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Jiang M, Mu Y, Li N, Zhang Z, Han S. Carbapenem-resistant Acinetobacter baumannii from Air and Patients of Intensive Care Units. Pol J Microbiol 2019; 67:333-338. [PMID: 30451450 PMCID: PMC7256820 DOI: 10.21307/pjm-2018-040] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/07/2018] [Indexed: 12/03/2022] Open
Abstract
To understand the molecular epidemiology and antibiotic resistance of air and clinical isolates of Acinetobacter baumannii, the intensive care unit settings of a hospital in Northern China were surveyed in 2014. Twenty non-duplicate A. baumannii isolates were obtained from patients and five isolates of airborne A. baumannii were obtained from the wards’ corridors. Pulsed field gel electrophoresis (PFGE) and multilocus sequence typing (MLST) were used to analyze the homology relationships of isolates. Resistance and resistance genes were detected by drug susceptibility test and PCR. The results demonstrated that all isolates can be classified into eight PFGE types and four sequence types (ST208, ST195, ST369 and ST530). A pair of isolates from patients (TAaba004) and from the air (TAaba012) that share 100% similarity in PFGE was identified, indicating that air might be a potential and important transmission route for A. baumannii. More than 80% of the isolates were resistant to carbapenems and aminoglycoside antibiotics. Twenty-four isolates, which were resistant to carbapenems, carried the blaOXA-23-like gene. The data indicated that air might be an alternative way for the transmission of A. baumannii. Hospitals should pay more attention to this route, and design new measures accordingly.
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Affiliation(s)
- Meijie Jiang
- Laboratory Medicine, Tai'an City Central Hospital, Tai'an, Shandong, China
| | - Yunqing Mu
- Laboratory Medicine, Dezhou City People's Hospital, Dezhou, Shandong, China
| | - Ning Li
- College of Veterinary Medicine, Shandong Agricultural University, Tai'an, Shandong, China
| | - Zhijun Zhang
- Laboratory Medicine, Tai'an City Central Hospital, Tai'an, Shandong, China
| | - Shulin Han
- Department of Public Health, Tai'an City Central Hospital, Tai'an, Shandong, China
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Efficient Synthesis and Antibacterial Evaluation of (±)-Yanglingmycin and Its Analogues. Molecules 2016; 21:96. [PMID: 26784161 PMCID: PMC6273348 DOI: 10.3390/molecules21010096] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 12/30/2015] [Accepted: 01/12/2016] [Indexed: 12/31/2022] Open
Abstract
An efficient synthetic route was developed for the large-scale preparation of (±)-Yanglingmycin and its analogues. Three series of derivatives of (±)-Yanglingmycin were synthesized and the structures of all compounds were elucidated by analyses of NMR and ESI-MS spectra data. Moreover, their antibacterial activities against seven species of bacteria were systematically evaluated by the micro-broth dilution method, most of which displayed considerable activity. It was worth noting that compounds 5b, 5c, 5d, 6g, and 7 were found to be the most promising leading candidates, with peak MIC values of 0.98 μg·mL−1 for Bacillus subtilis, which is superior to positive controls (MIC = 3.91 μg·mL−1). The above results might lay the firm foundation for the design and synthesis of novel antibacterial drugs based on (±)-Yanglingmycin.
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Townsend J, Park AN, Gander R, Orr K, Arocha D, Zhang S, Greenberg DE. Acinetobacter infections and outcomes at an academic medical center: a disease of long-term care. Open Forum Infect Dis 2015; 2:ofv023. [PMID: 26034772 PMCID: PMC4438902 DOI: 10.1093/ofid/ofv023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Accepted: 02/12/2015] [Indexed: 11/14/2022] Open
Abstract
Background. Our study aims to describe the epidemiology, microbial resistance patterns, and clinical outcomes of Acinetobacter infections at an academic university hospital. This retrospective study analyzed all inpatient clinical isolates of Acinetobacter collected at an academic medical center over 4 years. The data were obtained from an Academic tertiary referral center between January 2008 and December 2011. All consecutive inpatients during the study period who had a clinical culture positive for Acinetobacter were included in the study. Patients without medical records available for review or less than 18 years of age were excluded. Methods. Records were reviewed to determine source of isolation, risk factors for acquisition, drug resistance patterns, and clinical outcomes. Repetitive sequence-based polymerase chain reaction of selected banked isolates was used to determine patterns of clonal spread in and among institutions during periods of higher infection rates. Results. Four hundred eighty-seven clinical isolates of Acinetobacter were found in 212 patients (in 252 admissions). Patients with Acinetobacter infections were frequently admitted from healthcare facilities (HCFs) (59%). One hundred eighty-three of 248 (76%) initial isolates tested were resistant to meropenem. One hundred ninety-eight of 249 (79.5%) initial isolates were multidrug resistant (MDR). Factors associated with mortality included bacteremia (odds ratio [OR] = 1.93, P = .024), concomitant steroid use (OR = 2.87, P < .001), admission from a HCF (OR = 6.34, P = .004), and chronic obstructive pulmonary disease (OR = 3.17, P < .001). Conclusions. Acinetobacter isolates at our institution are frequently MDR and are more common among those who reside in HCFs. Our findings underline the need for new strategies to prevent and treat this pathogen, including stewardship efforts in long-term care settings.
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Affiliation(s)
| | | | | | - Kathleen Orr
- Microbiology Laboratory , Parkland Health and Hospital System
| | - Doramarie Arocha
- Division of Infection Prevention , University Hospital Administration, St. Paul University Hospital
| | - Song Zhang
- Division of Biostatistics, Department of Clinical Sciences , University of Texas Southwestern , Dallas, Texas
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Kim UJ, Kim HK, An JH, Cho SK, Park KH, Jang HC. Update on the Epidemiology, Treatment, and Outcomes of Carbapenem-resistant Acinetobacter infections. Chonnam Med J 2014; 50:37-44. [PMID: 25229014 PMCID: PMC4161759 DOI: 10.4068/cmj.2014.50.2.37] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 07/18/2014] [Accepted: 07/28/2014] [Indexed: 11/12/2022] Open
Abstract
Carbapenem-resistant Acinetobacter species are increasingly recognized as major nosocomial pathogens, especially in patients with critical illnesses or in intensive care. The ability of these organisms to accumulate diverse mechanisms of resistance limits the available therapeutic agents, makes the infection difficult to treat, and is associated with a greater risk of death. In this review, we provide an update on the epidemiology, resistance mechanisms, infection control measures, treatment, and outcomes of carbapenem-resistant Acinetobacter infections.
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Affiliation(s)
- Uh Jin Kim
- Department of Infectious Diseases, Chonnam National University Medical School, Gwangju, Korea
| | - Hee Kyung Kim
- Department of Infectious Diseases, Chonnam National University Medical School, Gwangju, Korea
| | - Joon Hwan An
- Department of Infectious Diseases, Chonnam National University Medical School, Gwangju, Korea
| | - Soo Kyung Cho
- Department of Infectious Diseases, Chonnam National University Medical School, Gwangju, Korea
| | - Kyung-Hwa Park
- Department of Infectious Diseases, Chonnam National University Medical School, Gwangju, Korea
| | - Hee-Chang Jang
- Department of Infectious Diseases, Chonnam National University Medical School, Gwangju, Korea
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Dissemination of multidrug-resistant Acinetobacter baumannii carrying BlaOxA-23 from hospitals in central Taiwan. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2013; 46:419-24. [DOI: 10.1016/j.jmii.2012.08.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2012] [Revised: 06/07/2012] [Accepted: 08/08/2012] [Indexed: 11/19/2022]
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Types and prevalence of carbapenem-resistant Acinetobacter calcoaceticus-Acinetobacter baumannii complex in Northern Taiwan. Antimicrob Agents Chemother 2013; 58:201-4. [PMID: 24145535 DOI: 10.1128/aac.00779-13] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The frequency of the carbapenem-resistant Acinetobacter calcoaceticus-Acinetobacter baumannii (CRACB) complex increases annually in our hospitals. However, the types and prevalence of carbapenemases among isolates still remain unclear. In this study, we identified and collected 672 carbapenem-resistant isolates from a medical center in Northern Taiwan between April and December of 2010. There were 577 genospecies 2 (Acinetobacter baumannii), 79 genospecies 13TU, and 16 genospecies 3 isolates. The isolates had an acquired blaOXA-24-like gene, which was confirmed by sequencing for the encoded OXA-72 carbapenemase, and were often associated with high-level carbapenem resistance. These CRACB complex isolates remained susceptible to colistin (100%). The genotyping of isolates was conducted using pulsed-field gel electrophoresis with ApaI digestion. In most clonally related groups, patients were from both branch hospitals. The results indicate that interhospital dissemination of clones occurred. This study provides updated data on the types and prevalence of the CRACB complex. In addition, it presents a warning on the emergence and spread of CRACB complex harboring blaOXA-24-like genes in northern Taiwan.
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Gao J, Zhao X, Bao Y, Ma R, Zhou Y, Li X, Chai T, Cai Y. Antibiotic resistance and OXA-type carbapenemases-encoding genes in airborne Acinetobacter baumannii isolated from burn wards. Burns 2013; 40:295-9. [PMID: 23886986 DOI: 10.1016/j.burns.2013.06.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2013] [Revised: 05/30/2013] [Accepted: 06/01/2013] [Indexed: 11/18/2022]
Abstract
The study was conducted to investigate drug resistance, OXA-type carbapenemases-encoding genes and genetic diversity in airborne Acinetobacter baumannii (A. baumannii) in burn wards. Airborne A. baumannii were collected in burn wards and their corridors using Andersen 6-stage air sampler from January to June 2011. The isolates susceptibility to 13 commonly used antibiotics was examined according to the CLSI guidelines; OXA-type carbapenemases-encoding genes and molecular diversity of isolates were analyzed, respectively. A total of 16 non-repetitive A. baumannii were isolated, with 10 strains having a resistance rate of greater than 50% against the 13 antibiotics. The resistance rate against ceftriaxone, cyclophosvnamide, ciprofloxacin, and imipenem was 93.75% (15/16), but no isolate observed to be resistant to cefoperazone/sulbactam. Resistance gene analyses showed that all 16 isolates carried OXA-51, and 15 isolates carried OXA-23 except No.15; but OXA-24 and OXA-58 resistance genes not detected. The isolates were classified into 13 genotypes (A-M) according to repetitive extragenic palindromic sequence PCR (REP-PCR) results and only six isolates had a homology ≥90%. In conclusion, airborne A. baumannii in the burn wards had multidrug resistance and complex molecular diversity, and OXA-23 and OXA-51 were dominant mechanisms for resisting carbapenems.
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Affiliation(s)
- Jing Gao
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, China, Sino-German Cooperative Research Centre for Zoonosis of Animal Origin Shandong Province, Tai'an Shandong, China; Tai'an City Central Hospital, Tai'an, China
| | - Xiaonan Zhao
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, China, Sino-German Cooperative Research Centre for Zoonosis of Animal Origin Shandong Province, Tai'an Shandong, China
| | - Ying Bao
- Tai'an City Central Hospital, Tai'an, China
| | - Ruihua Ma
- Affiliated Hospital of the Shandong Agricultural University, Tai'an, China
| | - Yufa Zhou
- Daiyue Husbandry Bureau of Tai'an, Tai'an, China
| | - Xinxian Li
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, China, Sino-German Cooperative Research Centre for Zoonosis of Animal Origin Shandong Province, Tai'an Shandong, China; Tai'an City Central Hospital, Tai'an, China; Affiliated Hospital of the Shandong Agricultural University, Tai'an, China; Daiyue Husbandry Bureau of Tai'an, Tai'an, China
| | - Tongjie Chai
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, China, Sino-German Cooperative Research Centre for Zoonosis of Animal Origin Shandong Province, Tai'an Shandong, China.
| | - Yumei Cai
- College of Animal Science and Veterinary Medicine, Shandong Agricultural University, China, Sino-German Cooperative Research Centre for Zoonosis of Animal Origin Shandong Province, Tai'an Shandong, China.
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Molecular epidemiology, antimicrobial susceptibility and carbapenemase resistance determinants among Acinetobacter baumannii clinical isolates in Taiwan. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2013; 47:324-32. [PMID: 23726465 DOI: 10.1016/j.jmii.2013.03.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 01/25/2013] [Accepted: 03/27/2013] [Indexed: 11/21/2022]
Abstract
BACKGROUND Emerging carbapenem resistance among Acinetobacter baumannii clinical isolates is a worldwide problem. Infections caused by A. baumannii are increasing and demonstrate high mortality rates. This study aimed to establish a nationwide surveillance of antimicrobial susceptibility, carbapenemase genes, and clonal relationships of A. baumannii clinical isolates in Taiwan. METHODS Clinical isolates of Acinetobacter calcoaceticus-A. baumannii (ACB) complex collected by the Taiwan Surveillance of Antimicrobial Resistance-V program between July 2006 and September 2006 were used in this study. Genospecies identification was verified by 16S-23S rRNA intergenic-spacer sequences. Carbapenemase genes were detected by polymerase chain reaction. Pulsed-field gel electrophoresis and multilocus sequence typing (MLST) was applied for identification of clonal relationships. RESULTS Among the 151 ACB-complex isolates collected, 134 (88.7%) were A. baumannii, 12 (8.0%) were A. pittii, and five (3.3%) were A. nosocomialis. A. baumannii isolates showed higher resistance rates to ciprofloxacin, amikacin, and ampicillin/sulbactam than A. pittii or A. nosocomialis (all p < 0.001). The most commonly detected carbapenemase genes were bla(OxA-51) (n = 135), followed by bla(OxA-24) (n = 4), bla(OxA-23) (n = 2), and bla(OxA-58) (n = 1). Three major A. baumannii clones were found throughout Taiwan, and showed significantly higher resistance rates to ciprofloxacin, amikacin, and ampicillin/sulbactam than the other A. baumannii isolates (100% vs. 68.7%, p < 0.001; 98.4% vs. 61.5%, p < 0.001; and 66.7% vs. 39.8%, p = 0.004; respectively). MLST showed that these major clones were sequence type 2 and belonged to international clonal complex 2. CONCLUSION Our results demonstrate clonal spreading of A. baumannii in Taiwan hospitals and that these clones were more resistant to many antimicrobial agents. Efforts to prevent and control A. baumannii colonization/infections and prudent use of antibiotics to reduce antimicrobial selective pressure should be emphasized.
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Multidrug-resistant Acinetobacter baumannii outbreak: an investigation of the possible routes of transmission. Public Health 2013; 127:386-91. [DOI: 10.1016/j.puhe.2013.01.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Revised: 10/22/2012] [Accepted: 01/29/2013] [Indexed: 11/18/2022]
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Molecular surveillance and clinical outcomes of carbapenem-resistant Escherichia coli and Klebsiella pneumoniae infections. JOURNAL OF MICROBIOLOGY, IMMUNOLOGY, AND INFECTION = WEI MIAN YU GAN RAN ZA ZHI 2012. [PMID: 23200553 DOI: 10.1016/j.jmii.2012.08.029] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND/PURPOSE The emergence of carbapenem-resistant Enterobacteriaceae (CRE) is a cause for great concern. The aim of this study was to evaluate antimicrobial susceptibility, mechanisms of carbapenem-resistance in two members of the Enterobacteriaceae family (Escherichia coli and Klebsiella pneumoniae), and clinical outcomes of their infections. METHODS The susceptibility tests of 16 E. coli and 60 K. pneumoniae isolates, collected from 2010 to 2011, were assessed. The minimal inhibitory concentrations of eight antimicrobial agents were assessed by the broth microdilution method according to the recommendations of the Clinical and Laboratory Standards Institute. The detection of beta-lactamase genes was performed by polymerase chain reaction. The genetic relatedness of these isolates was determined by pulsed-field gel electrophoresis (PFGE) fingerprinting. RESULTS The carbapenemase genes blaKPC-2 and blaOxA were detected in one and five K. pneumoniae isolates, respectively. The genetic combinations blaSHV-5-blaDHA and blaSHV-5-blaCTx-M-G9 were prevalent in 45% and 26.7% of 60 K. pneumoniae isolates, respectively. The susceptibility rates of 60 K. pneumoniae isolates to colistin and tigecycline were 58.3% and 50.0%, respectively. The 30-day mortality rates of the patients treated with carbapenem, colistin, or tigecycline were as high as 60.6%. Nine clusters of K. pneumoniae isolates were identified by PFGE fingerprinting. CONCLUSION The findings of carbapenemase genes in a few isolates and small clusters of CRE indicated the emerging problems in the hospital. The high mortality rates were observed in the patients treated by colistin and tigecycline, although they were the only alternative treatment options for CRE infections. Active surveillance and an effective infection control strategy should be implemented to control the spread of CRE infections.
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Ferreira AE, Marchetti DP, Cunha GRD, Oliveira LMD, Fuentefria DB, Dall Bello AG, Barth AL, Corção G. Molecular characterization of clinical multiresistant isolates of Acinetobacter sp. from hospitals in Porto Alegre, State of Rio Grande do Sul, Brazil. Rev Soc Bras Med Trop 2012; 44:725-30. [PMID: 22231246 DOI: 10.1590/s0037-86822011000600014] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 07/29/2011] [Indexed: 11/21/2022] Open
Abstract
INTRODUCTION Hospitals around the world have presented multiresistant Acinetobacter sp. outbreaks. The spread of these isolates that harbor an increasing variety of resistance genes makes the treatment of these infections and their control within the hospital environment more difficult. This study aimed to evaluate the occurrence and dissemination of Acinetobacter sp. multiresistant isolates and to identify acquired resistance genes. METHODS We analyzed 274 clinical isolates of Acinetobacter sp. from five hospitals in Porto Alegre, RS, Brazil. We evaluated the susceptibility to antimicrobial, acquired resistance genes from Ambler's classes B and D, and performed molecular typing of the isolates using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) technique. RESULTS A high (68%) percentage of multiresistant isolates of Acinetobacter sp. was observed, and 69% were resistant to carbapenems. We identified 84% of isolates belonging to species A. baumannii because they presented the gene blaOXA-51. The gene blaOXA-23 was detected in 62% of the isolates, and among these, 98% were resistant to carbapenems. Using the ERIC-PCR technique, we identified clones of Acinetobacter sp. spread among the four hospitals analyzed during the sampling period. CONCLUSIONS The data indicate the dissemination of Acinetobacter sp. isolates among hospitals and their permanence in the hospital after one year.
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Affiliation(s)
- Alessandra Einsfeld Ferreira
- Programa de Pos Graduacao em Microbiologia Agricola e do Ambiente, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brasil
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Chen Z, Liu W, Zhang Y, Li Y, Jian Z, Deng H, Zou M, Liu Y. Molecular epidemiology of carbapenem-resistantAcinetobacterspp. from XiangYa Hospital, in Hunan Province, China. J Basic Microbiol 2012; 53:121-7. [PMID: 22581767 DOI: 10.1002/jobm.201100420] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Accepted: 12/12/2011] [Indexed: 11/08/2022]
Affiliation(s)
- Zhenhua Chen
- Department of Clinical Laboratory; Xiangya Hospital of Central South University; Changsha; China
| | - Wenen Liu
- Department of Clinical Laboratory; Xiangya Hospital of Central South University; Changsha; China
| | - Yunli Zhang
- Department of Clinical Laboratory; Xiangya Hospital of Central South University; Changsha; China
| | - Yanbing Li
- Department of Clinical Laboratory; Xiangya Hospital of Central South University; Changsha; China
| | - Zijuan Jian
- Department of Clinical Laboratory; Xiangya Hospital of Central South University; Changsha; China
| | - Hongli Deng
- Department of Clinical Laboratory; Xiangya Hospital of Central South University; Changsha; China
| | - Mingxiang Zou
- Department of Clinical Laboratory; Xiangya Hospital of Central South University; Changsha; China
| | - Yuanyuan Liu
- Department of Clinical Laboratory; Xiangya Hospital of Central South University; Changsha; China
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Mostachio AK, Levin AS, Rizek C, Rossi F, Zerbini J, Costa SF. High prevalence of OXA-143 and alteration of outer membrane proteins in carbapenem-resistant Acinetobacter spp. isolates in Brazil. Int J Antimicrob Agents 2012; 39:396-401. [PMID: 22455794 DOI: 10.1016/j.ijantimicag.2012.01.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2011] [Revised: 01/02/2012] [Accepted: 01/21/2012] [Indexed: 10/28/2022]
Abstract
Carbapenem resistance amongst Acinetobacter spp. has been increasing in the last decade. This study evaluated the outer membrane protein (OMP) profile and production of carbapenemases in 50 carbapenem-resistant Acinetobacter spp. isolates from bloodstream infections. Isolates were identified by API20NE. Minimum inhibitory concentrations (MICs) for carbapenems were determined by broth microdilution. Carbapenemases were studied by phenotypic tests, detection of their encoding gene by polymerase chain reaction (PCR) amplification, and imipenem hydrolysis. Nucleotide sequencing confirming the enzyme gene type was performed using MegaBACE 1000. The presence of OMPs was studied by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and PCR. Molecular typing was performed using pulsed-field gel electrophoresis (PFGE). All isolates were resistant to carbapenems. Moreover, 98% of the isolates were positive for the gene encoding the enzyme OXA-51-like, 18% were positive for OXA-23-like (only one isolate did not show the presence of the insertion sequence ISAba1 adjacent to this gene) and 76% were positive for OXA-143 enzyme. Five isolates (10%) showed the presence of the IMP-1 gene. Imipenem hydrolysing activity was detected in only three strains containing carbapenemase genes, comprising two isolates containing the bla(IMP) gene and one containing the bla(OXA-51/OXA-23-like) gene. The OMP of 43 kDa was altered in 17 of 25 strains studied, and this alteration was associated with a high meropenem MIC (256 μg/mL) in 5 of 7 strains without 43 kDa OMP. On the other hand, decreased OMP 33-36 kDa was found in five strains. The high prevalence of OXA-143 and alteration of OMPs might have been associated with a high level of carbapenem resistance.
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Affiliation(s)
- Anna Karina Mostachio
- Laboratory of Bacteriology (LIM-54), Hospital das Clínicas, Medical School of the University of São Paulo, São Paulo, Brazil
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Durante-Mangoni E, Zarrilli R. Global spread of drug-resistant Acinetobacter baumannii: molecular epidemiology and management of antimicrobial resistance. Future Microbiol 2011; 6:407-22. [PMID: 21526942 DOI: 10.2217/fmb.11.23] [Citation(s) in RCA: 109] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Acinetobacter baumannii is an opportunistic Gram-negative pathogen with increasing relevance in a variety of hospital-acquired infections especially among intensive care unit patients. Resistance to antimicrobial agents is the main reason for A. baumannii spread. A. baumannii outbreaks described worldwide are caused by a limited number of genotypic clusters of multidrug-resistant strains that successfully spread among hospitals of different cities and countries. In this article, we will focus on the mechanisms responsible for resistance to antimicrobials and disinfectants in A. baumannii and the epidemiology of drug-resistant A. baumannii in healthcare facilities. We will also discuss the therapeutic and infection control strategies for management of drug-resistant A. baumannii epidemics.
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Affiliation(s)
- Emanuele Durante-Mangoni
- Chair of Internal Medicine & Unit of Transplant Medicine, Second University of Naples, Monaldi Hospital, Naples, Italy
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Neonakis IK, Spandidos DA, Petinaki E. Confronting multidrug-resistant Acinetobacter baumannii: a review. Int J Antimicrob Agents 2010; 37:102-9. [PMID: 21130607 DOI: 10.1016/j.ijantimicag.2010.10.014] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Accepted: 10/08/2010] [Indexed: 11/27/2022]
Abstract
Multidrug-resistant Acinetobacter baumannii (MDR-AB) infections are difficult to treat owing to the extremely limited armamentarium. The present review reports all available treatment options against MDR-AB, including single molecules, combination schemes, and alternative modes of antimicrobial administration. Additionally, a group of recently reported peptides with anti-MDR-AB activity is described.
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Affiliation(s)
- Ioannis K Neonakis
- Department of Microbiology, Medical School, University of Thessaly, Larissa, Greece.
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