalian skin. As predicted by biophysical considerations and in agreement with our previous findings, far-UVC light in the range of 200-222 nm kills bacteria efficiently regardless of their drug-resistant proficiency, but without the skin damaging effects associated with conventional germicidal UV exposure.
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Affiliation(s)
| | | | - David Welch
- a Center for Radiological Research, Departments of
| | | | | | | | | | - David M Owens
- b Dermatology.,d Pathology and Cell Biology, Columbia University Medical Center, New York, New York
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Phenotypes and Virulence among Staphylococcus aureus USA100, USA200, USA300, USA400, and USA600 Clonal Lineages. mSphere 2016; 1:mSphere00071-16. [PMID: 27303750 PMCID: PMC4899884 DOI: 10.1128/msphere.00071-16] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 05/16/2016] [Indexed: 11/29/2022] Open
Abstract
S. aureus is the leading cause of infective endocarditis in the developed world, affecting ~40,000 individuals each year in the United States, and the second leading cause of bacteremia (D. R. Murdoch et al., Arch Intern Med 169:463–473, 2009, http://dx.doi.org/10.1001/archinternmed.2008.603, and H. Wisplinghoff et al., Clin Infect Dis 39:309–317, 2004, http://dx.doi.org/10.1086/421946). Even with current medical advances, S. aureus bloodstream infections and infective endocarditis carry mortality rates of 20 to 66% (S. Y. Tong et al., Clin Microbiol Rev 28:603–661, 2015, http://dx.doi.org/10.1128/CMR.00134-14). S. aureus lineages associated with human disease worldwide include clonal complex 5 (CC5)/USA100, CC30/USA200, CC8/USA300, CC1/USA400, and CC45/USA600. The CC5/USA100, CC30/USA200, and CC45/USA600 lineages cause invasive disease yet remain poorly characterized. USA300 and cytotoxins are central to most S. aureus virulence studies, and yet, we find evidence that clonal groups are quite heterogeneous in parameters canonically used to measure virulence, including cytotoxicity, biofilm formation, and blood survival, and that the superantigen profile is an important parameter to consider when defining the virulence of S. aureus strains. Staphylococcus aureus diseases affect ~500,000 individuals per year in the United States. Worldwide, the USA100, USA200, USA400, and USA600 lineages cause many of the life-threatening S. aureus infections, such as bacteremia, infective endocarditis, pneumonia, toxic shock syndrome, and surgical site infections. However, the virulence mechanisms associated with these clonal lineages, in particular the USA100 and USA600 isolates, have been severely understudied. We investigated the virulence of these strains, in addition to strains in the USA200, USA300, and USA400 types, in well-established in vitro assays and in vivo in the rabbit model of infective endocarditis and sepsis. We show in the infective endocarditis and sepsis model that strains in the USA100 and USA600 lineages cause high lethality and are proficient in causing native valve infective endocarditis. Strains with high cytolytic activity or producing toxic shock syndrome toxin 1 (TSST-1) or staphylococcal enterotoxin C (SEC) caused lethal sepsis, even with low cytolytic activity. Strains in the USA100, USA200, USA400, and USA600 lineages consistently contained genes that encode for the enterotoxin gene cluster proteins, SEC, or TSST-1 and were proficient at causing infective endocarditis, while the USA300 strains lacked these toxins and were deficient in promoting vegetation growth. The USA100, USA200, and USA400 strains in our collection formed strong biofilms in vitro, whereas the USA200 and USA600 strains exhibited increased blood survival. Hence, infective endocarditis and lethal sepsis are multifactorial and not intrinsic to any one individual clonal group, further highlighting the importance of expanding our knowledge of S. aureus pathogenesis to clonal lineages causative of invasive disease. IMPORTANCES. aureus is the leading cause of infective endocarditis in the developed world, affecting ~40,000 individuals each year in the United States, and the second leading cause of bacteremia (D. R. Murdoch et al., Arch Intern Med 169:463–473, 2009, http://dx.doi.org/10.1001/archinternmed.2008.603, and H. Wisplinghoff et al., Clin Infect Dis 39:309–317, 2004, http://dx.doi.org/10.1086/421946). Even with current medical advances, S. aureus bloodstream infections and infective endocarditis carry mortality rates of 20 to 66% (S. Y. Tong et al., Clin Microbiol Rev 28:603–661, 2015, http://dx.doi.org/10.1128/CMR.00134-14). S. aureus lineages associated with human disease worldwide include clonal complex 5 (CC5)/USA100, CC30/USA200, CC8/USA300, CC1/USA400, and CC45/USA600. The CC5/USA100, CC30/USA200, and CC45/USA600 lineages cause invasive disease yet remain poorly characterized. USA300 and cytotoxins are central to most S. aureus virulence studies, and yet, we find evidence that clonal groups are quite heterogeneous in parameters canonically used to measure virulence, including cytotoxicity, biofilm formation, and blood survival, and that the superantigen profile is an important parameter to consider when defining the virulence of S. aureus strains.
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Ko YP, Flick MJ. Fibrinogen Is at the Interface of Host Defense and Pathogen Virulence in Staphylococcus aureus Infection. Semin Thromb Hemost 2016; 42:408-21. [PMID: 27056151 PMCID: PMC5514417 DOI: 10.1055/s-0036-1579635] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Fibrinogen not only plays a pivotal role in hemostasis but also serves key roles in antimicrobial host defense. As a rapidly assembled provisional matrix protein, fibrin(ogen) can function as an early line of host protection by limiting bacterial growth, suppressing dissemination of microbes to distant sites, and mediating host bacterial killing. Fibrinogen-mediated host antimicrobial activity occurs predominantly through two general mechanisms, namely, fibrin matrices functioning as a protective barrier and fibrin(ogen) directly or indirectly driving host protective immune function. The potential of fibrin to limit bacterial infection and disease has been countered by numerous bacterial species evolving and maintaining virulence factors that engage hemostatic system components within vertebrate hosts. Bacterial factors have been isolated that simply bind fibrinogen or fibrin, promote fibrin polymer formation, or promote fibrin dissolution. Staphylococcus aureus is an opportunistic gram-positive bacterium, the causative agent of a wide range of human infectious diseases, and a prime example of a pathogen exquisitely sensitive to host fibrinogen. Indeed, current data suggest fibrinogen serves as a context-dependent determinant of host defense or pathogen virulence in Staphylococcus infection whose ultimate contribution is dictated by the expression of S. aureus virulence factors, the path of infection, and the tissue microenvironment.
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Affiliation(s)
- Ya-Ping Ko
- Center for Infectious and Inflammatory Diseases, Institute for Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas
| | - Matthew J. Flick
- Division of Experimental Hematology and Cancer Biology, Cancer and Blood Diseases Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
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Ostrowsky B, Ruiz R, Brown S, Chung P, Koppelman E, van Deusen Lukas C, Guo Y, Jalon H, Sumer Z, Araujo C, Sirtalan I, Brown C, Riska P, Currie B. Lessons learned from implementing Clostridium difficile-focused antibiotic stewardship interventions. Infect Control Hosp Epidemiol 2016; 35 Suppl 3:S86-95. [PMID: 25222903 DOI: 10.1086/677828] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE To determine whether controlling the prescription of targeted antibiotics would translate to a measurable reduction in hospital-onset Clostridium difficile infection (CDI) rates. DESIGN A multicenter before-and-after intervention comparative study. SETTING/PARTICIPANTS Ten medical centers in the greater New York region. Intervention group comprised of 6 facilities with early antimicrobial stewardship programs (ASPs). The 4 facilities without ASPs made up the nonintervention group. INTERVENTIONS/METHODS Intervention facilities identified target antibiotics using case-control studies and implemented ASP-based strategies to control their use. Pre- and postintervention hospital-onset CDI rates and antibiotic consumption were compared for a 20-month period from June 2010 to January 2012. Antibiotic usage was compared using defined daily dose, days of therapy, and number of courses prescribed. Comparisons used bivariate and regression techniques. RESULTS Intervention facilities identified piperacillin/tazobactam, fluoroquinolones, or cefepime (odds ratio, 2.0-9.8 in CDI case patients compared with those without CDI) as intervention targets and selected several interventions (all included a component of audit and feedback). Varying degrees of success were observed in reducing antibiotic consumption over time. Total target antibiotic use significantly decreased (P < .05) when measured by days of therapy and number of courses but not by defined daily dose. Intravenous moxifloxacin and oral ciprofloxacin use showed significant reduction when measured by defined daily dose and days of therapy (P ≤ .01). Number of courses with all forms of these antibiotics was reduced (P < .005). Intervention hospitals reported fewer hospital-onset CDI cases (2.8 rate point difference) compared with nonintervention hospitals; however, we were unable to show statistically significant decreases in aggregate hospital-onset CDI either between intervention and nonintervention groups or within the intervention group over time. CONCLUSIONS Although decreases in target antibiotic consumption did not translate into reductions of hospital-onset CDI in this study, many valuable lessons (including implementation strategies and antibiotic consumption measures) were learned. The findings can inform potential policy decisions regarding incorporating control of CDI and ASP as healthcare quality measures.
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Strategies to Prevent Methicillin-ResistantStaphylococcus aureusTransmission and Infection in Acute Care Hospitals: 2014 Update. Infect Control Hosp Epidemiol 2016; 35 Suppl 2:S108-32. [DOI: 10.1017/s0899823x00193882] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Previously published guidelines are available that provide comprehensive recommendations for detecting and preventing healthcare-associated infections (HAIs). The intent of this document is to highlight practical recommendations in a concise format designed to assist acute care hospitals in implementing and prioritizing their methicillin-resistantStaphylococcus aureus(MRSA) prevention efforts. This document updates “Strategies to Prevent Transmission of Methicillin-ResistantStaphylococcus aureusin Acute Care Hospitals,” published in 2008. This expert guidance document is sponsored by the Society for Healthcare Epidemiology of America (SHEA) and is the product of a collaborative effort led by SHEA, the Infectious Diseases Society of America (IDSA), the American Hospital Association (AHA), the Association for Professionals in Infection Control and Epidemiology (APIC), and The Joint Commission, with major contributions from representatives of a number of organizations and societies with content expertise. The list of endorsing and supporting organizations is presented in the introduction to the 2014 updates.
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Heltshe SL, Saiman L, Popowitch EB, Miller MB, Kloster M, Thompson V, Ferkol TW, Hoover WC, Schechter MS, Muhlebach MS. Outcomes and Treatment of Chronic Methicillin-Resistant Staphylococcus aureus Differs by Staphylococcal Cassette Chromosome mec (SCCmec) Type in Children With Cystic Fibrosis. J Pediatric Infect Dis Soc 2015; 4:225-31. [PMID: 26336603 PMCID: PMC4554198 DOI: 10.1093/jpids/piu048] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 04/30/2014] [Indexed: 12/29/2022]
Abstract
BACKGROUND Methicillin-resistant Staphylococcus aureus (MRSA) infects ∼25% of patients with cystic fibrosis (CF) in the United States. We hypothesized that health-related outcomes differed between healthcare-associated (staphylococcal cassette chromosome mec [SCCmec] II) vs community-associated (SCCmec IV) MRSA strains in patients chronically infected with CF. METHODS At 7 CF centers, MRSA isolates were prospectively obtained from patients ≤18 years old with 2 or more positive MRSA cultures within 1 year. Isolates were classified by SCCmec type and Panton-Valentine-leukocidin (PVL) status at a core laboratory, and sites remained blinded to SCCmec type and PVL results. Prospective clinical data including antibiotic use, respiratory symptoms, and pulmonary exacerbations were obtained. RESULTS Among the 295 cohort participants with typeable MRSA isolates, 69.5% had SCCmec II PVL(-), 13.2% had SCCmec IV PVL(-), and 17.3% had SCCmec IV PVL(+) strains. During follow-up of 287 patients with prospective data after enrollment, the risk for pulmonary exacerbations was significantly higher among participants with SCCmec II than SCCmec IV strains (risk ratio [RR] = 1.13; P = .03) and higher in those with SCCmec IV PVL(-) than SCCmec IV PVL(+) strains (RR = 1.62; P < .0001). Neither decline in lung function nor changes in nutritional outcomes differed by SCCmec type or PVL status during the study period. CONCLUSIONS Participants harboring chronic SCCmec II MRSA received more antibiotics and may have more lung disease than those with SCCmec IV; PVL(+) isolates were not associated with more advanced disease.
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Affiliation(s)
- Sonya L. Heltshe
- Division of Pediatric Pulmonology, Department of Pediatrics, University of Washington School of Medicine, Seattle,Cystic Fibrosis Foundation Therapeutics Development Network Coordinating Center, Seattle Children's Research Institute, Washington
| | - Lisa Saiman
- Department of Pediatrics, Columbia University Medical Center, New York,Department of Infection Prevention & Control, New York-Presbyterian Hospital
| | - Elena B. Popowitch
- Department of Medicine and,Department of Microbiology and Immunology, University of North Carolina at Chapel Hill
| | - Melissa B. Miller
- Department of Medicine and,Department of Microbiology and Immunology, University of North Carolina at Chapel Hill
| | - Margaret Kloster
- Cystic Fibrosis Foundation Therapeutics Development Network Coordinating Center, Seattle Children's Research Institute, Washington
| | - Valeria Thompson
- Cystic Fibrosis Foundation Therapeutics Development Network Coordinating Center, Seattle Children's Research Institute, Washington
| | - Thomas W. Ferkol
- Department of Pediatrics,Department of Genetics, Washington University, St. Louis, Missouri
| | | | | | - Marianne S. Muhlebach
- Division of Pediatric Pulmonology, Department of Pediatrics, University of North Carolina at Chapel Hill
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Jensen KC, Hair BB, Wienclaw TM, Murdock MH, Hatch JB, Trent AT, White TD, Haskell KJ, Berges BK. Isolation and Host Range of Bacteriophage with Lytic Activity against Methicillin-Resistant Staphylococcus aureus and Potential Use as a Fomite Decontaminant. PLoS One 2015; 10:e0131714. [PMID: 26131892 PMCID: PMC4488860 DOI: 10.1371/journal.pone.0131714] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 06/04/2015] [Indexed: 11/29/2022] Open
Abstract
Staphylococcus aureus (SA) is a commensal bacterium and opportunistic pathogen commonly associated with humans and is capable of causing serious disease and death including sepsis, pneumonia, and meningitis. Methicillin-resistant SA (MRSA) isolates are typically resistant to many available antibiotics with the common exception of vancomycin. The presence of vancomycin resistance in some SA isolates combined with the current heavy use of vancomycin to treat MRSA infections indicates that MRSA may achieve broad resistance to vancomycin in the near future. New MRSA treatments are clearly needed. Bacteriophages (phages) are viruses that infect bacteria, commonly resulting in death of the host bacterial cell. Phage therapy entails the use of phage to treat or prevent bacterial infections. In this study, 12 phages were isolated that can replicate in human SA and/or MRSA isolates as a potential way to control these infections. 5 phage were discovered through mitomycin C induction of prophage and 7 others as extracellular viruses. Primary SA strains were also isolated from environmental sources to be used as tools for phage discovery and isolation as well as to examine the target cell host range of the phage isolates by spot testing. Primary isolates were tested for susceptibility to oxacillin in order to determine which were MRSA. Experiments were performed to assess the host range and killing potential of newly discovered phage, and significant reductions in bacterial load were detected. We explored the utility of some phage to decontaminate fomites (glass and cloth) and found a significant reduction in colony forming units of MRSA following phage treatment, including tests of a phage cocktail against a cocktail of MRSA isolates. Our findings suggest that phage treatment can be used as an effective tool to decontaminate human MRSA from both hard surfaces and fabrics.
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Affiliation(s)
- Kyle C. Jensen
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, 84602, United States of America
| | - Bryan B. Hair
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, 84602, United States of America
| | - Trevor M. Wienclaw
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, 84602, United States of America
| | - Mark H. Murdock
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, 84602, United States of America
| | - Jacob B. Hatch
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, 84602, United States of America
| | - Aaron T. Trent
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, 84602, United States of America
| | - Tyler D. White
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, 84602, United States of America
| | - Kyler J. Haskell
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, 84602, United States of America
| | - Bradford K. Berges
- Department of Microbiology and Molecular Biology, Brigham Young University, Provo, Utah, 84602, United States of America
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Calfee DP, Salgado CD, Milstone AM, Harris AD, Kuhar DT, Moody J, Aureden K, Huang SS, Maragakis LL, Yokoe DS. Strategies to prevent methicillin-resistant Staphylococcus aureus transmission and infection in acute care hospitals: 2014 update. Infect Control Hosp Epidemiol 2015; 35:772-96. [PMID: 24915205 DOI: 10.1086/676534] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Abstract
PURPOSE OF REVIEW This review examines the epidemiology, diagnosis, prognosis, treatment and prevention of community-acquired pneumonia (CAP) in adults. RECENT FINDINGS CAP is a significant cause of morbidity and mortality. Streptococcus pneumoniae is the most common CAP pathogen; however, microbial cause varies by geographic location and host factors. Identification of a microbial cause in CAP remains challenging - 30-65% of cases do not have a pathogen isolated. The use of molecular techniques in addition to culture, serology and urinary antigen testing has improved diagnostic yield. Scoring systems are useful for CAP prognostication and site of care decisions. Studies evaluating novel biomarkers including pro-B-type natriuretic peptide and procalcitonin suggest potential adjunctive roles in CAP prognosis. Guideline-based treatment for CAP has changed little in recent years. Effective and timely antimicrobial therapy is crucial in optimizing outcomes and should be based on local antimicrobial susceptibility patterns. Macrolides may have additional anti-inflammatory properties and a mortality benefit in severe CAP. Preventive strategies include immunization and modification of specific patient risk factors. SUMMARY CAP is common and causes considerable morbidity and mortality. A comprehensive approach including advanced diagnostic testing, effective and timely antimicrobial therapy and prevention is required to optimize CAP outcomes.
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Sherwood J, Park M, Robben P, Whitman T, Ellis MW. USA300 Methicillin-Resistant Staphylococcus aureus Emerging as a Cause of Bloodstream Infections at Military Medical Centers. Infect Control Hosp Epidemiol 2015; 34:393-9. [DOI: 10.1086/669866] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Background.USA300 methicillin-resistant Staphylococcus aureus (MRSA) is a common cause of skin and soft-tissue infection (SSTI) in military personnel. USA300 MRSA has emerged as an important cause of healthcare-associated bloodstream infection (BSI) in metropolitan centers.Objective.To determine the prevalence, risk factors, and patient outcomes associated with USA300 MRSA BSI in military tertiary medical centers.Design.Retrospective case-control study.Patients.Patients admitted during the period 2001–2009 with MRSA BSI.Setting.Walter Reed Army Medical Center (Washington, DC) and National Naval Medical Center (Bethesda, MD) tertiary medical centers with 500 inpatient beds combined, which provide care to active duty service members and military beneficiaries.Methods.After identifying patients with MRSA BSI, we collected epidemiological data from electronic medical records and characterized bacterial isolates using pulsed-field gel electrophoresis (PFGE).Results.A total of 245 MRSA BSI cases were identified, and 151 isolates were available for analysis. Epidemiological characteristics for the 151 patients with available isolates included the following: mean age, 61 years; male sex, 70%; white race, 62%; and combat-wounded service members, 11%. The crude in-hospital mortality rate was 17%. PFGE demonstrated that 30 (20%) of 151 MRSA BSI cases with isolates available for analysis were due to USA300, and 27 (87%) of these 30 cases were healthcare-associated infection. USA300 was associated with a significantly increasing proportion of MRSA BSI when examined over sequential time periods: 2 (4%) of 51 isolates during 2001–2003, 9 (19%) of 47 isolates during 2004–2006, and 19 (36%) of 53 isolates during 2007–2009 (P<.001).Conclusion.USA300 MRSA is emerging as a cause of healthcare-associated BSI in tertiary military medical centers.
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Park KH, Chong YP, Kim SH, Lee SO, Choi SH, Lee MS, Jeong JY, Woo JH, Kim YS. Community-associated MRSA strain ST72-SCCmecIV causing bloodstream infections: clinical outcomes and bacterial virulence factors. J Antimicrob Chemother 2014; 70:1185-92. [PMID: 25433004 DOI: 10.1093/jac/dku475] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
OBJECTIVES Community-associated MRSA (CA-MRSA) has emerged in the community and has recently been spreading in healthcare settings. The objectives of this study were to evaluate the clinical outcomes and bacterial virulence factors of the Korean CA-MRSA (ST72-SCCmecIV) strain, which causes bloodstream infections. METHODS All adult patients with MRSA bacteraemia were prospectively enrolled. Clinical outcomes, microbiological characteristics and 40 bacterial virulence factors were evaluated. RESULTS Of the 352 typed MRSA isolates, 342 isolates (97.2%) belonged to three Panton-Valentine leucocidin-negative strains: ST5-SCCmecII (70.2%), ST72-SCCmecIV (22.4%) and ST239-SCCmecIII (4.6%). The remaining 10 (2.8%) isolates from minor strains were excluded from the final analysis. After controlling for several confounding factors, ST72-SCCmecIV was associated with the lowest mortality (compared with ST5-SCCmecII, adjusted OR=0.26; 95% CI=0.13-0.54). However, MRSA isolates with vancomycin MICs of ≥ 1.5 mg/L were more common in ST72-SCCmecIV compared with ST5-SCCmecII (84.8% versus 66.7%; P=0.002). Reduced vancomycin susceptibility and vancomycin heteroresistance were not associated with mortality. Compared with ST5-SCCmecII isolates, ST72-SCCmecIV isolates were less likely to harbour multiple virulence genes. Of these genes, three staphylococcal superantigen genes were associated with mortality: sec (OR=2.31; P=0.002), sel (OR=2.55; P=0.003) and tst (OR=2.76; P<0.001). CONCLUSIONS After controlling for confounding factors, ST72-SCCmecIV was independently associated with lower mortality compared with ST5-SCCmecII, suggesting this CA-MRSA strain to be of lower virulence. The lack of virulence genes, including staphylococcal superantigen genes, may play a role in the lower virulence of this strain.
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Affiliation(s)
- Ki-Ho Park
- Division of Infectious Diseases, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University School of Medicine, Seoul, Republic of Korea
| | - Yong Pil Chong
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
| | - Sung-Han Kim
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Sang-Oh Lee
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Sang-Ho Choi
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Mi Suk Lee
- Division of Infectious Diseases, Department of Internal Medicine, Kyung Hee University Hospital, Kyung Hee University School of Medicine, Seoul, Republic of Korea
| | - Jin-Yong Jeong
- Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea Asan Institute for Life Sciences, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jun Hee Woo
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Yang Soo Kim
- Department of Infectious Diseases, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea Center for Antimicrobial Resistance and Microbial Genetics, University of Ulsan, Seoul, Republic of Korea
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Popovich KJ, Hayden MK. Delineating the Epidemiology-Host-Microbe Relationship for Methicillin-ResistantStaphylococcus aureusInfection. J Infect Dis 2014; 211:1857-9. [DOI: 10.1093/infdis/jiu555] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 10/01/2014] [Indexed: 01/03/2023] Open
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Predictors of clinical success among a national Veterans Affairs cohort with methicillin-resistant Staphylococcus aureus pneumonia. Clin Ther 2014; 36:552-9. [PMID: 24631473 DOI: 10.1016/j.clinthera.2014.02.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Revised: 01/07/2014] [Accepted: 02/13/2014] [Indexed: 11/21/2022]
Abstract
BACKGROUND The treatment of methicillin-resistant Staphylococcus aureus (MRSA) pneumonia is exceedingly complicated, which is concerning because of the high mortality rate associated with the infection. Identification of independent predictors of clinical success can optimize patient care by assisting clinicians in treatment decisions. OBJECTIVES Our goal was to identify independent predictors of clinical success in a national Veterans Affairs (VA) cohort of patients with MRSA pneumonia. METHODS A nested case-control study was conducted among a cohort of VA patients with MRSA pneumonia receiving linezolid or vancomycin between January 2002 and September 2010. Cases included those demonstrating clinical success, defined as discharge from the hospital or intensive care unit by day 14 after treatment initiation, in the absence of death, therapy change, or intubation by day 14. Control subjects represented nonsuccess, defined as therapy change, intubation, intensive care unit admission, readmission, or death between treatment initiation and day 14. The potential predictors assessed included treatment, patient demographic and admission characteristics, previous health care and medication exposures, comorbidities, and medical history. Odds ratios (ORs) and 95% CIs were calculated from logistic regression. RESULTS Our study included 2442 cases of clinical success and 1290 control subjects. Demographic characteristics varied between the clinical success and nonsuccess groups, including age, race, and region of facility. A current diagnosis of chronic respiratory disease (46% vs 42%) and diagnosis of pneumonia in the year before the MRSA pneumonia admission (37% vs 32%) were both more common in the clinical success group. Despite these significant differences, only 2 predictors of clinical success were identified in our study: previous complication of an implant or graft, including mechanical complications and infections, in the year before the MRSA pneumonia admission (adjusted OR, 1.55 [95% CI, 1.17-2.06]) and treatment with linezolid (adjusted OR, 1.53 [95% CI, 1.12-2.10]). Predictors of nonsuccess (adjusted OR [95% CI) included diagnosis of concomitant urinary tract infection (0.82 [0.70-0.96]), intravenous line (0.76 [0.66-0.89]), previous coagulopathy (0.74 [0.56-0.96]), previous amputation procedure (0.72 [0.53-0.98]), current coagulopathy diagnosis (0.71 [0.53-0.96]), dialysis (0.54 [0.38-0.76]), multiple inpatient procedures (0.53 [0.45-0.62]), inpatient surgery (0.48 [0.41-0.57]), and previous endocarditis (0.24 [0.07-0.81]). CONCLUSIONS MRSA pneumonia tends to affect patients with complex care, and identification of the predictors of clinical success is useful when considering different therapeutic approaches. In this national cohort of VA patients with MRSA pneumonia, treatment was the only modifiable variable predicting clinical success.
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Aoyagi T, Kaito C, Sekimizu K, Omae Y, Saito Y, Mao H, Inomata S, Hatta M, Endo S, Kanamori H, Gu Y, Tokuda K, Yano H, Kitagawa M, Kaku M. Impact of psm-mec in the mobile genetic element on the clinical characteristics and outcome of SCCmec-II methicillin-resistant Staphylococcus aureus bacteraemia in Japan. Clin Microbiol Infect 2014; 20:912-9. [PMID: 24476401 DOI: 10.1111/1469-0691.12575] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Revised: 01/20/2014] [Accepted: 01/27/2014] [Indexed: 11/28/2022]
Abstract
Over-expression of alpha-phenol-soluble modulins (PSMs) results in high virulence of community-associated methicillin-resistant Staphylococcus aureus (MRSA). The psm-mec gene, located in the mobile genetic element SCCmec-II, suppresses PSMαs production. Fifty-two patients with MRSA bacteraemia were enrolled. MRSA isolates were evaluated with regard to the psm-mec gene sequence, bacterial virulence, and the minimum inhibitory concentration (MIC) of vancomycin and teicoplanin. Fifty-one MRSA isolates were classified as SCCmec-II, and 10 had one point mutation in the psm-mec promoter. We compared clinical characteristics and outcomes between mutant MRSA and wild-type MRSA. Production of PSMα3 in mutant MRSA was significantly increased, but biofilm formation was suppressed. Wild-type MRSA caused more catheter-related bloodstream infections (30/41 vs. 3/10, p 0.0028), whereas mutant MRSA formed more deep abscesses (4/10 vs. 3/41, p 0.035). Bacteraemia caused by mutant MRSA was associated with reduced 30-day mortality (1/10 vs. 13/41, p 0.25), although this difference was not significant. The MIC90 of teicoplanin was higher for wild-type MRSA (1.5 mg/L vs. 1 mg/L), but the MIC of vancomycin was not different between the two groups. The 30-day mortality of MRSA with a high MIC of teicoplanin (≥1.5 mg/L) was higher than that of strains with a lower MIC (≤0.75 mg/L) (6/10 vs. 6/33, p 0.017). Mutation of the psm-mec promoter contributes to virulence of SCCmec-II MRSA, and the product of psm-mec may determine the clinical characteristics of bacteraemia caused by SCCmec-II MRSA, but it does not affect mortality.
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Affiliation(s)
- T Aoyagi
- Department of Infection Control and Laboratory Diagnostics, Internal Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
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Paul SK, Ghosh S, Kawaguchiya M, Urushibara N, Hossain MA, Ahmed S, Mahmud C, Jilani MSA, Haq JA, Ahmed AA, Kobayashi N. Detection and genetic characterization of PVL-positive ST8-MRSA-IVa and exfoliative toxin D-positive European CA-MRSA-Like ST1931 (CC80) MRSA-IVa strains in Bangladesh. Microb Drug Resist 2014; 20:325-36. [PMID: 24552553 DOI: 10.1089/mdr.2013.0153] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Severe skin lesions caused by Staphylococcus aureus infection are associated with production from bacterial cells of Panton-Valentine leukocidin (PVL), a typical virulence factor of community-acquired methicillin-resistant S. aureus (CA-MRSA), as well as other toxins represented by exfoliative toxins. Through a retrospective study of 26 S. aureus strains isolated from skin lesions of diabetic patients admitted to a hospital in Bangladesh, 2 PVL-gene-positive MRSA-IVa strains and 8 PVL-negative, exfoliative toxin D (ETD) gene (etd)-positive MRSA-IVa strains were isolated. A PVL-positive MRSA-IVa strain had a type I arginine catabolic mobile element (ACME), belonged to ST8/agr-type I/spa-type t121 (a variant of t008), and harbored blaZ, tet(K), msrA, and aph(3')-IIIa, which are mostly typical characteristics found in USA300, a predominant CA-MRSA clone in the United States. Another PVL-positive MRSA strain, belonging to ST1929 (CC88)/agr-type III/spa-type t3341, was negative for ACME, but possessed blaZ and tet(K). The etd-positive MRSA-IVa strains possessed the epidermal cell differentiation inhibitor B (EDIN-B)-encoding gene (edinB) and belonged to ST1931 (CC80)/agr-type III/spa-type t11023 (a variant of t044), which was genetic trait similar to that of the European CA-MRSA ST80 clone. However, unlike the European ST80 strains, the etd-positive MRSA strains detected in the present study harbored seb, sek, and seq, while they were negative for tet(K), aph(3')-IIIa, and fusB, showing susceptibility to fusidic acid. These findings suggested that etd-positive ST1931 MRSA strains belong to the same lineage as the European ST80 MRSA clone, evolving from a common ancestral clone via acquisition of a different pathogenicity island. This is the first report of a USA300-like MRSA-IV strain, PVL-positive ST1929 (CC88) MRSA-IV, and European ST80 CA-MRSA-like etd-positive ST1931 (CC80) MRSA-IV strains isolated in Bangladesh.
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Affiliation(s)
- Shyamal Kumar Paul
- 1 Department of Microbiology, Mymensingh Medical College , Mymensingh, Bangladesh
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Aliberti S, Kaye KS. The changing microbiologic epidemiology of community-acquired pneumonia. Postgrad Med 2014; 125:31-42. [PMID: 24200759 DOI: 10.3810/pgm.2013.11.2710] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Community-acquired pneumonia (CAP) is a common infectious disease in the United States and the incidence continues to grow as the aging population increases. Overall, in-hospital patient mortality rates have been reported to be as high as 18%. Management of patients with CAP has been challenged by the evolution of resistant pathogens (particularly Streptococcus pneumoniae and Staphylococcus aureus) that have reduced susceptibility to recommended standard antimicrobial agents. Streptococcus pneumoniae continues to be the most frequently identified pathogen in CAP and recently, S. aureus has been found to be the second most often identified pathogen. Data from the SENTRY Antimicrobial Surveillance Program has shown declining susceptibility of pneumococci to penicillin, amoxicillin/clavulanate, and ceftriaxone from 1998 through 2011. In the Assessing Worldwide Resistance Evaluation (AWARE) surveillance program, > 50% of all S. aureus isolates from patient bloodstream infections, skin and skin structure infections, and pneumonia were methicillin-resistant. Stratifying risk factors to identify patients at risk for community-acquired multidrug-resistant pathogens should be considered when selecting therapy. Differences in microbiology and outcomes have been noted in patients presenting from the community with recent exposure to the health care system (eg, nursing home residents, patients with a recent hospital admission). These patients are at an increased risk of an infection caused by a multidrug-resistant pathogen. Understanding a patient's risk for drug-resistant pathogens will allow the physician to choose an appropriate empiric treatment regimen to optimize clinical outcomes.
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Affiliation(s)
- Stefano Aliberti
- Department of Health Science, University of Milan Bicocca, AO San Gerardo, Milan, Italy.
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Nair R, Ammann E, Rysavy M, Schweizer ML. Mortality among patients with methicillin-resistant Staphylococcus aureus USA300 versus non-USA300 invasive infections: a meta-analysis. Infect Control Hosp Epidemiol 2013; 35:31-41. [PMID: 24334796 DOI: 10.1086/674385] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
BACKGROUND Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has been found to be epidemiologically and microbiologically distinct from healthcare-associated MRSA. Most CA-MRSA infections are not invasive; however, fatal outcomes have been reported among healthy people with CA-MRSA invasive infections. Epidemiological studies have attributed a major burden of CA-MRSA infections in the United States to the predominant clone USA300. We investigated the association between USA300 invasive infections and mortality by conducting a systematic review and meta-analysis of studies that reported mortality rates associated with USA300 strains. METHODS We searched PubMed, bibliographies of other publications, and gray literature between January 2001 and December 2013. Observational studies of patients with an invasive MRSA infection were included. The exposure of interest was presence of USA300 invasive infection. Studies were included only if they provided MRSA PFGE types and if corresponding mortality data were the measured outcome. We pooled crude odds ratios (cORs) using a random-effects model. Woolf test of homogeneity and Q and I(2) statistics were assessed. RESULTS Of 574 articles identified by the search strategy, 8 met the inclusion criteria. Risk of mortality was significantly lower among patients with USA300 MRSA infections (pooled cOR, 0.63 [95% confidence interval (CI)], 0.49-0.81). There was a moderate degree of heterogeneity among study results (P = .29; I(2) = 18%). Results were observed to be heterogeneous due to study design, quality of studies, and definition of mortality. CONCLUSIONS MRSA invasive infection with USA300 does not appear to be associated with higher mortality compared with infections due to non-USA300 strains. Nevertheless, larger well-designed studies are warranted to further evaluate this association.
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Affiliation(s)
- Rajeshwari Nair
- Department of Epidemiology, College of Public Health, University of Iowa, Iowa City, Iowa
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207-nm UV light - a promising tool for safe low-cost reduction of surgical site infections. I: in vitro studies. PLoS One 2013; 8:e76968. [PMID: 24146947 PMCID: PMC3797730 DOI: 10.1371/journal.pone.0076968] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 09/05/2013] [Indexed: 11/19/2022] Open
Abstract
Background 0.5% to 10% of clean surgeries result in surgical-site infections, and attempts to reduce this rate have had limited success. Germicidal UV lamps, with a broad wavelength spectrum from 200 to 400 nm are an effective bactericidal option against drug-resistant and drug-sensitive bacteria, but represent a health hazard to patient and staff. By contrast, because of its limited penetration, ∼200 nm far-UVC light is predicted to be effective in killing bacteria, but without the human health hazards to skin and eyes associated with conventional germicidal UV exposure. Aims The aim of this work was to test the biophysically-based hypothesis that ∼200 nm UV light is significantly cytotoxic to bacteria, but minimally cytotoxic or mutagenic to human cells either isolated or within tissues. Methods A Kr-Br excimer lamp was used, which produces 207-nm UV light, with a filter to remove higher-wavelength components. Comparisons were made with results from a conventional broad spectrum 254-nm UV germicidal lamp. First, cell inactivation vs. UV fluence data were generated for methicillin-resistant S. aureus (MRSA) bacteria and also for normal human fibroblasts. Second, yields of the main UV-associated pre-mutagenic DNA lesions (cyclobutane pyrimidine dimers and 6-4 photoproducts) were measured, for both UV radiations incident on 3-D human skin tissue. Results We found that 207-nm UV light kills MRSA efficiently but, unlike conventional germicidal UV lamps, produces little cell killing in human cells. In a 3-D human skin model, 207-nm UV light produced almost no pre-mutagenic UV-associated DNA lesions, in contrast to significant yields induced by a conventional germicidal UV lamp. Conclusions As predicted based on biophysical considerations, 207-nm light kills bacteria efficiently but does not appear to be significantly cytotoxic or mutagenic to human cells. Used appropriately, 207-nm light may have the potential for safely and inexpensively reducing surgical-site infection rates, including those of drug-resistant origin.
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Immergluck LC, Satola SW, Jain S, McCracken C, Watson JR, Chan T, Leong T, Gottlieb E, Jerris RC. Methicillin-resistant Staphylococcus aureus colonization among pediatric health care workers from different outpatient settings. Am J Infect Control 2013; 41:841-3. [PMID: 23433983 DOI: 10.1016/j.ajic.2012.11.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Revised: 11/14/2012] [Accepted: 11/15/2012] [Indexed: 11/26/2022]
Abstract
Staphylococcus aureus colonization rates in pediatric health care workers from different types of outpatient settings were determined from December 2008 through May 2010. Colonization rates for Staphylococcus aureus and, specifically, methicillin-resistant Staphylococcus aureus (MRSA) rates were similar to the rates that have been reported for the general population. The predominant MRSA pulsed-field gel electrophoresis type associated with colonization in these health care workers is not MRSA USA300.
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Kawaguchiya M, Urushibara N, Ghosh S, Kuwahara O, Morimoto S, Ito M, Kudo K, Kobayashi N. Genetic diversity of emerging Panton-Valentine leukocidine/arginine catabolic mobile element (ACME)-positive ST8 SCCmec-IVa meticillin-resistant Staphylococcus aureus (MRSA) strains and ACME-positive CC5 (ST5/ST764) MRSA strains in Northern Japan. J Med Microbiol 2013; 62:1852-1863. [PMID: 23946478 DOI: 10.1099/jmm.0.062125-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Panton-Valentine leukocidine (PVL) is a distinctive virulence factor of community-associated meticillin-resistant Staphylococcus aureus (CA-MRSA), and arginine catabolic mobile element (ACME) is a staphylococcal genomic island that enhances fitness and the ability of bacterial cells to colonize on skin and mucous membranes. ACME is characteristically found in USA300, which is a predominant CA-MRSA clone [sequence type (ST) 8] in the USA and is spreading globally, and has also been detected in non-ST8 MRSA at low frequency. In Japan, spread of MRSA with PVL and/or ACME and their genetic traits have not yet been well characterized. In the present study, the prevalence and genetic diversity of PVL(+)/ACME(+) MRSA were investigated for 422 MRSA clinical isolates collected from outpatients in northern Japan over a period of 1 year. All the isolates were genotyped for the staphylococcal cassette chromosome mec (SCCmec) and coagulase genes (coa), and screened for PVL and ACME genes. The PVL(+)/ACME(+) isolates were studied further by genetic analysis, including single-nucleotide polymorphism (SNP) analysis based on PVL genes (lukS-PV-lukF-PV), ACME (arc and opp3 clusters) and the sarU promoter region. Among all the isolates examined, PVL genes and ACME were detected in eight (SCCmec-II, n = 1; SCCmec-IV, n = 6; SCCmec-V, n = 1) and 20 (SCCmec-II, n = 14; SCCmec-IV, n = 5; SCCmec-V, n = 1) isolates, respectively. Five isolates were found to have both PVL genes and ACME (type I), and were classified into ST8/spa-t008/agr-I/coa-IIIa, which is the same genetic traits as USA300. Fifteen PVL(-)/ACME(+) isolates had type ΔII-ACME, belonging to either ST5 or ST764 [clonal complex (CC) 5], and spa-t001, -t002 or -t3557. All the ST8 PVL(+)/ACME-I(+) MRSA had identical sequences of PVL genes (haplotype R) and ACME arc/opp3 clusters as those of USA300. In contrast, in the CC5 PVL(-)/ACME-ΔII(+) MRSA, SNPs in the arc cluster were detected in 11 sites (four haplotypes), with some different profiles of virulence/resistance factors. These results indicated single clonality of ST8 PVL(+)/ACME-I(+) MRSA and heterogeneity of CC5 PVL(-)/ACME-ΔII(+) MRSA, and suggest their potential spread in northern Japan.
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Affiliation(s)
- Mitsuyo Kawaguchiya
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo 060-8556, Japan
| | - Noriko Urushibara
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo 060-8556, Japan
| | - Souvik Ghosh
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo 060-8556, Japan
| | - Osamu Kuwahara
- Sapporo Clinical Laboratory Inc., Sapporo 060-0005, Japan
| | | | - Masahiko Ito
- Sapporo Clinical Laboratory Inc., Sapporo 060-0005, Japan
| | - Kenji Kudo
- Sapporo Clinical Laboratory Inc., Sapporo 060-0005, Japan
| | - Nobumichi Kobayashi
- Department of Hygiene, Sapporo Medical University School of Medicine, Sapporo 060-8556, Japan
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Schmid H, Romanos A, Schiffl H, Lederer SR. Persistent nasal methicillin-resistant staphylococcus aureus carriage in hemodialysis outpatients: a predictor of worse outcome. BMC Nephrol 2013; 14:93. [PMID: 23617360 PMCID: PMC3651301 DOI: 10.1186/1471-2369-14-93] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 04/17/2013] [Indexed: 11/11/2022] Open
Abstract
Background Nasal colonization with methicillin-resistant Staphylococcus aureus (MRSA) is a well defined risk factor for subsequent bacteremia and death in various groups of patients, but its impact on outcome in patients receiving long-term hemodialysis (HD) is under debate. Methods This prospective interventional cohort study (performed 2004 to 2010) enrolled 289 HD outpatients of an urban dialysis-unit. Nasal swab cultures for MRSA were performed in all patients upon first admission, at transfer from another dialysis facility or readmission after hospitalisation. Nasal MRSA carriers were treated in a separate ward and received mupirocin nasal ointment. Concomitant extra-nasal MRSA colonization was treated with 0.2% chlorhexidine mouth rinse (throat) or octenidine dihydrochloride containing antiseptic soaps and 2% chlorhexidine body washes (skin). Clinical data and outcome of carriers and noncarriers were systematically analyzed. Results The screening approach identified 34 nasal MRSA carriers (11.7%). Extra-nasal MRSA colonization was observed in 11/34 (32%) nasal MRSA carriers. History of malignancy and an increased Charlson Comorbidity Index were significant predictors for nasal MRSA carriers, whereas traditional risk factors for MRSA colonization or markers of inflammation or malnutrition were not able to discriminate. Kaplan-Meier analysis demonstrated significant survival differences between MRSA carriers and noncarriers. Mupirocin ointment persistently eliminated nasal MRSA colonization in 26/34 (73.5%) patients. Persistent nasal MRSA carriers with failure of this eradication approach had an extremely poor prognosis with an all-cause mortality rate >85%. Conclusions Nasal MRSA carriage with failure of mupirocin decolonization was associated with increased mortality despite a lack of overt clinical signs of infection. Further studies are needed to demonstrate whether nasal MRSA colonization represents a novel predictor of worse outcome or just another surrogate marker of the burden of comorbid diseases leading to fatal outcome in HD patients.
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Affiliation(s)
- Holger Schmid
- KFH Nierenzentrum Muenchen-Laim, Elsenheimerstr 36, 80687 Munich, Germany.
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Murphy CR, Hudson LO, Spratt BG, Elkins K, Terpstra L, Gombosev A, Nguyen C, Hannah P, Alexander R, Enright MC, Huang SS. Predictors of hospitals with endemic community-associated methicillin-resistant Staphylococcus aureus. Infect Control Hosp Epidemiol 2013; 34:581-7. [PMID: 23651888 DOI: 10.1086/670631] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE We sought to identify hospital characteristics associated with community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) carriage among inpatients. DESIGN Prospective cohort study. SETTING Orange County, California. PARTICIPANTS Thirty hospitals in a single county. METHODS We collected clinical MRSA isolates from inpatients in 30 of 31 hospitals in Orange County, California, from October 2008 through April 2010. We characterized isolates by spa typing to identify CA-MRSA strains. Using California's mandatory hospitalization data set, we identified hospital-level predictors of CA-MRSA isolation. RESULTS CA-MRSA strains represented 1,033 (46%) of 2,246 of MRSA isolates. By hospital, the median percentage of CA-MRSA isolates was 46% (range, 14%-81%). In multivariate models, CA-MRSA isolation was associated with smaller hospitals (odds ratio [OR], 0.97, or 3% decreased odds of CA-MRSA isolation per 1,000 annual admissions; P < .001, hospitals with more Medicaid-insured patients (OR, 1.2; P = .002), and hospitals with more patients with low comorbidity scores (OR, 1.3; P < .001). Results were similar when restricted to isolates from patients with hospital-onset infection. CONCLUSIONS Among 30 hospitals, CA-MRSA comprised nearly half of MRSA isolates. There was substantial variability in CA-MRSA penetration across hospitals, with more CA-MRSA in smaller hospitals with healthier but socially disadvantaged patient populations. Additional research is needed to determine whether infection control strategies can be successful in targeting CA-MRSA influx.
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Affiliation(s)
- Courtney R Murphy
- School of Social Ecology and Division of Infectious Diseases, University of California Irvine School of Medicine, Irvine, California.
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Post-discharge mortality in patients hospitalized with MRSA infection and/or colonization. Epidemiol Infect 2012; 141:1187-98. [PMID: 22971269 DOI: 10.1017/s0950268812001963] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) infection is known to increase in-hospital mortality, but little is known about its association with long-term health. Two hundred and thirty-seven deaths occurred among 707 patients with MRSA infection at the time of hospitalization and/or nasal colonization followed for almost 4 years after discharge from the Atlanta Veterans Affairs Medical Center, USA. The crude mortality rate in patients with an infection and colonization (23·57/100 person-years) was significantly higher than the rate in patients with only colonization (15·67/100 person-years, P = 0·037). MRSA infection, hospitalization within past 6 months, and histories of cancer or haemodialysis were independent risk factors. Adjusted mortality rates in patients with infection were almost twice as high compared to patients who were only colonized: patients infected and colonized [hazard ratio (HR) 1·93, 95% confidence interval (CI) 1·31-2·84]; patients infected but not colonized (HR 1·96, 95% CI 1·22-3·17). Surviving MRSA infection adversely affects long-term mortality, underscoring the importance of infection control in healthcare settings.
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Chen SY, Liao CH, Wang JL, Chiang WC, Lai MS, Chie WC, Chen WJ, Chang SC, Hsueh PR. Methicillin-resistant Staphylococcus aureus (MRSA) staphylococcal cassette chromosome mec genotype effects outcomes of patients with healthcare-associated MRSA bacteremia independently of vancomycin minimum inhibitory concentration. Clin Infect Dis 2012; 55:1329-37. [PMID: 22911641 DOI: 10.1093/cid/cis717] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Recent evidence has shown that community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is less virulent than traditional hospital-associated MRSA. We explored whether the antimicrobial susceptibilities of the different strains account for their disparity in clinical virulence. METHODS This 10-year retrospective cohort study enrolled 291 patients with community-onset, healthcare-associated MRSA bacteremia. The vancomycin minimum inhibitory concentration (MIC) and staphylococcal cassette chromosome mec (SCCmec) type were determined for all isolates. CA-MRSA was defined as an isolate possessing the SCCmec type IV or V genes, and hospital-associated MRSA (HA-MRSA) was defined as an isolate possessing SCCmec type I, II, or III genes. Low and high vancomycin MICs were defined as MICs of ≤1 and ≥2 μg/mL, respectively. Patients with bacteremia due to CA-MRSA with a low vancomycin MIC (n = 111), due to HA-MRSA with a low vancomycin MIC (n = 127), or due to HA-MRSA with a high vancomycin MIC (n = 47) entered the outcome analysis. The outcomes of the 2 HA-MRSA bacteremia groups were compared to those of the CA-MRSA bacteremia group. RESULTS Treatment failure was observed in 35 (31.5%), 59 (46.5%), and 27 (57.4%) of patients with low-vancomycin-MIC CA-MRSA, low-vancomycin-MIC HA-MRSA, and high-vancomycin-MIC HA-MRSA bacteremia, respectively. After adjustment for potential confounding factors, the risk of treatment failure was significantly higher among patients with low-vancomycin-MIC HA-MRSA (adjusted odds ratio [aOR], 1.853; 95% confidence interval [CI], 1.006-3.413) and high-vancomycin-MIC HA-MRSA (aOR, 2.393; 95% CI, 1.079-5.309), compared with patients with low-vancomycin-MIC CA-MRSA. CONCLUSIONS The higher risk for treatment failure among patients with traditional hospital-associated MRSA infections, compared with patients with CA-MRSA infections, is independent of the vancomycin MIC, suggesting a potential intrinsic strain-specific virulence effect.
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Affiliation(s)
- Shey-Ying Chen
- Department of Emergency Medicine, National Taiwan University Hospital, Taipei, Taiwan
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A mutation in the PP2C phosphatase gene in a Staphylococcus aureus USA300 clinical isolate with reduced susceptibility to vancomycin and daptomycin. Antimicrob Agents Chemother 2012; 56:5212-23. [PMID: 22850507 DOI: 10.1128/aac.05770-11] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) strains with reduced susceptibility to vancomycin (MIC of 4 to 8 μg/ml) are referred to as vancomycin-intermediate S. aureus (VISA). In this study, we characterized two isogenic USA300 S. aureus isolates collected sequentially from a single patient with endocarditis where the S. aureus isolate changed from being susceptible to vancomycin (VSSA) (1 μg/ml) to VISA (8 μg/ml). In addition, the VISA isolate lost beta-lactamase activity and showed increased resistance to daptomycin and linezolid. The two strains did not differ in growth rate, but the VISA isolate had a thickened cell wall and was less autolytic. Transcriptome sequencing (RNA-seq) analysis comparing the two isolates grown to late exponential phase showed significant differences in transcription of cell surface protein genes (spa, SBI [second immunoglobulin-binding protein of S. aureus], and fibrinogen-binding proteins), regulatory genes (agrBCA, RNAIII, sarT, and saeRS), and others. Using whole-genome shotgun resequencing, we identified 6 insertion/deletion mutations between the VSSA and VISA isolates. A protein phosphatase 2C (PP2C) family phosphatase had a 6-bp (nonframeshift) insertion mutation in a highly conserved metal binding domain. Complementation of the clinical VISA isolate with a wild-type copy of the PP2C gene reduced the vancomycin and daptomycin MICs and increased autolytic activity, suggesting that this gene contributed to the reduced vancomycin susceptibility phenotype acquired in vivo. Creation of de novo mutants from the VSSA strain resulted in different mutations, demonstrating that reduced susceptibility to vancomycin in USA300 strains can occur via multiple routes, highlighting the complex nature of the VISA phenotype.
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