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Torkar KG, Ivić S. Surveillance of bacterial colonisation on contact surfaces in different medical wards. Arh Hig Rada Toksikol 2018; 68:116-126. [PMID: 28665797 DOI: 10.1515/aiht-2017-68-2892] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2016] [Accepted: 05/01/2017] [Indexed: 11/15/2022] Open
Abstract
This study was conducted to determine the bacterial colonization of some bacterial groups, including extended-spectrum β-lactamase (ESBLs) producers and methicillin-resistant Staphylococcus aureus (MRSA), on surfaces of the equipment and instruments in patient rooms and other workspaces in three different medical wards. The number of microorganisms on swabs was determined with the colony count method on selective microbiological mediums. The aerobic mesophylic microorganisms were found in 73.5 % out of 102 samples, with the average and maximum values of 2.6 × 102 and 4.6 × 103 colony forming units (CFU) 100 cm-2, respectively. Members of the family Enterobacteriaceae, coagulase positive staphylococci, coagulase-negative staphylococci, and enterococci were detected in 23.4, 31.4, 53.2, and 2.9 % of samples, respectively. The differences in bacterial counts on the surfaces of the psychiatric, oncology, and paediatric wards were statistically significant (P<0.001). About 40 % out of 19 isolates from the family Enterobacteriaceae showed multiple resistance to three or more different groups of tested antibiotics, while ESBL was confirmed for only one strain. Staphylococci isolates were mostly resistant to penicillin. MRSA was confirmed in 5.2 % of the tested S. aureus isolates. Greater attention should be paid to cleaning and the appropriate choice of disinfectants, especially in the psychiatric ward. Employees should be informed about the prevention of the spreading of nosocomial infections. Routine application of rapid methods for hygiene control of surfaces is highly recommended.
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Yoon EJ, Yang JW, Kim JO, Lee H, Lee KJ, Jeong SH. Carbapenemase-producing Enterobacteriaceae in South Korea: a report from the National Laboratory Surveillance System. Future Microbiol 2018; 13:771-783. [PMID: 29478336 DOI: 10.2217/fmb-2018-0022] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
AIM To assess the epidemiology of carbapenemase-producing Enterobacteriaceae (CPE) in South Korea. MATERIALS & METHODS From 2011 to 2015, 2487 carbapenem-nonsusceptible Enterobacteriaceae were collected through the Korean National Laboratory Surveillance System. Disk-diffusion for antimicrobial susceptibility, PCR/sequencing to detect carbapenemase genes and multilocus sequence typing for molecular epidemiology were carried out. RESULTS The number of carbapenem-nonsusceptible Enterobacteriaceae was increasing approximately 1.5-fold per year and the proportion of CPEs was exponentially confirmed from 2014. KPC was the most dominant, mostly associated with Klebsiella pneumoniae ST11 and ST307, NDM was the second and OXA-48-like was the third dominant carbapenemases. The IMP, VIM and GES-5 CPEs were identified sporadically. CONCLUSION The nation-wide spreads of KPC, NDM and OXA-48-like CPEs were in an alarming epidemiological stage.
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Affiliation(s)
- Eun-Jeong Yoon
- Department of Laboratory Medicine & Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
| | - Ji Woo Yang
- Division of Antimicrobial Resistance, National Institute of Health, Centers for Disease Control & Prevention, Cheongju, South Korea
| | - Jung Ok Kim
- Department of Laboratory Medicine & Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
| | - Hyukmin Lee
- Department of Laboratory Medicine & Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
| | - Kwang Jun Lee
- Division of Antimicrobial Resistance, National Institute of Health, Centers for Disease Control & Prevention, Cheongju, South Korea
| | - Seok Hoon Jeong
- Department of Laboratory Medicine & Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, South Korea
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Park C, Lee HJ, Seo MY. The Characteristics of Imipenem-Resistant Bacteria Isolated from One Patient. KOREAN JOURNAL OF CLINICAL LABORATORY SCIENCE 2017. [DOI: 10.15324/kjcls.2017.49.4.413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Chul Park
- Department of Clinical Laboratory Science, Gwangyang Health Science University, Gwangyang, Korea
| | - Hyeok-Jae Lee
- Department of Biomedical Laboratory Science, Gwangju Health Science University, Gwangju, Korea
| | - Min-Young Seo
- Department of Biomedical Laboratory Science, Gwangju Health Science University, Gwangju, Korea
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Bae IK, Kang HK, Jang IH, Lee W, Kim K, Kim JO, Jeong SH, Lee K. Detection of Carbapenemases in Clinical Enterobacteriaceae Isolates Using the VITEK AST-N202 Card. Infect Chemother 2015; 47:167-74. [PMID: 26483990 PMCID: PMC4607769 DOI: 10.3947/ic.2015.47.3.167] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 06/02/2015] [Accepted: 06/03/2015] [Indexed: 12/25/2022] Open
Abstract
Background The rapid and accurate detection of carbapenemase-producing Enterobacteriaceae (CPE) in clinical microbiology laboratories is essential for the treatment and control of infections caused by these microorganisms. This study was performed to evaluate the ability of the VITEK AST-N202 card to detect CPE isolates. Materials and Methods A total of 43 (Klebsiella pneumoniae, n = 37; Escherichia coli, n = 3; and Enterobacter cloacae, n = 3) CPE isolates and 79 carbapenemase-non-producing Enterobacteriaceae (CNE) isolates were included in this study. The CPE isolates harbored KPC-2 (n = 11), KPC-3 (n = 20), GES-5 (n = 5), VIM-2 (n = 2), IMP-1 (n = 1), NDM-1 (n = 2), or OXA-232 (n = 2). Of the 79 CNE isolates, eight K. pneumoniae isolates were resistant to ertapenem, imipenem, and meropenem, while the remaining 71 isolates were susceptible to the carbapenems. Antimicrobial susceptibilities were tested using the VITEK AST-N202 card, and the results were interpreted as positive when the isolates showed resistant or intermediate results. Modified-Hodge tests (MHTs) were performed using ertapenem or meropenem disks for the screening of carbapenemase production. Polymerase chain reaction (PCR) and direct sequencing were used to identify β-lactamase genes. Results Sensitivity of MHT with ertapenem and meropenem disks for the detection of carbapenemase was 81.4% (35/43) and 81.4% (35/43), respectively, and a combination with both antibiotic disks increased the sensitivity to 88.4% (38/43). Specificity of the MHT was 100% (79/79) for the CNE isolates. Sensitivity of ertapenem, imipenem, and meropenem as assessed by the VITEK AST-N202 card was 100% (43/43), 93% (40/43), and 95.3% (41/43), respectively. Specificity (89.8%, 71/79) of the test with each carbapenem was improved to 100% (71/71) when eight carbapenem-resistant CNE isolates were excluded from the testing. Conclusion The VITEK AST-N202 card showed high sensitivity for the detection of carbapenemases in Enterobacteriaceae strains. PCR and sequencing experiments for the detection of carbapenemases are recommended when clinical Enterobacteriaceae isolates show non-susceptibility to carbapenems.
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Affiliation(s)
- Il Kwon Bae
- Department of Dental Hygiene, Silla University, Busan, Korea
| | - Hyun-Kyung Kang
- Department of Dental Hygiene, Silla University, Busan, Korea
| | - In-Ho Jang
- Department of Biomedical Laboratory Science, College of Health Sciences, Sangji University, Wonju, Gangwon, Korea
| | - Woonhyoung Lee
- Department of Laboratory Medicine, Kosin University College of Medicine, Busan, Korea
| | - Keonhan Kim
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
| | - Jung Ok Kim
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
| | - Seok Hoon Jeong
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
| | - Kyungwon Lee
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
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Neonakis I, Messaritakis H, Stafylaki D, Maraki S. First detection of a metallo-β-lactamase producing Serratia marcescens in a European university hospital. Indian J Med Microbiol 2014; 32:352-3. [PMID: 25008843 DOI: 10.4103/0255-0857.136615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
| | | | | | - S Maraki
- Department of Bacteriology Parasitology Zoonoses and Geographical Medicine, Heraklion, Crete, Greece
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Yoo JS, Kim HM, Yoo JI, Yang JW, Kim HS, Chung GT, Lee YS. Detection of clonal KPC-2-producing Klebsiella pneumoniae ST258 in Korea during nationwide surveillance in 2011. J Med Microbiol 2013; 62:1338-1342. [PMID: 23741020 DOI: 10.1099/jmm.0.059428-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This study analysed the characteristics and genetic similarity of recent Klebsiella pneumoniae carbapenemase (KPC-2)-producing Klebsiella pneumoniae isolates from Korea. Recent laboratory surveillance detected an increase in carbapenemase-producing Enterobacteriaceae in Korea. A total of 6 KPC-2-producing K. pneumoniae were identified from 277 Enterobacteriaceae clinical isolates. All were sequence type (ST) 258 and they had the same pulsotype. They had high MICs for carbapenems and multi-drug resistance. TEM-1, SHV-11 and OXA type β-lactamases were detected in all isolates, whereas CTX-M type β-lactamases and plasmid-mediated AmpC β-lactamase (PABL) were not present. A conjugation experiment failed, but blaKPC-2-harbouring plasmids from the six isolates were used to transform Escherichia coli DH5-α by electroporation. Each of the transformants harboured a blaKPC-2-positive approximately 95 kb plasmid, which was typed in the IncFII incompatibility group and co-harboured TEM-1 and OXA-9 β-lactamases. They shared the same restriction profile. This study confirms the emergence of clonal ST258 KPC-2-producing K. pneumoniae in some regions of Korea.
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Affiliation(s)
- Jung Sik Yoo
- Division of Antimicrobial Resistance, Korea National Institute of Health, 187 Osong Saengmyeong 2-ro Chungcheongbuk-do, 363-951, Republic of Korea
| | - Hye Mee Kim
- Division of Antimicrobial Resistance, Korea National Institute of Health, 187 Osong Saengmyeong 2-ro Chungcheongbuk-do, 363-951, Republic of Korea
| | - Jae Il Yoo
- Division of Antimicrobial Resistance, Korea National Institute of Health, 187 Osong Saengmyeong 2-ro Chungcheongbuk-do, 363-951, Republic of Korea
| | - Ji Woo Yang
- Division of Antimicrobial Resistance, Korea National Institute of Health, 187 Osong Saengmyeong 2-ro Chungcheongbuk-do, 363-951, Republic of Korea
| | - Hwa Su Kim
- Division of Antimicrobial Resistance, Korea National Institute of Health, 187 Osong Saengmyeong 2-ro Chungcheongbuk-do, 363-951, Republic of Korea
| | - Gyung Tae Chung
- Division of Enteric Bacterial Infections, Korea National Institute of Health, 187 Osong Saengmyeong 2-ro Chungcheongbuk-do, 363-951, Republic of Korea
| | - Yeong Seon Lee
- Division of Antimicrobial Resistance, Korea National Institute of Health, 187 Osong Saengmyeong 2-ro Chungcheongbuk-do, 363-951, Republic of Korea
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Lim Y, Lee Y, Seo Y, Yum JH, Yong D, Lee K, Chong Y. Loss of blaVIM-2and blaIMP-1during the Storage of Gram-Negative Bacilli, Antimicrobial Susceptibility of the Gene-Lost Strain, and Location of the Gene in the Cell. ANNALS OF CLINICAL MICROBIOLOGY 2013. [DOI: 10.5145/acm.2013.16.3.120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Youngsik Lim
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
| | - Yangsoon Lee
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
- Department of Laboratory Medicine, National Health Insurance Corporation Ilsan Hospital, Goyang, Korea
| | - Younghee Seo
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
| | - Jong Hwa Yum
- Department of Clinical Laboratory Science, Dong-eui University, Busan, Korea
| | - Dongeun Yong
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
| | - Kyungwon Lee
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
| | - Yunsop Chong
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
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Emergence of metallo-β-lactamase GIM-1 in a clinical isolate of Serratia marcescens. Antimicrob Agents Chemother 2012; 56:4945-7. [PMID: 22710114 DOI: 10.1128/aac.00405-12] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The metallo-β-lactamase GIM-1 (German imipenemase) has been found so far only in clinical isolates of Pseudomonas aeruginosa from Germany. Here we report the detection of bla(GIM-1) in a clinical strain of Serratia marcescens that was isolated from urine, blood, and wound samples over a period of 20 months. The strain was repeatedly isolated from one patient in two German hospitals and an outpatient department located in the region in which all previously described GIM-1-producing P. aeruginosa strains were identified.
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Abstract
Serratia species, in particular Serratia marcescens, are significant human pathogens. S. marcescens has a long and interesting taxonomic, medical experimentation, military experimentation, and human clinical infection history. The organisms in this genus, particularly S. marcescens, were long thought to be nonpathogenic. Because S. marcescens was thought to be a nonpathogen and is usually red pigmented, the U.S. military conducted experiments that attempted to ascertain the spread of this organism released over large areas. In the process, members of both the public and the military were exposed to S. marcescens, and this was uncovered by the press in the 1970s, leading to U.S. congressional hearings. S. marcescens was found to be a certain human pathogen by the mid-1960s. S. marcescens and S. liquefaciens have been isolated as causative agents of numerous outbreaks and opportunistic infections, and the association of these organisms with point sources such as medical devices and various solutions given to hospitalized patients is striking. Serratia species appear to be common environmental organisms, and this helps to explain the large number of nosocomial infections due to these bacteria. Since many nosocomial infections are caused by multiply antibiotic-resistant strains of S. marcescens, this increases the danger to hospitalized patients, and hospital personnel should be vigilant in preventing nosocomial outbreaks due to this organism. S. marcescens, and probably other species in the genus, carries several antibiotic resistance determinants and is also capable of acquiring resistance genes. S. marcescens and S. liquefaciens are usually identified well in the clinical laboratory, but the other species are rare enough that laboratory technologists may not recognize them. 16S rRNA gene sequencing may enable better identification of some of the less common Serratia species.
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Emergence of resistance to antibacterial agents: the role of quaternary ammonium compounds--a critical review. Int J Antimicrob Agents 2012; 39:381-9. [PMID: 22421329 DOI: 10.1016/j.ijantimicag.2012.01.011] [Citation(s) in RCA: 349] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Accepted: 01/12/2012] [Indexed: 12/11/2022]
Abstract
Quaternary ammonium compounds (QACs) are widely distributed in hospitals, industry and cosmetics. Little attention has been focused on the potential impact of QACs on the emergence of antibiotic resistance in patients and the environment. To assess this issue, we conducted a literature review on QAC chemical structure, fields of application, mechanism of action, susceptibility testing, prevalence, and co- or cross-resistance to antibiotics. Special attention was paid to the effects of QACs on microflora; in particular, the issue of the potential of QACs for applying selective pressure on multiple-antibiotic-resistant organisms was raised. It was found that there is a lack of standardised procedures for interpreting susceptibility test results. QACs have different impacts on the minimum inhibitory concentrations of antibacterials depending on the antibacterial compound investigated, the resistance genes involved, the measuring methodology and the interpretative criteria. The unmet needs for adequate detection of reduced susceptibility to QACs and antibiotics include (i) a consensus definition for resistance, (ii) epidemiological cut-off values and (iii) clinical resistance breakpoints. This review advocates the design of international guidelines for QAC use.
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Yum J, Shin HB, Yong D, Chong Y. Diversity of Integrons CarryingblaVIM-2Cassette inPseudomonasspp. andAcinetobacterspp. ACTA ACUST UNITED AC 2012. [DOI: 10.5145/kjcm.2012.15.4.131] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Jonghwa Yum
- Department of Clinical Laboratory Science, College of Nursing and Healthcare Sciences, Dong-eui University, Busan, Korea
| | - Hee Bong Shin
- Department of Laboratory Medicine, Soonchunhyang University Hospital, Bucheon, Korea
| | - Dongeun Yong
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, College of Medicine, Yonsei University, Seoul, Korea
| | - Yunsop Chong
- Department of Laboratory Medicine and Research Institute of Bacterial Resistance, College of Medicine, Yonsei University, Seoul, Korea
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13
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Zhao WH, Hu ZQ. Epidemiology and genetics of VIM-type metallo-β-lactamases in Gram-negative bacilli. Future Microbiol 2011; 6:317-33. [DOI: 10.2217/fmb.11.13] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Metallo-β-lactamases (MBLs) are a rapidly evolving group of β-lactamases, which hydrolyze most β-lactams including the carbapenems. Of the known MBLs, VIMs are one of the most common families, with 27 variants detected in at least 23 species of Gram-negative bacilli from more than 40 countries/regions. The amino acid similarities of VIM variants range from 72.9 to 99.6% with 1–72 different residues. Most of the bla VIMs are harbored by a class 1 integron, a genetic platform able to acquire and express gene cassettes. The integrons are usually embedded in transposons and, in turn, accommodated on plasmids, making them highly mobile. Integrons display considerable diversity, with at least 110 different structures associated with the gain and spread of the bla VIMs. In most instances, the bla VIMs co-exist with one or more other resistance genes. The processes for the identification of bacteria harboring bla VIMs are also discussed in this article.
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Affiliation(s)
| | - Zhi-Qing Hu
- Department of Microbiology & Immunology, Showa University School of Medicine, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142–8555, Japan
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Jeong HW, Son BR, Shin DI, Ryu D, Hong SB, Han K, Shin KS. Characterization ofAcinetobacter baumanniiCo-producing Carbapenemases OXA-23 and OXA-66, andarmA16S Ribosomal RNA Methylase at a University Hospital in South Korea. ACTA ACUST UNITED AC 2011. [DOI: 10.5145/kjcm.2011.14.2.67] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Hye Won Jeong
- Department of Internal Medicine, College of Medicine, Chungbuk National University, Cheongju, Korea
| | - Bo Ra Son
- Department of Laboratory Medicine, College of Medicine, Chungbuk National University, Cheongju, Korea
| | - Dong Ick Shin
- Department of Neurology, College of Medicine, Chungbuk National University, Cheongju, Korea
| | - Donghee Ryu
- Department of Surgery, College of Medicine, Chungbuk National University, Cheongju, Korea
| | - Seung Bok Hong
- Department of Clinical Laboratory Science, Juseong University, Cheongwon, Korea
| | - Kyudong Han
- Department of Microbiology and Institute of Basic Science, Dankook University, Cheonan, Korea
| | - Kyeong Seob Shin
- Department of Laboratory Medicine, College of Medicine, Chungbuk National University, Cheongju, Korea
- BK 21 Chungbuk Biomedical Science Center, College of Medicine, Chungbuk National University, Cheongju, Korea
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Lee K. Trend of Bacterial Resistance for the Past 50 Years in Korea and Future Perspectives - Gram-negative Bacteria. Infect Chemother 2011. [DOI: 10.3947/ic.2011.43.6.458] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Kyungwon Lee
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, Korea
- Research Institute of Bacterial Resistance, Yonsei University College of Medicine, Seoul, Korea
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Determination of Some Chemical Parameters and Antimicrobial Activity of Traditional Food: Mesir Paste. J Med Food 2010; 13:1195-202. [DOI: 10.1089/jmf.2009.0209] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Outbreak of meropenem-resistant Serratia marcescens comediated by chromosomal AmpC beta-lactamase overproduction and outer membrane protein loss. Antimicrob Agents Chemother 2010; 54:5057-61. [PMID: 20876374 DOI: 10.1128/aac.00768-10] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The aim of this study was to investigate the mechanisms involved in the meropenem resistance of Serratia marcescens clinical isolates. Meropenem-resistant (MIC range, 16 to 32 μg/ml) S. marcescens isolates were recovered from nine patients in a tertiary hospital in Seoul, South Korea, from June to November 2005. All the isolates shared identical or similar (>85% similarity) SpeI macrorestriction patterns, indicating clonal spread. PCR experiments did not detect any carbapenemase in those isolates. They carried the bla(CTX-M-22) gene located on a 150-kbp plasmid of the incompatibility group L/M; however, the addition of clavulanic acid exhibited few effects on meropenem MICs. Although meropenem MICs were reduced 4- to 16-fold with the addition of boronic acid, no plasmid-borne AmpC β-lactamase gene was detected in PCR experiments. Real-time quantitative PCR experiments showed that expression levels of the chromosomal ampC gene in those isolates were 87.06 to 155.76 times higher than that of the reference strain ATCC 8100. SDS-PAGE showed a lack of the 42-kDa outer membrane protein (OmpF). In combination with the overproduction of the chromosomal AmpC enzyme, the loss of OmpF may have played a role in the acquisition of meropenem resistance in our isolates.
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Hegstad K, Langsrud S, Lunestad BT, Scheie AA, Sunde M, Yazdankhah SP. Does the wide use of quaternary ammonium compounds enhance the selection and spread of antimicrobial resistance and thus threaten our health? Microb Drug Resist 2010; 16:91-104. [PMID: 20370507 DOI: 10.1089/mdr.2009.0120] [Citation(s) in RCA: 234] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Quaternary ammonium compounds (QACs) are widely used biocides that possess antimicrobial effect against a broad range of microorganisms. These compounds are used for numerous industrial purposes, water treatment, antifungal treatment in horticulture, as well as in pharmaceutical and everyday consumer products as preserving agents, foam boosters, and detergents. Resistance toward QACs is widespread among a diverse range of microorganisms and is facilitated by several mechanisms such as modifications in the membrane composition, expression of stress response and repair systems, or expression of efflux pump genes. Development of resistance in both pathogenic and nonpathogenic bacteria has been related to application in human medicine and the food industry. QACs in cosmetic products will inevitably come into intimate contact with the skin or mucosal linings in the mouth and thus are likely to add to the selection pressure toward more QAC-resistant microorganisms among the skin or mouth flora. There is increasing evidence of coresistance and cross-resistance between QACs and a range of other clinically important antibiotics and disinfectants. Use of QACs may have driven the fixation and spread of certain resistance cassette collectors (class 1 integrons), currently responsible for a major part of antimicrobial resistance in gram-negative bacteria. More indiscriminate use of QACs such as in cosmetic products may drive the selection of further new genetic elements that will aid in the persistence and spread of antimicrobial resistance and thus in limiting our treatment options for microbial infections.
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Affiliation(s)
- Kristin Hegstad
- Department of Microbiology and Infection Control, Reference Centre for Detection of Antimicrobial Resistance, University Hospital of North Norway, Tromsø, Norway.
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Shahid M, Sobia F, Singh A, Malik A, Khan HM, Jonas D, Hawkey PM. Beta-lactams and beta-lactamase-inhibitors in current- or potential-clinical practice: a comprehensive update. Crit Rev Microbiol 2009; 35:81-108. [PMID: 19514910 DOI: 10.1080/10408410902733979] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The use of successive generations of beta-lactams has selected successive generations of beta-lactamases including CTX-M ESBLs, AmpC beta-lactamases, and KPC carbapenamases in Enterobacteriaceae. Moreover, this cephalosporin resistance, along with rising resistance to fluoroquinolones, is now driving the use of carbapenems and unfortunately the carbapenem resistance has emerged markedly, especially in Acinetobacter spp. due to OXA- and metallo-carbapenemases. The industry responded to the challenge of rising resistance and recently developed some novel beta-lactams such as ceftobiprole, ceftaroline etc. and many beta-lactam compounds, including beta-lactamase-inhibitors, such as BMS-247243, S-3578, RWJ-54428, CS-023, SMP-601, NXL 104, BAL 30376, LK 157, and so on are under trials. This review provides the comprehensive accounts of the developments in penicillins, cephalosporins, carbapenems, and beta-lactamase-inhibitors, and the insight about medicinal chemistry, mechanism(s) of action and resistance, potential strategies to overcome resistance due to beta-lactamases, and also the recent advancements in the development of newer beta-lactam compounds; some of which are still under trials and yet to be classified. This review will fill the gap since previously published reviews and will serve as a comprehensive update on the current topic.
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Affiliation(s)
- M Shahid
- Section of Antimicrobial Resistance Researches and Molecular Biology, Department of Microbiology, Jawaharlal Nehru Medical College & Hospital, Aligarh Muslim University, Aligarh-202002, Uttar Pradesh, India.
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Gupta V. Metallo beta lactamases in Pseudomonas aeruginosa and Acinetobacter species. Expert Opin Investig Drugs 2008; 17:131-43. [PMID: 18230049 DOI: 10.1517/13543784.17.2.131] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The multi drug resistant gram negative bacteria especially Pseudomonas aeruginosa and Acinetobacter species are on the rise. The major defense in these bacteria against beta-lactam antibiotics is production of metallo beta lactamases (MBLs) which degrade this group of antibiotics including carbapenems. Till now five main types of MBLs have been described throughout the World--IMP, VIM, SPM, GIM and SIM. A new MBL has been recently reported in P. aeruginosa from Australia--bla AIM-1. There are no standard guidelines by CLSI for detection of these enzymes in various bacteria. A number of phenotypic tests based on different beta lactam-inhibitor combinations are being evaluated and used for routine testing. Regarding the treatment options--colistin, various antibiotic combinations and a few novel antibiotics are being tried and evaluated. Prevention is based on age old practices of strict infection control and judicious use of antibiotics.
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Affiliation(s)
- Varsha Gupta
- Government Medical College and Hospital, Department of Microbiology, Sector 32, Chandigarh-160030, India.
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21
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Outbreak caused by a multidrug-resistant Klebsiella pneumoniae clone carrying blaVIM-12 in a university hospital. J Clin Microbiol 2008; 46:1005-8. [PMID: 18199780 DOI: 10.1128/jcm.01573-07] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
From November 2006 to April 2007, nine nonrepetitive isolates of Klebsiella pneumoniae with reduced susceptibility or resistance to carbapenems were recovered from clinical specimens from separate patients hospitalized in a tertiary care hospital. The imipenem-EDTA synergy test was positive for all isolates. PCR, sequencing, and transferability experiments revealed the novel bla(VIM-12) metallo-beta-lactamase gene, which was plasmid mediated and located in a class 1 integron. Pulsed-field gel electrophoresis demonstrated a single macrorestriction pattern, indicating the clonal spread of VIM-12-producing K. pneumoniae.
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Młynarczyk A, Młynarczyk G, Pupek J, Bilewska A, Kawecki D, Łuczak M, Gozdowska J, Durlik M, Paczek L, Chmura A, Rowińnski W. Serratia marcescens isolated in 2005 from clinical specimens from patients with diminished immunity. Transplant Proc 2008; 39:2879-82. [PMID: 18022007 DOI: 10.1016/j.transproceed.2007.08.046] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Serratia marcescens is an important agent in hospital infections. The aim of this paper was to compare the resistance patterns of S. marcescens strains isolated during 1 year from patients of various wards of the Institute of Transplantology. The mechanisms of beta-lactam antibiotic resistance were of especial interest. We investigated the 81 strains of S. marcescens, isolated during 2005 from patients on 3 wards and 1 clinic of the Transplantation Institute. An unusually high resistance to most antibiotics was observed among S. marcescens strains. Extended spectrum beta-lactamases (ESBLs) were probably produced by 63.2% to 84.6% of strains, depending on the ward. Additionally, about 30% of them were probably derepressed AmpC producers. The patterns of resistance indicated that at least 2 resistant clones of S. marcescens spread among the patients. One of the clones demonstrated both ESBL and derepressed AmpC production and was susceptible only to carbapenems. The second, producing ESBL, was susceptible to piperacillin/tazobactam and carbapenems. All investigated strains were resistant to nitrofurantoin. Strains of the second group were rarely susceptible to other antibiotics: aminoglycosides, ciprofloxacin, cotrimoxazole, or fosfomycin.
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Affiliation(s)
- A Młynarczyk
- Department of Medical Microbiology, Warsaw Medical University, Warsaw, Poland.
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Abstract
Carbapenemases are beta-lactamases with versatile hydrolytic capacities. They have the ability to hydrolyze penicillins, cephalosporins, monobactams, and carbapenems. Bacteria producing these beta-lactamases may cause serious infections in which the carbapenemase activity renders many beta-lactams ineffective. Carbapenemases are members of the molecular class A, B, and D beta-lactamases. Class A and D enzymes have a serine-based hydrolytic mechanism, while class B enzymes are metallo-beta-lactamases that contain zinc in the active site. The class A carbapenemase group includes members of the SME, IMI, NMC, GES, and KPC families. Of these, the KPC carbapenemases are the most prevalent, found mostly on plasmids in Klebsiella pneumoniae. The class D carbapenemases consist of OXA-type beta-lactamases frequently detected in Acinetobacter baumannii. The metallo-beta-lactamases belong to the IMP, VIM, SPM, GIM, and SIM families and have been detected primarily in Pseudomonas aeruginosa; however, there are increasing numbers of reports worldwide of this group of beta-lactamases in the Enterobacteriaceae. This review updates the characteristics, epidemiology, and detection of the carbapenemases found in pathogenic bacteria.
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Affiliation(s)
- Anne Marie Queenan
- Johnson & Johnson Pharmaceutical Research & Development, L.L.C., Raritan, NJ 08869, USA.
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Kim SY, Park YJ, Yu JK, Kim HS, Park YS, Yoon JB, Yoo JY, Lee K. Prevalence and mechanisms of decreased susceptibility to carbapenems in Klebsiella pneumoniae isolates. Diagn Microbiol Infect Dis 2007; 57:85-91. [PMID: 16854555 DOI: 10.1016/j.diagmicrobio.2006.05.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2005] [Revised: 05/11/2006] [Accepted: 05/11/2006] [Indexed: 11/26/2022]
Abstract
In this study, we examined the prevalence of and mechanisms of decreased susceptibility to either imipenem or meropenem in Klebsiella pneumoniae isolates. A total of 230 clinical isolates of K. pneumoniae were collected from 13 clinical laboratories from a nationwide distribution. The MICs of imipenem and meropenem were determined by the agar dilution method. To characterize the isolates with decreased susceptibility to carbapenems (MICs of >2 microg/mL), we performed polymerase chain reaction amplification of a variety of beta-lactamase genes, isoelectric focusing, and outer membrane profile analysis using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and mass spectrometry. Three isolates (BD6, BD8, and KN16) exhibited decreased susceptibility to carbapenems with imipenem MICs of 1, 4, and 8 microg/mL and meropenem MICs of 4, 8, and 4, respectively. Isolate BD6 produced bla(TEM-1), bla(SHV-12), and bla(OXA-17); isolate BD8 produced bla(GES-3), bla(SHV-12), and bla(OXA-17); and isolate KN16 produced bla(TEM-11), bla(SHV-12), and bla(DHA-1). In all the 3 isolates, OmpK35 porin was not expressed, and in 1 isolate (KN16), OmpK36 was not expressed either. The prevalence of decreased susceptibility to carbapenems was low (1.3%), and none of them showed overt resistance to carbapenems. Decreased susceptibility to carbapenems can occur in K. pneumoniae when bla(GES-3), bla(TEM-11), bla(SHV-12), bla(OXA-17), and/or bla(DHA-1) are produced in combination with porin loss. In addition, to our knowledge, this is the 1st report of bla(OXA-17) in Enterobacteriaceae.
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Affiliation(s)
- Soo-Young Kim
- Department of Clinical Pathology, College of Medicine, The Catholic University of Korea, St. Vincent's Hospital, Suwon 442-723, South Korea
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25
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Yong D, Choi YS, Roh KH, Kim CK, Park YH, Yum JH, Lee K, Chong Y. Increasing prevalence and diversity of metallo-beta-lactamases in Pseudomonas spp., Acinetobacter spp., and Enterobacteriaceae from Korea. Antimicrob Agents Chemother 2006; 50:1884-6. [PMID: 16641469 PMCID: PMC1472216 DOI: 10.1128/aac.50.5.1884-1886.2006] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Among imipenem-nonsusceptible isolates, acquired metallo-beta-lactamase genes were detected in 36 of 581 (6.2%) Pseudomonas aeruginosa isolates, 42 of 44 (95.4%) other Pseudomonas species, and 136 of 513 (26.5%) Acinetobacter species from 2003 to 2004 at a Korean hospital. Overall, bla(VIM-2)-like genes were the most prevalent and were also detected in Enterobacteriaceae, including Klebsiella pneumoniae.
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Affiliation(s)
- Dongeun Yong
- Department of Laboratory Medicine, Yonsei University College of Medicine, 134 Shinchondong, Seodaemunku, Seoul 120-752, Korea
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26
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Lee HK, Park YJ, Kim JY, Chang E, Cho SG, Chae HS, Kang CS. Prevalence of decreased susceptibility to carbapenems among Serratia marcescens, Enterobacter cloacae, and Citrobacter freundii and investigation of carbapenemases. Diagn Microbiol Infect Dis 2006; 52:331-6. [PMID: 15994052 DOI: 10.1016/j.diagmicrobio.2005.04.012] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2005] [Accepted: 04/28/2005] [Indexed: 10/25/2022]
Abstract
Between March and July 2002, total of 612 clinical isolates of Serratia marcescens, Enterobacter cloacae, and Citrobacter freundii (201 S. marcescens, 228 E. cloacae, and 183 C. freundii) were collected from 13 clinical laboratories in a nationwide distribution. Imipenem and meropenem minimum inhibitory concentrations (MICs) were determined using the agar dilution method according to the National Committee for Clinical Laboratory Standards guidelines. For the isolates with a decreased susceptibility to carbapenems (MICs of >or=2 microg/mL), isoelectric focusing, polymerase chain reaction (PCR) amplification of the carbapenemase genes (bla(IMP-1), bla(VIM-2), bla(SME-1), bla(OXA-23), bla(OXA-25), bla(KPC-1)), and sequencing were performed. The prevalence of S. marcescens, E. cloacae, and C. freundii with a decreased susceptibility to imipenem was 17.9% (36/201), 0.4% (1/228), and 0.5% (1/183), respectively, and to meropenem, it was 11.4% (23/201), 0% (0/228), and 0.5% (1/183), respectively. The bla(VIM-2) was the only carbapenemase detected, and was found in 0.5% (1/201) of S. marcescens and 0.5% (1/183) of C. freundii isolate.
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Affiliation(s)
- Hae Kyung Lee
- Department of Clinical Pathology, College of Medicine, The Catholic University of Korea, Kangnam St. Mary's Hospital, Seoul 137-040, Republic of Korea
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27
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Gootz TD. The forgotten Gram-negative bacilli: what genetic determinants are telling us about the spread of antibiotic resistance. Biochem Pharmacol 2005; 71:1073-84. [PMID: 16359640 DOI: 10.1016/j.bcp.2005.11.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2005] [Revised: 10/28/2005] [Accepted: 11/04/2005] [Indexed: 11/16/2022]
Abstract
Gram-negative bacilli have become increasingly resistant to antibiotics over the past 2 decades due to selective pressure from the extensive use of antibiotics in the hospital and community. In addition, these bacteria have made optimum use of their innate genetic capabilities to extensively mutate structural and regulatory genes of antibiotic resistance factors, broadening their ability to modify or otherwise inactivate antibiotics in the cell. The great genetic plasticity of bacteria have permitted the transfer of resistance genes on plasmids and integrons between bacterial species allowing an unprecedented dissemination of genes leading to broad-spectrum resistance. As a result, many Gram-negative bacilli possess a complicated set of genes encoding efflux pumps, alterations in outer membrane lipopolysaccharides, regulation of porins and drug inactivating enzymes such as beta-lactamases, that diminish the clinical utility of today's antibiotics. The cross-species mobility of these resistance genes indicates that multidrug resistance will only increase in the future, impacting the efficacy of existing antimicrobials. This trend toward greater resistance comes at a time when very few new antibiotics have been identified capable of controlling such multi-antibiotic resistant pathogens. The continued dissemination of these resistance genes underscores the need for new classes of antibiotics that do not possess the liability of cross-resistance to existing classes of drugs and thereby having diminished potency against Gram-negative bacilli.
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Affiliation(s)
- Thomas D Gootz
- Pfizer Global Research and Development, Department of Antibiotics, Immunology and Cancer, MS 220-2301, Eastern Point Road, Groton, CT 06340, USA.
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Shin KS, Han K, Lee J, Hong SB, Son BR, Youn SJ, Kim J, Shin HS. Imipenem-resistant Achromobacter xylosoxidans carrying blaVIM-2-containing class 1 integron. Diagn Microbiol Infect Dis 2005; 53:215-20. [PMID: 16260111 DOI: 10.1016/j.diagmicrobio.2005.06.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2005] [Accepted: 06/29/2005] [Indexed: 11/30/2022]
Abstract
We characterized seven isolates of imipenem-resistant Achromobacter xylosoxidans that were isolated from patients hospitalized in the intensive care unit at a tertiary hospital in Korea during 2001 to 2003. From the analysis with an isoelectric focusing, polymerase chain reaction, and sequencing methods, all isolates were found to produce VIM-2, OXA-30, and chromosomal AmpC beta-lactamase with a pI of 8.4. They showed a similar antibiogram, which were resistant to all tested aminoglycosides as well as beta-lactams including imipenem (16-32 mg/L) and aztreonam (128 mg/L), and a same DNA fingerprinting pattern by random amplified polymorphic DNA analysis, suggesting that these originated from a single clone. From the analysis of integron structure carried by an isolate of A. xylosoxidans CBU1760, bla(VIM-2) was found to be part of a gene cassette carried on a class 1 integron (3.4 kb) containing three aacA4 gene cassettes. This is the first report of bla(VIM-2) in A. xylosoxidans.
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Affiliation(s)
- Kyeong Seob Shin
- Department of Laboratory Medicine, College of Medicine, Chungbuk National University, Cheongju, 361-711 Republic of Korea.
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29
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Sunde M. Class I integron with a group II intron detected in an Escherichia coli strain from a free-range reindeer. Antimicrob Agents Chemother 2005; 49:2512-4. [PMID: 15917559 PMCID: PMC1140521 DOI: 10.1128/aac.49.6.2512-2514.2005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An Escherichia coli strain, isolated from wild reindeer in a remote mountain area, contained a class 1 integron with two unusual features: a group II intron and a cassette with homology to a superintegron cassette. Alignments indicate that attC sites of gene cassettes may be insertion sites for introns.
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Affiliation(s)
- Marianne Sunde
- Section of Bacteriology, National Veterinary Institute, P.O. Box 8156 Dep, N-0033 Oslo, Norway.
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30
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Quinteira S, Ferreira H, Peixe L. First isolation of blaVIM-2 in an environmental isolate of Pseudomonas pseudoalcaligenes. Antimicrob Agents Chemother 2005; 49:2140-1. [PMID: 15855549 PMCID: PMC1087648 DOI: 10.1128/aac.49.5.2140-2141.2005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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31
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Walsh TR, Toleman MA, Poirel L, Nordmann P. Metallo-beta-lactamases: the quiet before the storm? Clin Microbiol Rev 2005; 18:306-25. [PMID: 15831827 PMCID: PMC1082798 DOI: 10.1128/cmr.18.2.306-325.2005] [Citation(s) in RCA: 999] [Impact Index Per Article: 52.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The ascendancy of metallo-beta-lactamases within the clinical sector, while not ubiquitous, has nonetheless been dramatic; some reports indicate that nearly 30% of imipenem-resistant Pseudomonas aeruginosa strains possess a metallo-beta-lactamase. Acquisition of a metallo-beta-lactamase gene will invariably mediate broad-spectrum beta-lactam resistance in P. aeruginosa, but the level of in vitro resistance in Acinetobacter spp. and Enterobacteriaceae is less dependable. Their clinical significance is further embellished by their ability to hydrolyze all beta-lactams and by the fact that there is currently no clinical inhibitor, nor is there likely to be for the foreseeable future. The genes encoding metallo-beta-lactamases are often procured by class 1 (sometimes class 3) integrons, which, in turn, are embedded in transposons, resulting in a highly transmissible genetic apparatus. Moreover, other gene cassettes within the integrons often confer resistance to aminoglycosides, precluding their use as an alternative treatment. Thus far, the metallo-beta-lactamases encoded on transferable genes include IMP, VIM, SPM, and GIM and have been reported from 28 countries. Their rapid dissemination is worrisome and necessitates the implementation of not just surveillance studies but also metallo-beta-lactamase inhibitor studies securing the longevity of important anti-infectives.
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Affiliation(s)
- Timothy R Walsh
- Department of Pathology and Microbiology, School of Medical Sciences, University of Bristol, Bristol BS8 1TD, United Kingdom.
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32
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Giakkoupi P, Tzouvelekis LS, Daikos GL, Miriagou V, Petrikkos G, Legakis NJ, Vatopoulos AC. Discrepancies and interpretation problems in susceptibility testing of VIM-1-producing Klebsiella pneumoniae isolates. J Clin Microbiol 2005; 43:494-6. [PMID: 15635025 PMCID: PMC540174 DOI: 10.1128/jcm.43.1.494-496.2005] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Susceptibilities to beta-lactam antibiotics of five VIM-1-producing Klebsiella pneumoniae isolates were determined by broth microdilution, Etest, disk diffusion, and the automated systems Vitek 2, Phoenix, and MicroScan. Significant discrepancies were observed in the determination of susceptibility to imipenem and meropenem. Interpretation problems by the automated systems were also noted.
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Affiliation(s)
- P Giakkoupi
- Department of Microbiology, National School of Public Health, 196 Alexandras Ave., Athens 11521, Greece
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Tsou MF, Yu WL, Hung SW, Chi CJ, Chen SC, Wu LT. Detection of cefotaxime-resistant CTX-M-3 in clinical isolates of Serratia marcescens. Folia Microbiol (Praha) 2004; 49:452-6. [PMID: 15530012 DOI: 10.1007/bf02931608] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Strains of Serratia marcescens (isolated in a hospital during April and August 2000) resistant to ampicillin, chloramphenicol, trimethoprim-sulfamethoxazole, streptomycin, tetracycline, and gentamicin were characterized. Out of a total of 34 clinical isolates 6 (17.6 %) exhibited the extended spectrum beta-lactamases (ESBL) resistance; they were also resistant to cefotaxime (minimum inhibitory concentration, MIC > or = 128 microg/mL) but susceptible to imipenem (MIC < or = 0.5 microg/mL). This multidrug resistance was shown to be transferred by a conjugative plasmid. Transconjugants revealed similar MIC profiles when compared to the parental strains. Isoelectric focusing revealed one major transferable beta-lactamase (pI 8.4) which was further identified as CTX-M-3 by PCR and gene sequencing. The presence of strains with this type of ESBL showed the evolution of bla genes and their dissemination among at least three species of the family Enterobacteriaceae isolated within a single hospital. The predominance of CTX-M type enzymes found in this area of Taiwan appeared to be similar to that described in Poland.
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Affiliation(s)
- Mei-Fen Tsou
- Department of Clinical Laboratory, China Medical University Hospital, Taichung, Taiwan, Republic of China
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Galani I, Souli M, Chryssouli Z, Katsala D, Giamarellou H. First identification of an Escherichia coli clinical isolate producing both metallo-beta-lactamase VIM-2 and extended-spectrum beta-lactamase IBC-1. Clin Microbiol Infect 2004; 10:757-60. [PMID: 15301681 DOI: 10.1111/j.1469-0691.2004.00913.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An Escherichia coli strain with decreased susceptibility to carbapenems was isolated from a hospitalised patient in Athens, Greece. The strain was resistant to all beta-lactams, including aztreonam, whereas the MIC of imipenem and meropenem was 0.5 mg/L. A positive EDTA-disk synergy test suggested the production of a metallo-beta-lactamase. PCR experiments revealed the presence of the bla(VIM-2), bla(IBC-1), and bla(TEM-1) genes. Resistance to beta-lactams was not transferable by conjugation. This is the first report of a clinical isolate of E. coli producing VIM-2, and the first report of the coexistence of bla(VIM-2) and bla(IBC-1) in a single clinical isolate.
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Affiliation(s)
- I Galani
- 4th Department of Internal Medicine, Molecular Biology Section, University of Athens Medical School, Athens, Greece
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Lee K, Ha GY, Shin BM, Kim JJ, Kang JO, Jang SJ, Yong D, Chong Y. Metallo-β-lactamase-producing Gram-negative bacilli in Korean Nationwide Surveillance of Antimicrobial Resistance group hospitals in 2003: Continued prevalence of VIM-producing pseudomonas spp. and increase of IMP-producing Acinetobacter spp. Diagn Microbiol Infect Dis 2004; 50:51-8. [PMID: 15380278 DOI: 10.1016/j.diagmicrobio.2004.05.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2004] [Accepted: 05/10/2004] [Indexed: 10/26/2022]
Abstract
Metallo-beta-lactamase (MBL)-producing Pseudomonas spp. and Acinetobacter spp. were prevalent in Korean hospitals. In this study, the prevalence and presence of MBL-producing isolates among imipenem-nonsusceptible and imipenem-susceptible isolates, respectively, were screened. The genetic and phenotypic characteristics of MBL-producing isolates were determined. Among imipenem-nonsusceptible isolates, 52 (11.1%) of 467 Pseudomonas spp. were blaVIM-like allele-positive, and 33 (15.1%) of 218 Acinetobacter spp. were either blaVIM- or blaIMP-like allele-positive. One blaVIM-like allele-positive isolate of Acinetobacter spp. was detected among 84 imipenem-susceptible Acinetobacter isolates. The minimum inhibitory concentration for 90% of isolates of imipenem was higher (>128 microg/mL) for Pseudomonas spp. than Acinetobacter spp. (16 microg/mL), although both had blaVIM-like allele. The source of MBL-producing isolates was mostly the sputum and urine of patients in the intensive care unit. Pulsed-field gel electrophoresis analysis suggested the intra- and inter-hospital spread of MBL-producing strains at some hospitals. In conclusion, blaVIM-like allele-positive P. aeruginosa remained highly prevalent, and the proportion of blaIMP-like allele-positive Acinetobacter spp. has increased significantly in most Korean hospitals.
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Affiliation(s)
- Kyungwon Lee
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, South Korea
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36
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Wu LT, Tsou MF, Wu HJ, Chen HE, Chuang YC, Yu WL. Survey of CTX-M-3 extended-spectrum beta-lactamase (ESBL) among cefotaxime-resistant Serratia marcescens at a medical center in middle Taiwan. Diagn Microbiol Infect Dis 2004; 49:125-9. [PMID: 15183862 DOI: 10.1016/j.diagmicrobio.2004.02.004] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2003] [Accepted: 02/10/2004] [Indexed: 10/26/2022]
Abstract
Thirty-four clinical isolates of Serratia marcescens nonsusceptible to cefotaxime were collected from a medical center in middle Taiwan. Confirmatory tests for extended-spectrum beta-lactamases (ESBLs) by cefotaxime and ceftazidime +/- clavulanic acid using Etest ESBL Screen identified only one ESBL producer; the remaining 33 isolates revealed nondeterminable results, because of off-scale minimum inhibitory concentration (MIC) levels for cefotaxime +/- clavulanic acid. Agar microdilution method using broader MIC ranges confirmed 21 ESBL-producers and one non-determinable result, achieving a highly predicting value compared to golden standard by PCR and DNA sequencing analysis, which identified 22 (65%) isolates containing blaCTX-M-3 genes. Only one strain carried concurrent CTX-M-3 and SHV-5 conferring high-level MICs to both cefotaxime (128 microg/mL) and ceftazidime (64 microg/mL). Other enzymatic mechanisms, such as chromosome-encoded AmpC including a novel SRT-2 enzyme, may confer resistance to cefotaxime on the remaining 12 isolates without ESBL bla genes. Thus, it is unreliable to predict the resistance mechanism by antibiogram, and current Etest ESBL Screen tests. Our study highlights expanding efforts to detect ESBLs in S. marcescens are urgently needed in Taiwan.
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Affiliation(s)
- Lii-Tzu Wu
- Department of Microbiology, Institute of Medical Science, China Medical University, Taichung City, Taiwan
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Abstract
Integrons are genetic elements composed of a gene encoding an integrase, gene cassettes and an integration site for the gene cassettes (att). The integrase excises and integrates the gene cassettes from and into the integron, but integrons themselves are not mobile. Two groups of integrons are known: resistance integrons and super-integrons. Nearly all known gene cassettes from resistance integrons encode resistance to antibiotics or disinfectants. These integrons are found on transposons, plasmids and the bacterial chromosome. Gene cassettes in super-integrons encode a variety of different functions. Super-integrons are located on the bacterial chromosome. More than 100 gene cassettes may be present, in contrast to resistance integrons where less than ten cassettes are present. Many species harbour super-integrons, which are species-specific, whereas particular resistance integrons can be found in a variety of species. The gene cassettes in resistance integrons probably originated from super-integrons. In the last few years, a variety of new gene cassettes have been described. Many of these encode resistance against newer antibiotics such as cephalosporins and carbapenems. Resistance integrons have been found in isolates from a wide variety of sources, including food.
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Affiliation(s)
- A C Fluit
- Eijkman-Winkler Center, P.O. Box 85500, 3508 GA Utrecht, The Netherlands.
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Scoulica EV, Neonakis IK, Gikas AI, Tselentis YJ. Spread of bla(VIM-1)-producing E. coli in a university hospital in Greece. Genetic analysis of the integron carrying the bla(VIM-1) metallo-beta-lactamase gene. Diagn Microbiol Infect Dis 2004; 48:167-72. [PMID: 15023424 DOI: 10.1016/j.diagmicrobio.2003.09.012] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2003] [Accepted: 08/29/2003] [Indexed: 12/20/2022]
Abstract
Bla(VIM-1) gene was detected in four Escherichia coli clinical isolates with both reduced susceptibility to carbapenems and an ESBL phenotype. The VIM-1 determinant was located within the variable region of a Class I integron along with a 6'-N-aminoglycoside acetyltransferase gene (aac(6')-Ib) and it could be transferred by conjugation. In all four clinical isolates the VIM-1 gene cassette presented a characteristic duplication of the 3' end coding 153 nucleotides followed by the first 14 nucleotides of the 59 base element (59be) that however did not seem to affect either the integrity of the coding sequence or the 59be of the gene cassette. These clinical isolates not only harbored the same Class I integron, but they also shared the same discrete ribotype-pattern, indicative for their clonal origin. Spread of carbapenem resistance genes among Enterobacteriaceae in hospital is a matter of great concern.
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Affiliation(s)
- Efstathia V Scoulica
- Department of Clinical Bacteriology, Parasitology, Zoonoses and Geographical Medicine, Faculty of Medicine, University of Crete, Heraklion, Greece.
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39
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Mendes RE, Castanheira M, Garcia P, Guzman M, Toleman MA, Walsh TR, Jones RN. First isolation of bla(VIM-2) in Latin America: report from the SENTRY Antimicrobial Surveillance Program. Antimicrob Agents Chemother 2004; 48:1433-4. [PMID: 15047562 PMCID: PMC375339 DOI: 10.1128/aac.48.4.1433-1434.2004] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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40
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Luzzaro F, Docquier JD, Colinon C, Endimiani A, Lombardi G, Amicosante G, Rossolini GM, Toniolo A. Emergence in Klebsiella pneumoniae and Enterobacter cloacae clinical isolates of the VIM-4 metallo-beta-lactamase encoded by a conjugative plasmid. Antimicrob Agents Chemother 2004; 48:648-50. [PMID: 14742229 PMCID: PMC321512 DOI: 10.1128/aac.48.2.648-650.2004] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Resistance to carbapenems is an emerging problem among gram-negative hospital pathogens. A transferable plasmid encoding the VIM-4 metallo-beta-lactamase was detected in isolates of Klebsiella pneumoniae and Enterobacter cloacae obtained from a single patient under carbapenem therapy. Thus, enterobacteria appear to increasingly contribute to the spread of VIM-type enzymes.
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Affiliation(s)
- Francesco Luzzaro
- Laboratorio di Microbiologia, Ospedale di Circolo, and Università dell'Insubria, I-21100 Varese, Italy
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41
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Toleman MA, Rolston K, Jones RN, Walsh TR. blaVIM-7, an evolutionarily distinct metallo-beta-lactamase gene in a Pseudomonas aeruginosa isolate from the United States. Antimicrob Agents Chemother 2004; 48:329-32. [PMID: 14693560 PMCID: PMC310168 DOI: 10.1128/aac.48.1.329-332.2004] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
As part of the CANCER Antimicrobial Surveillance Program in North America, a Pseudomonas aeruginosa isolate, strain 07-406, was shown to possess a metallo-beta-lactamase, designated VIM-7. bla(VIM-7) is located on a 24-kb plasmid which can be readily transferred into Enterobacteriaceae and other pseudomonads. This is the first report of a mobile metallo-beta-lactamase gene, bla(VIM-7), being detected within the United States.
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Affiliation(s)
- Mark A Toleman
- Department of Pathology and Microbiology, University of Bristol, Bristol BS8 1TD, United Kingdom.
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42
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Lee K, Jang SJ, Lee HJ, Ryoo N, Kim M, Hong SG, Chong Y. Increasing prevalence of vancomycin-resistant Enterococcus faecium, expanded-spectrum cephalosporin-resistant Klebsiella pneumoniae, and imipenem-resistant Pseudomonas aeruginosa in Korea: KONSAR study in 2001. J Korean Med Sci 2004; 19:8-14. [PMID: 14966334 PMCID: PMC2822269 DOI: 10.3346/jkms.2004.19.1.8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The 5th year KONSAR surveillance in 2001 was based on routine test data at 30 participating hospitals. It was of particular interest to find a trend in the resistances of enterococci to vancomycin, of Enterobacteriaceae to the 3rd generation cephalosporin and fluoroquinolone, and of Pseudomonas aeruginosa and acinetobacters to carbapenem. Resistance rates of Gram-positive cocci were: 70% of Staphylococcus aureus to oxacillin; 88% and 16% of Enterococcus faecium to ampicillin and vancomycin, respectively. Seventy-two percent of pneumococci were nonsusceptible to penicillin. The resistance rates of Enterobacteriaceae were: Escherichia coli, 28% to fluoroquinolone; Klebsiella pneumoniae, 27% to ceftazidime, and 20% to cefoxitin; and Enterobacter cloacae, > or =40% to cefotaxime and ceftazidime. The resistance rates of P. aeruginosa were 21% to ceftazidime, 17% to imipenem, and those of the acinetobacters were > or =61% to ceftazidime, aminoglycosides, fluoroquinolone and cotrimoxazole. Thirty-five percent of non-typhoidal salmonellae were ampicillin resistant, and 66% of Haemophilus influenzae were beta-lactamase producers. Notable changes over the 1997-2001 period were: increases in vancomycin-resistant E. faecium, and amikacin- and fluoroquinolone-resistant acinetobacters. With the increasing prevalence of resistant bacteria, nationwide surveillance has become more important for optimal patient management, for the control of nosocomial infection, and for the conservation of the newer antimicrobial agents.
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Affiliation(s)
- Kyungwon Lee
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, Korea
| | - Sook-Jin Jang
- Department of Laboratory Medicine, College of Medicine, Chosun University, Gwangju, Korea
| | - Hee Joo Lee
- Department of Laboratory Medicine, Kyung Hee University Hospital, Seoul, Korea
| | - Namhee Ryoo
- Department of Laboratory Medicine, Keimyung University Dongsan Medical Center, Daegu, Korea
| | - Myungshin Kim
- Department of Laboratory Medicine, College of Medicine, The Catholic University of Korea, Seoul, Korea
| | - Seong Geun Hong
- Department of Laboratory Medicine, Pundang CHA General Hospital, Pochon CHA University, Sungnam, Korea
| | - Yunsop Chong
- Department of Laboratory Medicine, Yonsei University College of Medicine, Seoul, Korea
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43
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Giakkoupi P, Xanthaki A, Kanelopoulou M, Vlahaki A, Miriagou V, Kontou S, Papafraggas E, Malamou-Lada H, Tzouvelekis LS, Legakis NJ, Vatopoulos AC. VIM-1 Metallo-beta-lactamase-producing Klebsiella pneumoniae strains in Greek hospitals. J Clin Microbiol 2003; 41:3893-6. [PMID: 12904412 PMCID: PMC179807 DOI: 10.1128/jcm.41.8.3893-3896.2003] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Seventeen Klebsiella pneumoniae clinical isolates carrying the bla(VIM-1) metallo-beta-lactamase gene were collected in the intensive care units of three hospitals in Athens, Greece, in 2002. They exhibited various carbapenem resistance levels (Etest MICs of imipenem ranged from 4 to 32 microg/ml). All isolates gave positive results by the imipenem-EDTA synergy Etest. The isolates were classified into four main types by pulsed-field gel electrophoresis; the majority of the isolates (5 and 10 isolates) belonged to two types. The bla(VIM-1) gene cassette was part of the variable region of a class 1 integron that also included aac6, dhfrI, and aadA. This structure was carried by transferable plasmids.
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Affiliation(s)
- P Giakkoupi
- Departments of Hygiene and Epidemiology. Microbiology, Medical School, University of Athens, Athens, Greece
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Cantón R, Coque TM, Baquero F. Multi-resistant Gram-negative bacilli: from epidemics to endemics. Curr Opin Infect Dis 2003; 16:315-25. [PMID: 12861084 DOI: 10.1097/00001432-200308000-00003] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
PURPOSE OF REVIEW Infections due to multi-drug resistant Gram-negative bacilli represent a worrying situation for the management of hospitalized patients. In addition, these bacteria are increasingly involved in epidemics throughout the world. This review focuses on recent data that may help to understand the emergence and dissemination of multi-drug resistant bacilli and the current trend from epidemic to endemic situations. RECENT FINDINGS Well-established clones enhance their resistance phenotype by the acquisition of new resistant genes, via gene capture genetic units (plasmids, transposons or integrons), thus facilitating the co-selective process under different antimicrobial selective pressures and therefore the long-term persistence of organisms in selective environments. Not only resistant bacterial clones are selected, but also their genetic structures carrying resistance genes. Therefore, current epidemiology of multi-drug resistant bacilli is not only focused on bacterial clones but also on any kind of resistance gene capture units. In this scenario a multiclonal population structure of bacterial organisms corresponds to a collection of different strains sharing resistance genes carried by horizontally transferred genetic structures. As different strains tend to prefer different environments, this concept helps understand why the epidemiology of multi-drug resistant Gram-negative bacilli is moving from epidemics to endemics. SUMMARY The emergence and spread of multi-drug resistant bacilli in the nosocomial setting should be understood in terms of a complex interplay of bacterial clonality, resistance genes and genetic structures promoting rapid dissemination of antimicrobial resistance. Intervention strategies in the forthcoming scenario should identify existing epidemic and/or endemic situations involving clonal organisms or resistance genes carried by epidemic gene capture units.
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Affiliation(s)
- Rafael Cantón
- Department of Microbiology, Ramón y Cajal University Hospital, Madrid, Spain.
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Miriagou V, Tzelepi E, Gianneli D, Tzouvelekis LS. Escherichia coli with a self-transferable, multiresistant plasmid coding for metallo-beta-lactamase VIM-1. Antimicrob Agents Chemother 2003; 47:395-7. [PMID: 12499222 PMCID: PMC149029 DOI: 10.1128/aac.47.1.395-397.2003] [Citation(s) in RCA: 111] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An Escherichia coli strain exhibiting decreased susceptibility to carbapenems was isolated from a hospitalized patient in Greece. The strain carried a self-transferable plasmid coding for metallo-beta-lactamase VIM-1. bla(VIM-1), along with aacA7, dhfrI, and aadA, was included as a gene cassette in a novel class 1 integron. A Citrobacter freundii ampC-derived gene, not associated with the integron, was also located in the same plasmid.
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Affiliation(s)
- Vivi Miriagou
- Laboratory of Bacteriology, Hellenic Pasteur Institute, Athens, Greece.
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Masika PJ, Afolayan AJ. Antimicrobial activity of some plants used for the treatment of livestock disease in the Eastern Cape, South Africa. JOURNAL OF ETHNOPHARMACOLOGY 2002; 83:129-134. [PMID: 12413718 DOI: 10.1016/s0378-8741(02)00242-8] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Approximately 75% of rural livestock owners in the Eastern Cape province of South Africa use plants or plant based remedies to treat their livestock. Prominent among these plants are Combretum caffrum, Salix capensis and Schotia latifolia. Water, methanolic and acetonic extracts as well as decoctions of the three plants were screened against ten bacteria and five fungi. The results of the antibacterial assay indicated significant activity against all the Gram-positive bacteria tested with the minimum inhibitory concentrations ranging from 0.1 to 5.0 mg/ml. A few of the extracts showed minimal activity, but the majority of extracts were not active on the Gram-negative bacteria. Generally, all the extracts showed some antifungal activity against the five test fungi. Methanolic extracts exhibited higher fungal growth inhibition, whereas the water extracts showed the least inhibition. It was noteworthy that some water extracts promoted fungal growth.
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Affiliation(s)
- P J Masika
- ARDRI, University of Fort Hare, P/Bag X 1314, 5700, Alice, South Africa
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