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Lynch JP, Zhanel GG. Escalation of antimicrobial resistance among MRSA part 1: focus on global spread. Expert Rev Anti Infect Ther 2023; 21:99-113. [PMID: 36470275 DOI: 10.1080/14787210.2023.2154653] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
INTRODUCTION Staphylococcus aureus produce numerous virulence factors that influence tissue invasion, cytotoxicity, membrane damage, and intracellular persistence allowing them to be very common human pathogens. S. aureus isolates exhibit considerable diversity though specific genotypes have been associated with antimicrobial resistance (AMR) and toxin gene profiles. MRSA is an important pathogen causing both community-acquired (CA) and healthcare-acquired (HCA) infections. Importantly, over the past several decades, both HCA-MRSA and CA-MRSA have spread all over the globe. Even more concerning is that CA-MRSA clones have disseminated into hospitals and HCA-MRSA have entered the community. Factors that enhance spread of MRSA include: poor antimicrobial stewardship and inadequate infection control. The emergence and spread of multidrug resistant (MDR) MRSA has limited therapeutic options. AREAS COVERED The authors discuss the escalation of MRSA, both HCA-MRSA and CA-MRSA across the globe. A literature search of MRSA was performed via PubMed (up to September 2022), using the key words: antimicrobial resistance; β-lactams; community-associated MRSA; epidemiology; infection; multidrug resistance; Staphylococcus aureus. EXPERT OPINION Over the past several decades, MRSA has spread all over the globe. We encourage the judicious use of antimicrobials in accordance with antimicrobial stewardship programs along with infection control measures to minimize the spread of MRSA.
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Affiliation(s)
- Joseph P Lynch
- Division of Pulmonary, Critical Care Medicine, Allergy, and Clinical Immunology, Department of Internal Medicine, The David Geffen School of Medicine at Ucla, Los Angeles, CA, USA
| | - George G Zhanel
- Professor-Department of Medical Microbiology and Infectious Diseases, Department of Medical Microbiology/Infectious Diseases, Max Rady College of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
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Souza CLSE, Barbosa CD, Coelho HILN, Santos Júnior MN, Barbosa EN, Queiroz ÉC, Teles MF, Dos Santos DC, Bittencourt RS, Soares TDJ, Oliveira MV, Timenetsky J, Campos GB, Marques LM. Effects of 17β-Estradiol on Monocyte/Macrophage Response to Staphylococcus aureus: An In Vitro Study. Front Cell Infect Microbiol 2021; 11:701391. [PMID: 34336722 PMCID: PMC8317603 DOI: 10.3389/fcimb.2021.701391] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/29/2021] [Indexed: 01/23/2023] Open
Abstract
To describe how 17β-estradiol (E2) influence in the monocyte/macrophage response induced by S. aureus in in vitro models of murine peritoneal macrophages (MPMs) and human peripheral blood monocytes (HPBM). MPMs (2 x 105/ml) were isolated from sham (n=3) and ovariectomized (OVX) females (n = 3) and males (n = 3) after induction by thioglycolate. The MPMs obtained from OVX females and males were treated for 24 hours with 17β-estradiol (E2) (10-7 M), and after that, inoculation with S. aureus was carried out for 6 hours. The macrophages were collected and destined to evaluate the relative gene expression of TNF-α, IL-1β, IL-6, IL-8 and TLR2. For the in vitro model of HPBMs, six men and six women of childbearing age were selected and HPBMs were isolated from samples of the volunteers’ peripheral blood. In women, blood was collected both during menstruation and in the periovulatory period. HPBMs were inoculated with S. aureus for 6 hours and the supernatant was collected for analysis of cytokines by Luminex and the HPBMs were removed for analysis of 84 genes involved in the host’s response to bacterial infections by RT-PCR array. Previous treatment with E2 decreased the gene expression and production of proinflammatory cytokines, such as TNF-α, IL-1β and IL-6 and decreased the expression of TLR2 tanto em MPMs quanto em HPBMs. The analysis of gene expression shows that E2 inhibited the NFκB pathway. It is suggested that 17β-estradiol acts as an immunoprotective in the monocyte/macrophage response induced by S. aureus.
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Affiliation(s)
- Clarissa Leal Silva E Souza
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil.,Santo Agostinho School of Health (FASA), Santo Agostinho Colleges, Afya Educational, Vitória da Conquista, Brazil
| | - Camila Dutra Barbosa
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil
| | - Hanna I L N Coelho
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil
| | - Manoel N Santos Júnior
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil.,University of Santa Cruz (UESC), Ilhéus, Brazil
| | - Elaine Novaes Barbosa
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil
| | - Éllunny Chaves Queiroz
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil
| | - Mauro Fernandes Teles
- Santo Agostinho School of Health (FASA), Santo Agostinho Colleges, Afya Educational, Vitória da Conquista, Brazil
| | - Déborah Cruz Dos Santos
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil
| | - Rafaela Souza Bittencourt
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil
| | - Telma de Jesus Soares
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil
| | | | - Jorge Timenetsky
- Department of Microbiology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
| | - Guilherme Barreto Campos
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil
| | - Lucas Miranda Marques
- Multidisciplinary Institute of Health, Federal University of Bahia (UFBA), Vitória da Conquista, Brazil.,University of Santa Cruz (UESC), Ilhéus, Brazil.,Department of Microbiology, Institute of Biomedical Science, University of São Paulo, São Paulo, Brazil
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The History of Methicillin-Resistant Staphylococcus aureus in Brazil. ACTA ACUST UNITED AC 2020; 2020:1721936. [PMID: 33082892 PMCID: PMC7563066 DOI: 10.1155/2020/1721936] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 07/21/2020] [Accepted: 09/24/2020] [Indexed: 12/20/2022]
Abstract
Since the emergence of MRSA in the 1960s, a gradual increase in infections by resistant bacteria has been observed. Clinical manifestations may vary from brand to critical condition due to host risk factors, as well as pathogen virulence and resistance. The high adaptability and pathogenic profile of MRSA clones contributed to its spread in hospital and community settings. In Brazil, the first MRSA isolates were reported in the late 1980s, and since then different genetic profiles, such as the Brazilian epidemic clone (BEC) and other clones considered a pandemic, became endemic in the Brazilian population. Additionally, Brazil's MRSA clones were shown to be able to transfer genes involved in multidrug resistance and enhanced pathogenic properties. These events contributed to the rise of highly resistant and pathogenic MRSA. In this review, we present the main events which compose the history of MRSA in Brazil, including numbers and locations of isolation, as well as types of staphylococcal cassette chromosome mec (SCCmec) found in the Brazilian territory.
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Niek WK, Teh CSJ, Idris N, Sit PS, Lee YQ, Thong KL, Sri La Sri Ponnampalavanar S. Methicillin-resistant Staphylococcus aureus bacteraemia, 2003-2015: Comparative evaluation of changing trends in molecular epidemiology and clinical outcomes of infections. INFECTION GENETICS AND EVOLUTION 2020; 85:104567. [PMID: 32980576 DOI: 10.1016/j.meegid.2020.104567] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Revised: 08/24/2020] [Accepted: 09/21/2020] [Indexed: 11/25/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a prominent pathogen causing invasive infections such as bacteraemia. The continued excessive use of antibiotics to treat MRSA infections has resulted in the evolution of antimicrobial resistant of S. aureus. This study aims to perform a comparative evaluation of changing trends in molecular epidemiology of MRSA and clinical characteristics of patients. This study shows that ST22-MRSA-IV has gradually replaced ST239-MRSA-III as the predominant MRSA clone in the tertiary teaching hospital studied. Independent predictors of mortality among patients included devices in situ at the time of infection, pre-exposure to macrolides, catheter-related bloodstream infection and mono-microbial infection. Hence, our study affirmed community-associated MRSA, which was previously identified from individuals without any exposure to healthcare settings, has now emerged in healthcare settings, causing healthcare-associated MRSA infections.
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Affiliation(s)
- Wen Kiong Niek
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Cindy Shuan Ju Teh
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia..
| | - Nuryana Idris
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Pik San Sit
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Yee Qing Lee
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, 50603 Kuala Lumpur, Malaysia
| | - Kwai Lin Thong
- NANOCAT Research Centre, University of Malaya, 50603, Kuala Lumpur, Malaysia
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Joo EJ, Park DA, Kang CI, Chung DR, Song JH, Lee SM, Peck KR. Reevaluation of the impact of methicillin-resistance on outcomes in patients with Staphylococcus aureus bacteremia and endocarditis. Korean J Intern Med 2019; 34:1347-1362. [PMID: 29347812 PMCID: PMC6823568 DOI: 10.3904/kjim.2017.098] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 07/08/2017] [Indexed: 02/04/2023] Open
Abstract
BACKGROUND/AIMS Methicillin-resistant Staphylococcus aureus (MRSA) is highly prevalent in hospitals, and has recently emerged in the community. The impact of methicillin-resistance on mortality and medical costs for patients with S. aureus bacteremia (SAB) requires reevaluation. METHODS We searched studies with SAB or endocarditis using electronic databases including Ovid-Medline, Embase-Medline, and Cochrane Library, as well as five local databases for published studies during the period January 2000 to September 2011. RESULTS A total of 2,841 studies were identified, 62 of which involved 17,563 adult subjects and were selected as eligible. A significant increase in overall mortality associated with MRSA, compared to that with methicillin-susceptible S. aureus (MSSA), was evidenced by an odds ratio (OR) of 1.95 (95% confidence interval [CI], 1.73 to 2.21; p < 0.01). In 13 endocarditis studies, MRSA increased the risk of mortality, with an OR of 2.65 (95% CI, 1.46 to 4.80). When three studies, which compared mortality rates between CA-MRSA and CA-MSSA, were combined, the risk of methicillin-resistance increased 3.23-fold compared to MSSA (95% CI, 1.25 to 8.34). The length of hospital stay in the MRSA group was 10 days longer than that in the MSSA group (95% CI, 3.36 to 16.70). Of six studies that reported medical costs, two were included in the analysis, which estimated medical costs to be $9,954.58 (95% CI, 8,951.99 to 10,957.17). CONCLUSION MRSA is still associated with increased mortality, longer hospital stays and medical costs, compared with MSSA in SAB in studies published since the year 2000.
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Affiliation(s)
- Eun-Jeong Joo
- Division of Infectious Diseases, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Dong Ah Park
- Office of Health Technology Evaluation, National Evidence-based Healthcare Collaboration Agency, Seoul, Korea
| | - Cheol-In Kang
- Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Doo Ryeon Chung
- Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jae-Hoon Song
- Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sang Moo Lee
- Office of Health Technology Evaluation, National Evidence-based Healthcare Collaboration Agency, Seoul, Korea
| | - Kyong Ran Peck
- Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- Correspondence to Kyong Ran Peck, M.D. Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 06351, Korea Tel: +82-2-3410-0329 Fax: +82-2-3410-0064 E-mail:
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Vázquez-Martínez ER, García-Gómez E, Camacho-Arroyo I, González-Pedrajo B. Sexual dimorphism in bacterial infections. Biol Sex Differ 2018; 9:27. [PMID: 29925409 PMCID: PMC6011518 DOI: 10.1186/s13293-018-0187-5] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 06/08/2018] [Indexed: 12/21/2022] Open
Abstract
Background Sex differences are important epidemiological factors that impact in the frequency and severity of infectious diseases. A clear sexual dimorphism in bacterial infections has been reported in both humans and animal models. Nevertheless, the molecular mechanisms involved in this gender bias are just starting to be elucidated. In the present article, we aim to review the available data in the literature that report bacterial infections presenting a clear sexual dimorphism, without considering behavioral and social factors. Main body The sexual dimorphism in bacterial infections has been mainly attributed to the differential levels of sex hormones between males and females, as well as to genetic factors. In general, males are more susceptible to gastrointestinal and respiratory bacterial diseases and sepsis, while females are more susceptible to genitourinary tract bacterial infections. However, these incidences depend on the population evaluated, animal model and the bacterial species. Female protection against bacterial infections and the associated complications is assumed to be due to the pro-inflammatory effect of estradiol, while male susceptibility to those infections is associated with the testosterone-mediated immune suppression, probably via their specific receptors. Recent studies indicate that the protective effect of estradiol depends on the estrogen receptor subtype and the specific tissue compartment involved in the bacterial insult, suggesting that tissue-specific expression of particular sex steroid receptors contributes to the susceptibility to bacterial infections. Furthermore, this gender bias also depends on the effects of sex hormones on specific bacterial species. Finally, since a large number of genes related to immune functions are located on the X chromosome, X-linked mosaicism confers a highly polymorphic gene expression program that allows women to respond with a more expanded immune repertoire as compared with men. Conclusion Notwithstanding there is increasing evidence that confirms the sexual dimorphism in certain bacterial infections and the molecular mechanisms associated, further studies are required to clarify conflicting data and to determine the role of specific hormone receptors involved in the gender bias of bacterial infections, as well as their potential as therapeutic targets.
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Affiliation(s)
- Edgar Ricardo Vázquez-Martínez
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, Mexico
| | - Elizabeth García-Gómez
- Unidad de Investigación en Reproducción Humana, Consejo Nacional de Ciencia y Tecnología (CONACyT)-Instituto Nacional de Perinatología, Ciudad de México, Mexico
| | - Ignacio Camacho-Arroyo
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, Mexico
| | - Bertha González-Pedrajo
- Departamento de Genética Molecular, Instituto de Fisiología Celular, UNAM, Ciudad Universitaria, Av. Universidad 3000, Coyoacán, 04510, Ciudad de México, Mexico.
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Joo EJ, Chung DR, Kim SH, Baek JY, Lee NY, Cho SY, Ha YE, Kang CI, Peck KR, Song JH. Emergence of Community-Genotype Methicillin-Resistant Staphylococcus aureus in Korean Hospitals: Clinical Characteristics of Nosocomial Infections by Community-Genotype Strain. Infect Chemother 2017; 49:109-116. [PMID: 28608660 PMCID: PMC5500265 DOI: 10.3947/ic.2017.49.2.109] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 03/15/2017] [Indexed: 01/23/2023] Open
Abstract
Background As community-genotype methicillin-resistant Staphylococcus aureus (MRSA) strains spread into hospitals, the genotypes of the MRSA strains causing hospital-acquired (HA) infections have become more diverse. We describe clinical characteristics of nosocomial MRSA infections by a community-genotype of sequence type (ST) 72. Materials and Methods A case-control study was designed among patients with HA-MRSA infections. Forty patients with infections caused by ST72-MRSA SCCmec type IV were selected as cases. Cases were matched to the controls with 106 patients infected with ST5/ST239 MRSA, which are representative hospital genotypes in Korea. Results Patients infected with ST72 isolates were younger than those with ST5/ST239 isolates. Female gender predominated among ST72 MRSA group compared to ST5/ST239 MRSA group. Solid tumor was a more frequent underlying disease in MRSA infections by ST72 isolates, whereas underlying renal, lung, heart, and neurologic diseases were more frequently found in those by ST5/ST239 isolates. The most common type of infection was pneumonia in both ST72 and ST5/ST239 groups (45.0% vs. 51.9%), followed by skin and soft tissue infection (SSTI). Female gender and underlying solid tumor were identified to be independent predictors for MRSA infections by ST72 isolates. All-cause mortality rates (20.0% vs. 30.2%) were not different between the groups. Conclusion A community-genotype MRSA, ST72 isolate has emerged as a nosocomial pathogen presenting as hospital-acquired pneumonia and SSTI. Although differences in underlying disorders were found, the distribution of infection type and mortality rate did not differ between the groups.
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Affiliation(s)
- Eun Jeong Joo
- Division of Infectious Diseases, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Doo Ryeon Chung
- Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Asia Pacific Foundation for Infectious Diseases (APFID), Seoul, Korea.
| | - So Hyun Kim
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul, Korea
| | - Jin Yang Baek
- Asia Pacific Foundation for Infectious Diseases (APFID), Seoul, Korea
| | - Nam Yong Lee
- Department of Laboratory Medicine and Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Sun Young Cho
- Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Young Eun Ha
- Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Cheol In Kang
- Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Kyong Ran Peck
- Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jae Hoon Song
- Division of Infectious Diseases, Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.,Asia Pacific Foundation for Infectious Diseases (APFID), Seoul, Korea
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[Risk factors for methicillin-resistant Staphylococcus aureus bacteremia: A multicenter matched case-control study]. BIOMEDICA 2016; 36:612-619. [PMID: 27992988 DOI: 10.7705/biomedica.v36i4.3193] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Revised: 04/07/2016] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Methicillin-resistant Staphylococcus aureus is a frequent pathogen at critical care services. Its presence leads to increased hospital stays and mortality risk in patients with bacteremia. However, the etiology of this resistance marker has not been fully studied. OBJECTIVE To identify risk factors associated with the emergence of methicillin-resistant S. aureus bacteremia in critically ill patients treated at intensive care units in Bogotá, Colombia. MATERIALS AND METHODS We conducted a retrospective paired case-control study, nested in a cohort of patients diagnosed with S. aureus bacteremia and treated at intensive care units between 2006 and 2008 in Bogotá. Cases were patients with positive blood culture to methicillin resistance, matched in a 1:1 ratio with methicillin-sensitive controls isolated from the same institution and hospitalization year. We used conditional logistic regression to analyze the risk factors associated with the presence of resistance, with emphasis on prior antibiotic therapy. RESULTS We included 372 patients with S. aureus bacteremia. Factors such as the use of pre-hospital devices: vascular (OR=1.986, 95% CI 1.038 to 3.801) and urinary (OR=2.559, 95% CI: 1.170 to 5.596), along with the number of previously used antibiotics, were associated with the emergence of resistance. The number of antibiotics used previously was determined to have a gradient effect, particularly carbapenems. CONCLUSIONS The rational use of antibiotics and surveillance of exposure to surgical procedures or use of invasive devices are interventions that could diminish the emergence of methicillin-resistant S. aureus bacteremia causes.
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Andrade-Figueiredo M, Leal-Balbino TC. Clonal diversity and epidemiological characteristics of Staphylococcus aureus: high prevalence of oxacillin-susceptible mecA-positive Staphylococcus aureus (OS-MRSA) associated with clinical isolates in Brazil. BMC Microbiol 2016; 16:115. [PMID: 27325108 PMCID: PMC4915036 DOI: 10.1186/s12866-016-0733-4] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 06/08/2016] [Indexed: 11/15/2022] Open
Abstract
Background Staphylococcus aureus is the major cause of global and nosocomial infections with a significant impact in hospitals worldwide. Our objective was to investigate clinical and molecular characteristics of S. aureus isolates causing infections in patients admitted to hospitals from Recife city, Brazil, and investigate the prevalence of oxacillin-susceptible mecA-positive S. aureus (OS-MRSA) in the region, as well as genetically characterize the isolates and compare with epidemic clones. Results We characterized 89 isolates in total, 31 clinical methicillin-resistant S. aureus (MRSA) and 58 methicillin-sensitive (MSSA) isolates by PFGE, MLST, spa typing and SCCmec genotyping. Isolates belonging to international MRSA clones were present: Brazilian epidemic clone (BEC) (61 % of MRSA isolates), Paediatric (36 %), New York/Japan (3 %). Some MSSA isolates were related to MRSA clones: USA400-related (10 % of MSSA isolates), Berlin clone (2 %), Paediatric (14 %), New York/Japan (2 %) and Southwest Pacific clone (17 %). MLST revealed new sequence types (ST’s): ST2381, ST2382, and ST2383 and new spa types: 10548 and 10550. Among isolates phenotypically identified as MSSA by antimicrobial susceptibility assays, we verified 30 oxacillin-susceptible isolates, which exhibited the mecA gene, without mec complex amplification and were thus classified as OS-MRSA. We observed clonal spread of MRSA and MSSA, including OS-MRSA, within several areas of the main hospital investigated and closely related isolates between hospitals analyzed. Conclusions The results of this study suggest a possible spread of the strains in hospital environment that could be responsible for nosocomial infections. We documented the presence of several MRSA clones, as well as new MLST and spa types, that were responsible for severe infections in hospitalized patients. The finding of OS-MRSA isolates could have implications for therapy, because testing for mecA and PBP2a is not a routine procedure performed by clinical microbiology laboratories in Brazil and, as consequence, these isolates could be misclassified as MSSA. Our data alert to the necessity to develop more effective strategies for epidemiological control of S. aureus in order to avoid an increase of hospital infections provoked by this pathogen. We reinforce the use of genetic methods, in addition to phenotypic tests, for a precise identification of MRSA. Electronic supplementary material The online version of this article (doi:10.1186/s12866-016-0733-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Mariana Andrade-Figueiredo
- Department of Microbiology, Oswaldo Cruz Foundation, Aggeu Magalhães Research Center, CPqAM/Fiocruz, Av. Professor Moraes Rego, s/n - CamLpus da UFPE - Cidade Universitária, Recife, PE, 50.670-420, Brazil
| | - Tereza Cristina Leal-Balbino
- Department of Microbiology, Oswaldo Cruz Foundation, Aggeu Magalhães Research Center, CPqAM/Fiocruz, Av. Professor Moraes Rego, s/n - CamLpus da UFPE - Cidade Universitária, Recife, PE, 50.670-420, Brazil.
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Joo EJ, Choi JY, Chung DR, Song JH, Ko KS. Characteristics of the community-genotype sequence type 72 methicillin-resistant Staphylococcus aureus isolates that underlie their persistence in hospitals. J Microbiol 2016; 54:445-50. [PMID: 27225462 DOI: 10.1007/s12275-016-6157-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 05/16/2016] [Accepted: 05/18/2016] [Indexed: 10/21/2022]
Abstract
Panton-Valentine leukocidin-negative methicillin-resistant Staphylococcus aureus (MRSA) clone ST72, known as a major community-associated MRSA in Korea, has emerged as an important pathogen in hospitals. To understand bacterial properties that underlie transformation of this clone into a nosocomial pathogen, we compared characteristics of the community-genotype ST72 MRSA isolates with those of ST5 and ST239 MRSA, which have been predominant nosocomial MRSA clones in Korea. Several genes associated with adhesion and virulence were absent or rarely found in ST72 isolates. Many ST72 isolates (70.1%) belonged to agr group I, but the agr group of other ST72 isolates could not be determined. As indicated by d-hemolysin production, ST72 isolates expressed fully functional agr, whereas agr dysfunction was observed in ST5 and ST239 isolates. In the biofilm formation assay, no upregulation of biofilm-forming activity of ST72 MRSA was detected. However, ST72 isolates demonstrated persistence under hypotonic and desiccating conditions (survival rates 72.3% and 33.9%, respectively), which was similar to characteristics of ST5 or ST239 isolates. ST72- MRSA isolates showed low virulence, but properties of their functional agr system could facilitate their spread in hospitals. In conclusion, tolerance to stressful environments, e.g., hypotonic and dry conditions, may also contribute to survival of the community-associated MRSA clones in healthcare facilities.
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Affiliation(s)
- Eun-Jeong Joo
- Division of Infectious Diseases, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, 03181, Republic of Korea
| | - Ji-Young Choi
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea
| | - Doo Ryeon Chung
- Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea.,Asia-Pacific Foundation for Infectious Diseases (APFID), Seoul, 06351, Republic of Korea
| | - Jae-Hoon Song
- Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, 06351, Republic of Korea.,Asia-Pacific Foundation for Infectious Diseases (APFID), Seoul, 06351, Republic of Korea
| | - Kwan Soo Ko
- Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon, 16419, Republic of Korea. .,Asia-Pacific Foundation for Infectious Diseases (APFID), Seoul, 06351, Republic of Korea.
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Lawes T, López-Lozano JM, Nebot C, Macartney G, Subbarao-Sharma R, Dare CRJ, Edwards GFS, Gould IM. Turning the tide or riding the waves? Impacts of antibiotic stewardship and infection control on MRSA strain dynamics in a Scottish region over 16 years: non-linear time series analysis. BMJ Open 2015; 5:e006596. [PMID: 25814495 PMCID: PMC4386222 DOI: 10.1136/bmjopen-2014-006596] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
OBJECTIVES To explore temporal associations between planned antibiotic stewardship and infection control interventions and the molecular epidemiology of methicillin-resistant Staphylococcus aureus (MRSA). DESIGN Retrospective ecological study and time-series analysis integrating typing data from the Scottish MRSA reference laboratory. SETTING Regional hospital and primary care in a Scottish Health Board. PARTICIPANTS General adult (N=1,051,993) or intensive care (18,235) admissions and primary care registrations (460,000 inhabitants) between January 1997 and December 2012. INTERVENTIONS Hand-hygiene campaign; MRSA admission screening; antibiotic stewardship limiting use of macrolides and '4Cs' (cephalosporins, coamoxiclav, clindamycin and fluoroquinolones). OUTCOME MEASURES Prevalence density of MRSA clonal complexes CC22, CC30 and CC5/Other in hospital (isolates/1000 occupied bed days, OBDs) and community (isolates/10,000 inhabitant-days). RESULTS 67% of all clinical MRSA isolates (10,707/15,947) were typed. Regional MRSA population structure was dominated by hospital epidemic strains CC30, CC22 and CC45. Following declines in overall MRSA prevalence density, CC5 and other strains of community origin became increasingly important. Reductions in use of '4Cs' and macrolides anticipated declines in sublineages with higher levels of associated resistances. In multivariate time-series models (R(2)=0.63-0.94) introduction of the hand-hygiene campaign, reductions in mean length of stay (when >4 days) and bed occupancy (when >74 to 78%) predicted declines in CC22 and CC30, but not CC5/other strains. Lower importation pressures, expanded MRSA admission screening, and reductions in macrolide and third generation cephalosporin use (thresholds for association: 135-141, and 48-81 defined daily doses/1000 OBDs, respectively) were followed by declines in all clonal complexes. Strain-specific associations with fluoroquinolones and clindamycin reflected resistance phenotypes of clonal complexes. CONCLUSIONS Infection control measures and changes in population antibiotic use were important predictors of MRSA strain dynamics in our region. Strategies to control MRSA should consider thresholds for effects and strain-specific impacts.
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Affiliation(s)
- Timothy Lawes
- Department of Paediatrics, Royal Aberdeen Children's Hospital, Aberdeen, UK
| | | | - César Nebot
- Centro Universitario de la Defensa (CUD) de San Javier, Murcia, Murcia, Spain
| | | | | | - Ceri R J Dare
- Medical Microbiology Department, Aberdeen Royal Infirmary, Aberdeen, UK
| | | | - Ian M Gould
- Medical Microbiology Department, Aberdeen Royal Infirmary, Aberdeen, UK
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Abstract
BACKGROUND In the last decade, non-multiresistant methicillin-resistant Staphylococcus aureus (NM-MRSA) has been described as an important agent in bloodstream infections in our hospital. METHODS This prospective cohort study, conducted from February 2009 through January 2010 in the neonatal unit, evaluated 403 newborns (NB), their 382 mothers and 148 health care workers (HCW). RESULTS Approximately 217 NB (54%), 187 mothers (48%) and 87 HCW (59%) were colonized by S. aureus (SA). MRSA colonization was greater among NB (15%) than mothers (4.7%) and HCW (3.4%). Although mother-to-NB transmission occurred, in most cases mothers were not responsible for NB colonization. There were 2 predominant PFGE patterns among the NB and some mothers and HCW became colonized by them. Factors significantly associated with MRSA carriage by NB were lower level of maternal schooling (risk factor: odds ratio: 2.99; 95% confidence interval: 1.10-8.07) and maternal rhinosinusitis (protective factor: odds ratio: 0.33; 95% confidence interval:0.12-0.88). Among NB who remained hospitalized for more than 72 hours, breast feeding was protective (odds ratio: 0.22; 95% confidence interval: 0.05-0.98). All the isolates were NM-MRSA, carried few virulence factors and SCCmec types IVa and type IVd predominated. CONCLUSIONS Although there were no cases of infection, nosocomial transmission of MRSA clearly occurred in the neonatal unit, and this highlights the need for infection control practices such as hand hygiene to prevent cross-dissemination. Other healthcare practices, which are very basic but also ample in scope, may play a role, such as general education of women and breast feeding.
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Calderwood MS, Desjardins CA, Sakoulas G, Nicol R, Dubois A, Delaney ML, Kleinman K, Cosimi LA, Feldgarden M, Onderdonk AB, Birren BW, Platt R, Huang SS. Staphylococcal enterotoxin P predicts bacteremia in hospitalized patients colonized with methicillin-resistant Staphylococcus aureus. J Infect Dis 2013; 209:571-7. [PMID: 24041793 DOI: 10.1093/infdis/jit501] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Methicillin-resistant Staphylococcus aureus (MRSA) colonization predicts later infection, with both host and pathogen determinants of invasive disease. METHODS This nested case-control study evaluates predictors of MRSA bacteremia in an 8-intensive care unit (ICU) prospective adult cohort from 1 September 2003 through 30 April 2005 with active MRSA surveillance and collection of ICU, post-ICU, and readmission MRSA isolates. We selected MRSA carriers who did (cases) and those who did not (controls) develop MRSA bacteremia. Generating assembled genome sequences, we evaluated 30 MRSA genes potentially associated with virulence and invasion. Using multivariable Cox proportional hazards regression, we assessed the association of these genes with MRSA bacteremia, controlling for host risk factors. RESULTS We collected 1578 MRSA isolates from 520 patients. We analyzed host and pathogen factors for 33 cases and 121 controls. Predictors of MRSA bacteremia included a diagnosis of cancer, presence of a central venous catheter, hyperglycemia (glucose level, >200 mg/dL), and infection with a MRSA strain carrying the gene for staphylococcal enterotoxin P (sep). Receipt of an anti-MRSA medication had a significant protective effect. CONCLUSIONS In an analysis controlling for host factors, colonization with MRSA carrying sep increased the risk of MRSA bacteremia. Identification of risk-adjusted genetic determinants of virulence may help to improve prediction of invasive disease and suggest new targets for therapeutic intervention.
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Uzunović-Kamberović S, Rijnders MIA, Stobberingh EE, Ibrahimagić A, Kamberović F, Ille T. Molecular characterisation of methicillin-susceptible and methicillin-resistant Staphylococcus aureus in inpatients and outpatients in Bosnia and Herzegovina. Wien Med Wochenschr 2012; 163:13-20. [PMID: 23053564 DOI: 10.1007/s10354-012-0142-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 08/16/2012] [Indexed: 02/05/2023]
Abstract
The aim of this study was to investigate the genetic background of methicillin-susceptible (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA) obtained from clinical specimens of inpatients and outpatients. Methicillin resistance was confirmed by the presence of the mecA gene by PCR. The genetic characterisation was performed using spa typing and the algorithm based upon repeat pattern (BURP). Staphylococcus aureus was isolated from 68 and 79 inpatient and outpatient samples, 31 (46 %) and 14 (18 %) of which were MRSA, respectively. Among 37 inpatients and 65 outpatients with MSSA, 22 and 38 spa types were clustered into seven and eight spa-CCs, respectively. The main MSSA spa-CC of inpatients and outpatients was spa-CC015 (multilocus sequence typing (MLST) CC45). Most MRSA were associated with spa-CC355/595 (MLST CC152). MRSA-related background was found in 32 % of inpatients and 43 % of outpatients with MSSA, suggesting that MRSA did not arise from predominant MSSA clones.
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Affiliation(s)
- Selma Uzunović-Kamberović
- Department for Laboratory Diagnostics, Cantonal Public Health Institute Zenica, Fra Ivana Jukica 2, 72000, Zenica, Bosnia and Herzegovina.
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Campanile F, Bongiorno D, Falcone M, Vailati F, Pasticci MB, Perez M, Raglio A, Rumpianesi F, Scuderi C, Suter F, Venditti M, Venturelli C, Ravasio V, Codeluppi M, Stefani S. Changing Italian nosocomial-community trends and heteroresistance in Staphylococcus aureus from bacteremia and endocarditis. Eur J Clin Microbiol Infect Dis 2011; 31:739-45. [PMID: 21822974 PMCID: PMC3319882 DOI: 10.1007/s10096-011-1367-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Accepted: 07/14/2011] [Indexed: 12/20/2022]
Abstract
Bloodstream infections due to Staphylococcus aureus (BSI) are serious infections both in hospitals and in the community, possibly leading to infective endocarditis (IE). The use of glycopeptides has been recently challenged by various forms of low-level resistance. This study evaluated the distribution of MSSA and MRSA isolates from BSI and IE in 4 Italian hospitals, their antibiotic susceptibility—focusing on the emergence of hVISA—and genotypic relationships. Our results demonstrate that the epidemiology of MRSA is changing versus different STs possessing features between community-acquired (CA)- and hospital-acquired (HA)-MRSA groups; furthermore, different MSSA isolated from BSI and IE were found, with the same backgrounds of the Italian CA-MRSA. The hVISA phenotype was very frequent (19.5%) and occurred more frequently in isolates from IE and in both the MSSA and MRSA strains. As expected, hVISA were detected in MRSA with vancomycin minimum inhibitory concentrations (MICs) of 1–2 mg/l, frequently associated with the major SCCmec I and II nosocomial clones; this phenotype was also detected in some MSSA strains. The few cases of MR-hVISA infections evaluated in our study demonstrated that 5 out of 9 patients (55%) receiving a glycopeptide, died. Future studies are required to validate these findings in terms of clinical impact.
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Affiliation(s)
- F Campanile
- Department of Bio-Medical Sciences, Section of Microbiology, University of Catania, Via Androne 81, 95124, Catania (I), Italy
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Pacheco RL, Lobo RD, Oliveira MS, Farina EF, Santos CR, Costa SF, Padoveze MC, Garcia CP, Trindade PA, Quitério LM, Rivitti EA, Mamizuka EM, Levin AS. Methicillin-resistant Staphylococcus aureus (MRSA) carriage in a dermatology unit. Clinics (Sao Paulo) 2011; 66:2071-7. [PMID: 22189732 PMCID: PMC3226602 DOI: 10.1590/s1807-59322011001200012] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
OBJECTIVE The aim of this study was to characterize Staphylococcus aureus (MRSA) carriage in a dermatology unit. METHODS This was a prospective and descriptive study. Over the course of 26 weeks, surveillance cultures were collected weekly from the anterior nares and skin of all patients hospitalized in a 20-bed dermatology unit of a tertiary-care hospital. Samples from healthcare workers (HCWS) were cultured at the beginning and end of the study. Colonized patients were put under contact precautions, and basic infection control measures were enforced. Staphylococcus aureus colonization pressure was determined monthly. Colonized and non-colonized patients were compared, and isolates were evaluated for antimicrobial susceptibility, SCCmec type, virulence factors, and type. RESULTS Of the 142 patients evaluated, 64 (45%) were colonized by MRSA (39% hospital acquired; 25% community acquired; 36% indeterminate). Despite isolation precautions, hospital-acquired Staphylococcus aureus occurred in addition to the continuous entry of Staphylococcus aureus from the community. Colonization pressure increased from 13% to 59%, and pemphigus and other bullous diseases were associated with MRSA colonization. Eleven out of 71 HCWs (15%) were Staphylococcus aureus carriers, although only one worker carried a persistent clone. Of the hospital-acquired MRSA cases, 14/28 (50%) were SCCmec type IV (3 PFGE types), 13 were SCCmec type III (46%), and one had an indeterminate type. These types were also present among the community-acquired Staphylococcus aureus isolates. SSCmec type IV isolates were shown to be more susceptible than type III isolates. There were two cases of bloodstream infection, and the pvl and tst virulence genes were absent from all isolates. CONCLUSIONS Dermatology patients were colonized by community- and hospital-acquired Staphylococcus aureus. Half of the nosocomial Staphylococcus aureus isolates were SCCmec type IV. Despite the identification of colonized patients and the subsequent contact precautions and room placement, Staphylococcus aureus colonization continued to occur, and colonization pressure increased. Pemphigus and other bullous diseases were associated with Staphylococcus aureus.
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Affiliation(s)
- Renata L Pacheco
- Hospital das Clínicas da Universidade de São Paulo, Department of Infectious Diseases and LIM-54, São Paulo/SP, Brazil
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Blaine KP, Tuohy MJ, Wilson D, Procop GW, Tisch DJ, Shrestha NK, Hall GS. Progression to bacteremia in critical care patients colonized with methicillin-resistant Staphylococcus aureus expressing Panton-Valentine leukocidin. Diagn Microbiol Infect Dis 2010; 68:28-33. [PMID: 20727466 DOI: 10.1016/j.diagmicrobio.2010.04.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2009] [Revised: 04/25/2010] [Accepted: 04/29/2010] [Indexed: 11/30/2022]
Abstract
The role of Panton-Valentine leukocidin (PVL) in methicillin-resistant Staphylococcus aureus (MRSA) infections is unclear. PVL has been long associated with soft tissue infections and necrotizing pneumonia, but inconsistently with other site infections or mortality. The retrospective cohort study explores the association between PVL and bacteremia in colonized medical intensive care unit (ICU) patients with surveillance isolates and blood cultures. A total of 840 patients were screened by nasal swab, with 266 patients found to be colonized and 46 with bacteremia. Colonization by PVL(+) MRSA increased the odds of bacteremia (odds ratio, 2.40; confidence interval, 1.23-4.57), and invasive infection developed earlier in these patients (relative risk, 0.44; confidence interval 0.25-0.85) compared to those colonized with PVL(0) MRSA. PVL was not associated with infections at other sites, length of ICU stay, or mortality. PVL decreases the time to bacteremia in colonized patients but does not otherwise contribute to disease course or clinical outcome.
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Affiliation(s)
- Kevin P Blaine
- Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH 44195, USA.
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Management of Staphylococcus aureus bacteremia and endocarditis: progresses and challenges. Curr Opin Infect Dis 2010; 23:346-58. [DOI: 10.1097/qco.0b013e32833bcc8a] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Emergence of multiresistant variants of the community-acquired methicillin-resistant Staphylococcus aureus lineage ST1-SCCmecIV in 2 hospitals in Rio de Janeiro, Brazil. Diagn Microbiol Infect Dis 2009; 65:300-5. [PMID: 19748199 DOI: 10.1016/j.diagmicrobio.2009.07.023] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2009] [Revised: 07/17/2009] [Accepted: 07/26/2009] [Indexed: 11/21/2022]
Abstract
Usually, community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is susceptible to a variety of non-beta-lactam drugs. These isolates commonly display SCCmecIV and are associated with community-acquired infections. More recently, CA-MRSA has been isolated from health-care-associated diseases. We characterized MRSA isolates from 2 hospitals in Rio de Janeiro area to assess the entry of new lineages. The isolates were primary genotyped using a combination of molecular typing methods including SCCmec, restriction modification test, and Panton-Valentine leukocidin (PVL) detection. Pulsed-field gel electrophoresis was carried out for representatives of each lineages found. Disk diffusion test was performed as recommended by the Clinical and Laboratory Standards Institute. SCCmecIV was the predominant cassette mec detected. The most frequent MRSA lineage, a PVL nonproducer, was allocated in the CC1-SCCmecIV. It was found that 56% of these isolates were resistant to 3 or more non-beta-lactam drugs. Multilocus sequence typing of a representative of the CC1 isolates supported our finds that multiresistant variants of a CA-MRSA lineage (ST1-SCCmecIV) emerged in this city.
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