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Budia-Silva M, Kostyanev T, Ayala-Montaño S, Bravo-Ferrer Acosta J, Garcia-Castillo M, Cantón R, Goossens H, Rodriguez-Baño J, Grundmann H, Reuter S. International and regional spread of carbapenem-resistant Klebsiella pneumoniae in Europe. Nat Commun 2024; 15:5092. [PMID: 38877000 PMCID: PMC11178878 DOI: 10.1038/s41467-024-49349-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Accepted: 05/31/2024] [Indexed: 06/16/2024] Open
Abstract
Carbapenem-resistant Klebsiella pneumoniae (CRKP) are of particular concern due to the spread of antibiotic resistance genes associated with mobile genetic elements. In this study, we collected 687 carbapenem-resistant strains recovered among clinical samples from 41 hospitals in nine Southern European countries (2016-2018). We identified 11 major clonal lineages, with most isolates belonging to the high-risk clones ST258/512, ST101, ST11, and ST307. blaKPC-like was the most prevalent carbapenemase-encoding gene (46%), with blaOXA-48 present in 39% of isolates. Through the combination and comparison of this EURECA collection with the previous EuSCAPE collection (2013-2014), we investigated the spread of high-risk clones circulating in Europe exhibiting regional differences. We particularly found blaKPC-like ST258/512 in Greece, Italy, and Spain, blaOXA-48 ST101 in Serbia and Romania, blaNDM ST11 in Greece, and blaOXA-48-like ST14 in Türkiye. Genomic surveillance across Europe thus provides crucial insights for local risk mapping and informs necessary adaptions for implementation of control strategies.
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Affiliation(s)
- Mabel Budia-Silva
- Institute for Infection Prevention and Control, University of Freiburg - Medical Center, Freiburg, Germany
| | - Tomislav Kostyanev
- Laboratory of Medical Microbiology, University of Antwerp, Antwerp, Belgium
- Research Group for Global Capacity Building, National Food Institute, Technical University of Denmark, Kgs. Lyngby, Denmark
| | - Stefany Ayala-Montaño
- Institute for Infection Prevention and Control, University of Freiburg - Medical Center, Freiburg, Germany
| | - Jose Bravo-Ferrer Acosta
- Unidad Clínica de Enfermedades Infecciosas y Microbiología, Instituto de Biomedicina de Sevilla (IBiS)/CSIC, Hospital Universitario Virgen Macarena; and Departamento de Medicina, Universidad de Sevilla, Seville, Spain
| | - Maria Garcia-Castillo
- Servicio de Microbiología, Hospital Universitario Ramón y Cajal and Instituto Ramón y Caja de Investigación Sanitaria (IRYCIS), Madrid, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Institute de Salud Carlos III, Madrid, Spain
| | - Rafael Cantón
- Servicio de Microbiología, Hospital Universitario Ramón y Cajal and Instituto Ramón y Caja de Investigación Sanitaria (IRYCIS), Madrid, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Institute de Salud Carlos III, Madrid, Spain
| | - Herman Goossens
- Laboratory of Medical Microbiology, University of Antwerp, Antwerp, Belgium
| | - Jesus Rodriguez-Baño
- Unidad Clínica de Enfermedades Infecciosas y Microbiología, Instituto de Biomedicina de Sevilla (IBiS)/CSIC, Hospital Universitario Virgen Macarena; and Departamento de Medicina, Universidad de Sevilla, Seville, Spain
- CIBER de Enfermedades Infecciosas (CIBERINFEC), Institute de Salud Carlos III, Madrid, Spain
| | - Hajo Grundmann
- Institute for Infection Prevention and Control, University of Freiburg - Medical Center, Freiburg, Germany
| | - Sandra Reuter
- Institute for Infection Prevention and Control, University of Freiburg - Medical Center, Freiburg, Germany.
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2
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Kaur JN, Singh N, Smith NM, Klem JF, Cha R, Lang Y, Chen L, Kreiswirth B, Holden PN, Bulitta JB, Tsuji BT. Next generation antibiotic combinations to combat pan-drug resistant Klebsiella pneumoniae. Sci Rep 2024; 14:3148. [PMID: 38326428 PMCID: PMC10850076 DOI: 10.1038/s41598-024-53130-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 01/29/2024] [Indexed: 02/09/2024] Open
Abstract
Antimicrobial resistance has emerged as one of the leading public health threats of the twenty-first century. Gram-negative pathogens have been a major contributor to the declining efficacy of antibiotics through both acquired resistance and tolerance. In this study, a pan-drug resistant (PDR), NDM-1 and CTX-M-15 co-producing isolate of K. pneumoniae, CDC Nevada, (Kp Nevada) was exposed to the clinical combination of aztreonam + ceftazidime/avibactam (ATM/CAZ/AVI) to overcome metallo-β-lactamases. Unexpectedly, the β-lactam combination resulted in long filamentous cell formation induced by PBP3 inhibition over 168 h in the hollow fiber infection model experiments with eventual reversion of the total population upon drug removal. However, the addition of imipenem to the two drug β-lactam combination was highly synergistic with suppression of all drug resistant subpopulations over 5 days. Scanning electron microscopy and fluorescence microscopy for all imipenem combinations in time kill studies suggested a role for imipenem in suppression of long filamentous persisters, via the formation of metabolically active spheroplasts. To complement the imaging studies, salient transcriptomic changes were quantified using RT-PCR and novel cassette assay evaluated β-lactam permeability. This showed significant upregulation of both spheroplast protein Y (SPY), a periplasmic chaperone protein that has been shown to be related to spheroplast formation, and penicillin binding proteins (PBP1, PBP2, PBP3) for all combinations involving imipenem. However, with aztreonam alone, pbp1, pbp3 and spy remained unchanged while pbp2 levels were downregulated by > 25%. Imipenem displayed 207-fold higher permeability as compared with aztreonam (mean permeability coefficient of 17,200 nm/s). Although the clinical combination of aztreonam/avibactam and ceftazidime has been proposed as an important treatment of MBL Gram-negatives, we report the first occurrence of long filamentous persister formation. To our knowledge, this is the first study that defines novel β-lactam combinations involving imipenem via maximal suppression of filamentous persisters to combat PDR CDC Nevada K. pneumoniae.
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Affiliation(s)
- Jan Naseer Kaur
- Center for Infectious Diseases Next Generation Therapeutics, University at Buffalo, Buffalo, NY, USA.
- Division of Clinical and Translational Therapeutics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA.
| | - Navaldeep Singh
- Center for Infectious Diseases Next Generation Therapeutics, University at Buffalo, Buffalo, NY, USA
- Division of Clinical and Translational Therapeutics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Nicholas M Smith
- Center for Infectious Diseases Next Generation Therapeutics, University at Buffalo, Buffalo, NY, USA
- Division of Clinical and Translational Therapeutics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Jack F Klem
- Center for Infectious Diseases Next Generation Therapeutics, University at Buffalo, Buffalo, NY, USA
- Division of Clinical and Translational Therapeutics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Raymond Cha
- Center for Infectious Diseases Next Generation Therapeutics, University at Buffalo, Buffalo, NY, USA
- Division of Clinical and Translational Therapeutics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Yinzhi Lang
- Department of Pharmacotherapy and Translational Research, College of Pharmacy, University of Florida, Orlando, FL, USA
| | - Liang Chen
- Center for Discovery and Innovation, Hackensack Meridian Health, Edison, NJ, USA
| | - Barry Kreiswirth
- Center for Discovery and Innovation, Hackensack Meridian Health, Edison, NJ, USA
| | - Patricia N Holden
- Center for Infectious Diseases Next Generation Therapeutics, University at Buffalo, Buffalo, NY, USA
- Division of Clinical and Translational Therapeutics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA
| | - Jürgen B Bulitta
- Department of Pharmacotherapy and Translational Research, College of Pharmacy, University of Florida, Orlando, FL, USA
| | - Brian T Tsuji
- Center for Infectious Diseases Next Generation Therapeutics, University at Buffalo, Buffalo, NY, USA.
- Division of Clinical and Translational Therapeutics, School of Pharmacy and Pharmaceutical Sciences, University at Buffalo, Buffalo, NY, USA.
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3
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Tofarides AG, Dimitriou P, Nikolopoulos GK, Rogkas D, Flourou C, Khattab E, Kasapi D, Azina C, Christaki E. Factors Associated with Extended-Spectrum β-Lactamases and Carbapenem-Resistant Klebsiella pneumoniae Bloodstream Infections: A Five-Year Retrospective Study. Pathogens 2023; 12:1277. [PMID: 38003742 PMCID: PMC10675166 DOI: 10.3390/pathogens12111277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 10/19/2023] [Accepted: 10/21/2023] [Indexed: 11/26/2023] Open
Abstract
Klebsiella pneumoniae is one of the leading causes of nosocomial infections. It has been estimated that nosocomial infection by Klebsiella pneumoniae comprises 3-8% of all nosocomial infections. Klebsiella pneumoniae bloodstream infections (BSIs) occur worldwide with varying mortality. Resistant strains, like those producing extended-spectrum beta-lactamases (ESBL) and carbapenemases, are becoming increasingly common, especially in hospital settings, posing therapeutic challenges. In this article, we aimed to study the epidemiology and risk factors of BSIs due to resistant Klebsiella pneumoniae strains in the period 1 January 2014-31 December 2018 at the Nicosia General Hospital, the largest tertiary hospital in Cyprus. Data on demographics, co-morbidities, prior hospitalization, prior intensive care unit (ICU) admission, previous antimicrobial use, nosocomial acquisition of the infection, the presence of a prosthetic device or surgery, and the primary site of infection were retrospectively recorded. Associations between the detection of ESBL Klebsiella pneumoniae BSIs and factors/covariates were examined using logistic regression. This study involved 175 patients with BSI caused by Klebsiella pneumoniae. Of these, 61 BSIs were caused by ESBL strains, 101 by non-ESBL, and 13 by carbapenem-resistant (CR) strains. In univariable analyses, age, sex, heart disease, antimicrobial use during current admission, previous hospitalization (ward or ICU), and primary BSI were associated with the presence of an ESBL strain. Antibiotic use during current admission and heart disease remained statistically significantly associated with ESBL Klebsiella pneumoniae BSI in multivariable models. Antibiotic use during current admission, respiratory infection, and a recent history of surgery were more prevalent among CR Klebsiella pneumoniae BSI patients than among non-CR Klebsiella pneumoniae BSI patients. Our study showed that recent antimicrobial use and heart disease were associated with BSI due to ESBL-producing Klebsiella pneumoniae. This finding could inform clinical practice in hospital settings.
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Affiliation(s)
- Andreas G. Tofarides
- Department of Internal Medicine, Nicosia General Hospital, 2029 Nicosia, Cyprus; (P.D.); (C.F.); (E.K.); (D.K.); (C.A.)
- 1st Division of Internal Medicine & Infectious Diseases Unit, University Hospital of Ioannina, Faculty of Medicine, University of Ioannina, 45500 Ioannina, Greece;
| | - Panagiotis Dimitriou
- Department of Internal Medicine, Nicosia General Hospital, 2029 Nicosia, Cyprus; (P.D.); (C.F.); (E.K.); (D.K.); (C.A.)
| | | | - Dimitrios Rogkas
- 1st Division of Internal Medicine & Infectious Diseases Unit, University Hospital of Ioannina, Faculty of Medicine, University of Ioannina, 45500 Ioannina, Greece;
| | - Christina Flourou
- Department of Internal Medicine, Nicosia General Hospital, 2029 Nicosia, Cyprus; (P.D.); (C.F.); (E.K.); (D.K.); (C.A.)
| | - Elina Khattab
- Department of Internal Medicine, Nicosia General Hospital, 2029 Nicosia, Cyprus; (P.D.); (C.F.); (E.K.); (D.K.); (C.A.)
| | - Diamanto Kasapi
- Department of Internal Medicine, Nicosia General Hospital, 2029 Nicosia, Cyprus; (P.D.); (C.F.); (E.K.); (D.K.); (C.A.)
| | - Chara Azina
- Department of Internal Medicine, Nicosia General Hospital, 2029 Nicosia, Cyprus; (P.D.); (C.F.); (E.K.); (D.K.); (C.A.)
| | - Eirini Christaki
- 1st Division of Internal Medicine & Infectious Diseases Unit, University Hospital of Ioannina, Faculty of Medicine, University of Ioannina, 45500 Ioannina, Greece;
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Al-Sheboul SA, Al-Madi GS, Brown B, Hayajneh WA. Prevalence of Extended-Spectrum β-Lactamases in Multidrug-Resistant Klebsiella pneumoniae Isolates in Jordanian Hospitals. J Epidemiol Glob Health 2023; 13:180-190. [PMID: 37095370 PMCID: PMC10272028 DOI: 10.1007/s44197-023-00096-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 03/30/2023] [Indexed: 04/26/2023] Open
Abstract
The increase in the prevalence of infections caused by certain bacteria, such as Klebsiella pneumonia (K. pneumoniae), is a global health concern. Bacterial production of an enzyme called extended-spectrum beta-lactamase (ESBL) can generate resistance to antimicrobial therapeutics. Therefore, between 2012 and 2013, we investigated K. pneumoniae that produce ESBLs with the prevalence of individual genes including blaSHV, blaCTX-M, blaTEM, and blaOXA isolated from clinical samples. A total of 99 variable diagnostic samples including blood from hematological malignancies (n = 14) or other clinical sources including sputum, pus, urine, and wound (n = 85) were analyzed. All samples' bacterial type was confirmed and their susceptibility to antimicrobial agents was established. Polymerase chain reaction (PCR) amplification was carried out to ascertain presence of specific genes that included blaSHV, blaCTX-M, blaTEM, and blaOXA. Plasmid DNA profiles were determined to assess significance between resistance to antimicrobial agents and plasmid number. It was found that among non-hematologic malignancy isolates, the highest rate of resistance was 87.9% to imipenem, with lowest rate being 2% to ampicillin. However, in hematologic malignancy isolates, the highest microbial resistance was 92.9% to ampicillin with the lowest rate of resistance at 28.6% to imipenem. Among collected isolates, 45% were ESBL-producers with 50% occurrence in hematologic malignancy individuals that were ESBL-producers. Within ESBL-producing isolates from hematologic malignancy individuals, blaSHV was detected in 100%, blaCTX-M in 85.7%, and blaTEM and blaOXA-1 at 57.1% and 27.1%, respectively. In addition, blaSHV, blaCTX-M, and blaOXA were found in all non-hematological malignancy individuals with blaTEM detected in 55.5% of samples. Our findings indicate that ESBLs expressing blaSHV and blaCTX-M genes are significantly prevalent in K. pneumoniae isolates from hematologic malignancy individuals. Plasmid analysis indicated plasmids in isolates collected from hematological malignancy individuals. Furthermore, there was a correlation between resistance to antimicrobial agents and plasmids within two groups analyzed. This study indicates an increase in incidence of K. pneumoniae infections displaying ESBL phenotypes in Jordan.
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Affiliation(s)
- Suhaila A. Al-Sheboul
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, Jordan University of Sciences and Technology (JUST), Irbid, Jordan
| | - Ghina S. Al-Madi
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, Jordan University of Sciences and Technology (JUST), Irbid, Jordan
| | | | - Wail A. Hayajneh
- Department of Pediatrics and Neonatology, Faculty of Medicine and King Abdullah University Hospital, Jordan University of Science and Technology (JUST), Irbid, Jordan
- Children’s National Hospital, Saint Louis University, St. Joseph’s University Medical Center, Paterson, USA
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5
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Fodah RA, Scott JB, Warawa JM. Direct monitoring of meropenem therapeutic efficacy against Klebsiella pneumoniae respiratory infection by bioluminescence imaging. J Med Microbiol 2023; 72. [PMID: 37252851 DOI: 10.1099/jmm.0.001686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023] Open
Abstract
Introduction. Klebsiella pneumoniae is a major threat to public health worldwide. It is the causative agent for multiple disease presentations including urinary tract infection, septicemia, liver abscess, wound infection and respiratory tract infection. K. pneumoniae causes community- and hospital-acquired pneumonia, which is a devastating disease associated with high mortality rates.Hypothesis. There is a growing concern about the emergence of multidrug-resistant K. pneumoniae strains complicating the treatment with the current available therapeutics; therefore, there is an urgent need for the development of new antimicrobial agents.Aim. K. pneumoniae causes an acute respiratory disease in mice and in the current work we investigated the capability to perform non-invasive monitoring of bioluminescent Klebsiella to monitor therapeutic efficacy.Methodology. We engineered a bioluminescence reporter strain of K. pneumoniae to monitor the impact of antibiotics in a murine respiratory disease model.Results. We demonstrate that bioluminescence correlates with bacterial numbers in host tissues allowing for a non-invasive enumeration of bacterial replication in vivo. Light production is directly linked to bacterial viability, and this novel bioluminescent K. pneumoniae strain enabled monitoring of the efficacy of meropenem therapy in arresting bacterial proliferation in the lung.Conclusion. The use of non-invasive bioluminescent imaging improves preclinical animal model testing to detect study outcome earlier and with higher sensitivity.
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Affiliation(s)
- Ramy A Fodah
- Department of Microbiology and Immunology, University of Louisville, Louisville, USA
- King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
- Present address: King Saud bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
| | - Jacob B Scott
- Dental School, University of Louisville, Louisville, Kentucky, USA
| | - Jonathan M Warawa
- Department of Microbiology and Immunology, University of Louisville, Louisville, USA
- Center for Predictive Medicine, University of Louisville, Louisville, USA
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Luo H, Hang Y, Zhu H, Zhong Q, Peng S, Gu S, Fang X, Hu L. Rapid Identification of Carbapenemase-Producing Klebsiella pneumoniae Using Headspace Solid-Phase Microextraction Combined with Gas Chromatography-Mass Spectrometry. Infect Drug Resist 2023; 16:2601-2609. [PMID: 37152404 PMCID: PMC10162101 DOI: 10.2147/idr.s404742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 04/14/2023] [Indexed: 05/09/2023] Open
Abstract
Background Carbapenemase-producing Klebsiella pneumoniae is an unprecedented threat to public health, and its detection remains challenging. Analysis of microbial volatile organic compounds (VOCs) may offer a rapid way to determine bacterial antibiotic susceptibility. Purpose The aim of this study was to explore the VOCs released by carbapenemase-producing carbapenem-resistant Klebsiella pneumoniae (CRKP) using headspace solid-phase microextraction/gas chromatography-mass spectrometry (HS-SPME/GC-MS). Methods Test bacteria were incubated in trypticase soy broth to the end of exponential growth phase, and imipenem was added in the middle time. Headspace VOCs were concentrated and analyzed using HS-SPME/GC-MS. Results The compound 3-methyl-1-butanol was found to be a biomarker among the 26 bacterial isolates (10 KPC-positive, 10 NDM-positive, 2 IMP-positive, 2 carbapenemase-negative CRKP, and 2 carbapenem-susceptible K. pneumonoiae). Conclusion This study explored a promising new strategy for the screening of carbapenemase-producing CRKP strains. Further research with larger sample sizes will potentially accelerate the application of biomarkers in routine microbiology.
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Affiliation(s)
- Hong Luo
- Jiangxi Provincial Key Laboratory of Medicine, Clinical Laboratory of the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China
| | - Yaping Hang
- Jiangxi Provincial Key Laboratory of Medicine, Clinical Laboratory of the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China
| | - Hongying Zhu
- Clinical Laboratory of Ganzhou People’s Hospital, Ganzhou, Jiangxi, People’s Republic of China
| | - Qiaoshi Zhong
- Jiangxi Provincial Key Laboratory of Medicine, Clinical Laboratory of the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China
| | - Suqin Peng
- Jiangxi Provincial Key Laboratory of Medicine, Clinical Laboratory of the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China
| | - Shumin Gu
- Jiangxi Provincial Key Laboratory of Medicine, Clinical Laboratory of the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China
| | - Xueyao Fang
- Jiangxi Provincial Key Laboratory of Medicine, Clinical Laboratory of the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China
| | - Longhua Hu
- Jiangxi Provincial Key Laboratory of Medicine, Clinical Laboratory of the Second Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People’s Republic of China
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Yang Y, He R, Wu Y, Qin M, Chen J, Feng Y, Zhao R, Xu L, Guo X, Tian GB, Dai M, Yan B, Qin LN. Characterization of two multidrug-resistant Klebsiella pneumoniae harboring tigecycline-resistant gene tet(X4) in China. Front Microbiol 2023; 14:1130708. [PMID: 37180274 PMCID: PMC10171367 DOI: 10.3389/fmicb.2023.1130708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Accepted: 03/27/2023] [Indexed: 05/16/2023] Open
Abstract
Objectives Tigecycline is recognized as one of the last-line antibiotics to treat serious bacterial infection caused by carbapenem-resistant Klebsiella pneumoniae (CRKP). The plasmid-borne gene tet(X4) mediates high resistance to tigecycline. However, the prevalence and genetic context of tet(X4) in K. pneumoniae from various sources are not fully understood. Here, we investigated the prevalence of tet(X4)-positive K. pneumoniae and characterized the genetic context of tet(X4)-bearing plasmids in K. pneumoniae isolates. Methods Polymerase chain reaction (PCR) was used to detect the tet(X4) gene. The transferability of the tet(X4)-carrying plasmids was tested by conjugation assays. The Galleria mellonella infection model was used to test virulence of tet(X4)-positive strains. Whole-genome sequencing and genome-wide analysis were performed to identify the antimicrobial resistance and the virulence genes, and to clarify the genetic characteristics of the tet(X4)-positive isolates. Results Among 921 samples, we identified two tet(X4)-positive K. pneumoniae strains collected from nasal swabs of two pigs (0.22%, 2/921). The two tet(X4)-positive isolates exhibited high minimum inhibitory concentrations to tigecycline (32-256 mg/L) and tetracycline (256 mg/L). The plasmids carrying the tet(X4) gene can transfer from the donor strain K. pneumoniae to the recipient strain Escherichia coli J53. Genetic analysis of the complete sequence of two tet(X4)-carrying plasmids pTKPN_3-186k-tetX4 and pTKPN_8-216k-tetX4 disclosed that the tet(X4) gene was flanked by delta ISCR2 and IS1R, which may mediate the transmission of the tet(X4) gene. Conclusion The prevalence of tet(X4)-positive K. pneumoniae among different sources was low. ISCR2 and IS1R may contribute to the horizontal transfer of tet(X4) gene. Effective measures should be taken to prevent the transmission of tet(X4)-producing K. pneumoniae in humans or animals.
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Affiliation(s)
- Yanxian Yang
- Program in Pathobiology, the Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
- Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Diseases Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China
| | - Ruowen He
- Program in Pathobiology, the Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
- Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Diseases Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China
- Microbiome Medicine Center, Department of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Yiping Wu
- Program in Pathobiology, the Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
- Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Diseases Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China
| | - Mingyang Qin
- School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, China
- School of Public Health, Shandong University, Jinan, China
| | - Jieyun Chen
- Program in Pathobiology, the Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
- Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Diseases Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China
| | - Yu Feng
- Program in Pathobiology, the Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
- Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Diseases Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China
| | - Runping Zhao
- School of Laboratory Medicine, Chengdu Medical College, Chengdu, China
| | - Lei Xu
- School of Laboratory Medicine, Chengdu Medical College, Chengdu, China
| | - Xilong Guo
- Program in Pathobiology, the Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
- Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Diseases Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China
| | - Guo-Bao Tian
- Program in Pathobiology, the Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
- Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Key Laboratory of Tropical Diseases Control, Ministry of Education, Sun Yat-sen University, Guangzhou, China
| | - Min Dai
- School of Laboratory Medicine, Chengdu Medical College, Chengdu, China
- Min Dai,
| | - Bin Yan
- Program in Pathobiology, the Fifth Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangdong, China
- Advanced Medical Technology Center, The First Affiliated Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Department of Neonatal Surgery, Guangzhou Women and Children's Medical Center, Guangzhou, China
- Bin Yan,
| | - Li-Na Qin
- Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, China
- Guangdong Province Translational Forensic Medicine Engineering Technology Research Center, Sun Yat-sen University, Guangzhou, China
- *Correspondence: Li-Na Qin,
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8
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Stewart J, Judd LM, Jenney A, Holt KE, Wyres KL, Hawkey J. Epidemiology and genomic analysis of Klebsiella oxytoca from a single hospital network in Australia. BMC Infect Dis 2022; 22:704. [PMID: 36002802 PMCID: PMC9400251 DOI: 10.1186/s12879-022-07687-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 08/17/2022] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND Infections caused by Klebsiella oxytoca are the second most common cause of Klebsiella infections in humans. Most studies have focused on K. oxytoca outbreaks and few have examined the broader clinical context of K. oxytoca. METHODS Here, we collected all clinical isolates identified as K. oxytoca in a hospital microbiological diagnostic lab across a 15-month period (n = 239). Whole genome sequencing was performed on a subset of 92 isolates (all invasive, third-generation cephalosporin resistant (3GCR) and non-urinary isolates collected > 48 h after admission), including long-read sequencing on a further six isolates with extended-spectrum beta-lactamase or carbapenemase genes. RESULTS The majority of isolates were sensitive to antimicrobials, however 22 isolates were 3GCR, of which five were also carbapenem resistant. Genomic analyses showed those identified as K. oxytoca by the clinical laboratory actually encompassed four distinct species (K. oxytoca, Klebsiella michiganensis, Klebsiella grimontii and Klebsiella pasteurii), referred to as the K. oxytoca species complex (KoSC). There was significant diversity within the population, with only 10/67 multi-locus sequence types (STs) represented by more than one isolate. Strain transmission was rare, with only one likely event identified. Six isolates had extended spectrum beta-lactamase (blaSHV-12 and/or blaCTX-M-9) or carbapenemase (blaIMP-4) genes. One pair of K. michiganensis and K. pasteurii genomes carried identical blaIMP-4 IncL/M plasmids, indicative of plasmid transmission. CONCLUSION Whilst antimicrobial resistance was rare, the resistance plasmids were similar to those found in other Enterobacterales, demonstrating that KoSC has access to the same plasmid reservoir and thus there is potential for multi-drug resistance. Further genomic studies are required to improve our understanding of the KoSC population and facilitate investigation into the attributes of successful nosocomial isolates.
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Affiliation(s)
- James Stewart
- grid.413210.50000 0004 4669 2727Department of Infectious Diseases, Cairns Hospital, Cairns, QLD 4870 Australia
| | - Louise M. Judd
- grid.1002.30000 0004 1936 7857Department of Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC 3004 Australia
| | - Adam Jenney
- grid.1002.30000 0004 1936 7857Department of Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC 3004 Australia ,grid.1623.60000 0004 0432 511XMicrobiology Unit, Alfred Pathology Service, The Alfred Hospital Melbourne, Melbourne, VIC 3004 Australia
| | - Kathryn E. Holt
- grid.1002.30000 0004 1936 7857Department of Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC 3004 Australia ,grid.8991.90000 0004 0425 469XDepartment of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, WC1E 7HT UK
| | - Kelly L. Wyres
- grid.1002.30000 0004 1936 7857Department of Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC 3004 Australia
| | - Jane Hawkey
- grid.1002.30000 0004 1936 7857Department of Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC 3004 Australia
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9
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Choi EY, Waheed A, Seraj SM. Metastatic Klebsiella Pneumoniae in an Immunocompetent Patient: A Rare, Atypical Presentation of Klebsiella Syndrome. Cureus 2022; 14:e26156. [PMID: 35891875 PMCID: PMC9306396 DOI: 10.7759/cureus.26156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/21/2022] [Indexed: 11/18/2022] Open
Abstract
Metastatic Klebsiella pneumoniae (MKP) is a rare, atypical presentation of Klebsiella syndrome. The disease primarily affects patients with underlying immunocompromised status, but its prevalence in immunocompetent patients without any underlying illness is rare. We present a rare case of MKP in a 41-year-old Caucasian male without prior comorbidities who presented with blurry vision and was found to have MKP. The current case report also discusses the diagnostic modalities, complications, and treatment options of MKP.
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10
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Tuncer G, Aktas Z, Basaran S, Cagatay A, Eraksoy H. Biofilm formation of panresistant Klebsiella pneumoniae. Future Microbiol 2022; 17:723-735. [PMID: 35443798 DOI: 10.2217/fmb-2021-0108] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Introduction: The authors aimed to investigate the biofilm-forming features of panresistant Klebsiella pneumoniae (PRKp). Material & methods: The biofilm formations were shown under light microscope and laser scanning confocal microscopy. The optical densities of the wells were measured and classified according to biofilm-forming capacities. Results: The ratio of biofilm-forming K. pneumoniae was established to be 100%. All isolates were found to form high-level biofilms in classification compared with positive and negative controls. No significant difference was detected in the biofilm-forming capacities of K. pneumoniae strains isolated from different sample types. Conclusion: No previous study associated with PRKp isolates was identified in the literature search. There is a need for different approaches characterizing the biofilm-forming features of PRKp.
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Affiliation(s)
- Gulsah Tuncer
- Department of Infectious Diseases & Clinical Microbiology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, 34104, Turkey
| | - Zerrin Aktas
- Department of Microbiology & Clinical Microbiology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, 34104, Turkey
| | - Seniha Basaran
- Department of Infectious Diseases & Clinical Microbiology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, 34104, Turkey
| | - Atahan Cagatay
- Department of Infectious Diseases & Clinical Microbiology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, 34104, Turkey
| | - Haluk Eraksoy
- Department of Infectious Diseases & Clinical Microbiology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, 34104, Turkey
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11
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Epidemiology of infections and colonization caused by Klebsiella pneumoniae NDM in the Mazovian Voivodeship in 2016–2017. POSTEP HIG MED DOSW 2022. [DOI: 10.2478/ahem-2022-0024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Introduction
Klebsiella pneumoniae is a common cause of antimicrobial-resistant opportunistic infections in hospitalized patients. Due to acquired resistance to multiple antimicrobials, K. pneumoniae is a particular threat in health care. The aim of this study was the assessment of the epidemiological situation related to the spread of symptomatic infections and colonization caused by K. pneumoniae New Delhi metallo-β-lactamase (NDM) in the Mazovian Voivodeship in 2016–2017.
Materials and Methods
The study included data collected between 2016 and 2017 from 168 hospitals located in and outside of Warsaw but limited to the Mazovian Voivodeship. Data was extracted from reports on suspected epidemic outbreaks and the elimination of outbreaks as well as annual reports on nosocomial infections and alarm pathogens.
Results
The incidence of infections caused by K. pneumoniae NDM (symptomatic and asymptomatic) was 0.96/1,000 hospitalizations in 2016 and 2.04/1,000 hospitalizations in 2017. In 2016, hospitals in the Mazovian Voivodeship reported 50 transmissions of K. pneumoniae NDM. In 2017, this value increased to 74. The risk of symptomatic infection was higher in hospitals outside of Warsaw than in hospitals in Warsaw, while risk of colonization was higher in hospitals in Warsaw.
Conclusions
The epidemiological situation related to infections and colonization caused by K. pneumoniae NDM in the Mazovian Voivodeship is disadvantageous, which implies the necessity to monitor anti-epidemic measures. The epidemic situation in hospitals outside of Warsaw seems to be worse compared to hospitals in Warsaw, which have higher risks of symptomatic infection caused by K. pneumoniae NDM.
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12
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Li P, Zhang Y, Yan F, Zhou X. Characteristics of a Bacteriophage, vB_Kox_ZX8, Isolated From Clinical Klebsiella oxytoca and Its Therapeutic Effect on Mice Bacteremia. Front Microbiol 2021; 12:763136. [PMID: 34925270 PMCID: PMC8678519 DOI: 10.3389/fmicb.2021.763136] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 11/04/2021] [Indexed: 12/13/2022] Open
Abstract
Klebsiella oxytoca is an important nosocomial and community-acquired opportunistic pathogenic Klebsiella and has become the second most prevalent strain in the clinic after K. pneumoniae. However, there have been few reports of bacteriophages used for treating K. oxytoca. In this study, a novel bacteriophage, vB_Kox_ZX8, which specifically infects K. oxytoca AD3, was isolated for the first time from human fecal samples. The biological characteristics of vB_Kox_ZX8 showed an incubation period of 10 min, a burst size of 74 PFU/cell, and a stable pH range of 3-11. Genomic bioinformatics studies of vB_Kox_ZX8 showed that it belongs to the genus Przondovirus, subfamily Studiervirinae, family Autographiviridae. The genome of vB_Kox_ZX8 is 39,398 bp in length and contains 46 putative open reading frames encoding functional proteins, such as DNA degradation, packaging, structural, lysin-holin, and hypothetical proteins. We further investigated the efficacy of vB_Kox_ZX8 phage in the treatment of mice with bacteremia caused by K. oxytoca infection. The results showed that vB_Kox_ZX8 (5 × 109 PFU/mouse) injected intraperitoneally alone was metabolized rapidly in BALB/c mice, and no significant side effects were observed in the control and treatment groups. Importantly, intraperitoneal injection with a single dose of phage vB_Kox_ZX8 (5 × 107 PFU/mouse) for 1 h post-infection saved 100% of BALB/c mice from bacteremia induced by intraperitoneal challenge with a minimum lethal dose of K. oxytoca AD3. However, all negative control mice injected with PBS alone died. Owing to its good safety, narrow host infectivity, high lysis efficiency in vitro, and good in vivo therapeutic effect, phage vB_Kox_ZX8 has the potential to be an excellent antibacterial agent for clinical K. oxytoca-caused infections.
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Affiliation(s)
- Ping Li
- Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
| | - Yangheng Zhang
- Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China
| | - Fuhua Yan
- Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China
| | - Xin Zhou
- Institute of Comparative Medicine, College of Veterinary Medicine, Yangzhou University, Yangzhou, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou University, Yangzhou, China.,Joint International Research Laboratory of Agriculture and Agri-Product Safety, The Ministry of Education of China, Yangzhou University, Yangzhou, China
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13
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Diffuse-Type Tenosynovial Giant Cell Tumor of the Knee with Concurrent Polymicrobial Infection ( Klebsiella oxytoca and Group B Streptococcus). Case Rep Infect Dis 2021; 2021:5523212. [PMID: 34557317 PMCID: PMC8455224 DOI: 10.1155/2021/5523212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 06/21/2021] [Accepted: 08/06/2021] [Indexed: 11/25/2022] Open
Abstract
Tenosynovial giant cell tumors (TGCT) are a rare class of benign proliferative tumors that are classified according to their presentation: localized-type (L-TGCT) or diffuse-type (D-TGCT). TGCT is synonymous with pigmented villonodular synovitis (PVNS). We describe the unique case of a 56-year-old obese male with type 2 diabetes who had polymicrobial septic arthritis of his left knee joint with concurrent D-TGCT in the same knee. While on a vacation, he noticed spontaneous left knee pain and swelling with an acute onset of fever. He was diagnosed with septic arthritis that was attributed to hematogenous spread from a leg laceration. The septic arthritis was treated with arthroscopic lavage and debridement, including simultaneous excision of the D-TGCT lesions, followed by intravenous ceftriaxone. Cultures of the synovial tissue that were obtained during arthroscopy grew Klebsiella oxytoca and beta-hemolytic (group B) Streptococcus agalactiae. We were not able to find another reported case of any joint with (1) a polymicrobial bacterial infection that included Klebsiella oxytoca and (2) concurrent bacterial septic arthritis and TGCT.
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14
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Neog N, Phukan U, Puzari M, Sharma M, Chetia P. Klebsiella oxytoca and Emerging Nosocomial Infections. Curr Microbiol 2021; 78:1115-1123. [PMID: 33656584 DOI: 10.1007/s00284-021-02402-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2020] [Accepted: 02/10/2021] [Indexed: 12/12/2022]
Abstract
Klebsiella oxytoca is rising as a significant opportunistic pathogen causing nosocomial infections in neonates as well as adults. This pathogen's prevalence varies from 2 to 24%, but outbreaks of infections due to multidrug-resistant strains can be fatal in immunocompromised individuals with comorbidities. Klebsiella oxytoca is responsible for a wide range of ailments from colitis to infective endocarditis, other than the common urinary and respiratory tract infections. The microbe's pathogenicity has been attributed to cytotoxins' production- Tilivalline and Tilimycin, in some intestinal disorders. Klebsiella oxytoca is reported to be resistant to a wide range of antibiotics. Here, we have tried to showcase a brief overview of the emergence of Klebsiella oxytoca in healthcare facilities and the nature of resistance in this species of Klebsiella.
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Affiliation(s)
- Nakul Neog
- Department of Life Sciences, Dibrugarh Univerity, Dibrugarh, Assam, 786004, India
| | - Upasana Phukan
- Department of Life Sciences, Dibrugarh Univerity, Dibrugarh, Assam, 786004, India
| | - Minakshi Puzari
- Department of Life Sciences, Dibrugarh Univerity, Dibrugarh, Assam, 786004, India
| | - Mohan Sharma
- Department of Life Sciences, Dibrugarh Univerity, Dibrugarh, Assam, 786004, India
| | - Pankaj Chetia
- Department of Life Sciences, Dibrugarh Univerity, Dibrugarh, Assam, 786004, India.
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15
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Mirzaei R, Mohammadzadeh R, Sholeh M, Karampoor S, Abdi M, Dogan E, Moghadam MS, Kazemi S, Jalalifar S, Dalir A, Yousefimashouf R, Mirzaei E, Khodavirdipour A, Alikhani MY. The importance of intracellular bacterial biofilm in infectious diseases. Microb Pathog 2020; 147:104393. [PMID: 32711113 DOI: 10.1016/j.micpath.2020.104393] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 07/07/2020] [Accepted: 07/08/2020] [Indexed: 12/17/2022]
Abstract
Various bacterial species, previously known as extracellular pathogens, can reside inside different host cells by adapting to intracellular modes by forming microbial aggregates with similar characteristics to bacterial biofilms. Additionally, bacterial invasion of human cells leads to failure in antibiotic therapy, as most conventional anti-bacterial agents cannot reach intracellular biofilm in normal concentrations. Various studies have shown that bacteria such as uropathogenic Escherichia coli, Pseudomonas aeruginosa, Borrelia burgdorferi,Moraxella catarrhalis, non-typeable Haemophilus influenzae, Streptococcus pneumonia, and group A Streptococci produce biofilm-like structures within the host cells. For the first time in this review, we will describe and discuss the new information about intracellular bacterial biofilm formation and its importance in bacterial infectious diseases.
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Affiliation(s)
- Rasoul Mirzaei
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran; Student Research Committee, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Rokhsareh Mohammadzadeh
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Sholeh
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Sajad Karampoor
- Department of Virology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Milad Abdi
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Student Research Committee, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Eyup Dogan
- Department of Basic Biotechnology, Biotechnology Institute, Ankara, Turkey
| | - Mohammad Shokri Moghadam
- Department of Microbiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
| | - Sima Kazemi
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Saba Jalalifar
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Amine Dalir
- Department of Microbiology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Rasoul Yousefimashouf
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Ebrahim Mirzaei
- Department of Medical Genetics and Molecular Biology, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Amir Khodavirdipour
- Division of Humann Genetics, Department of Anatomy, St. John's Hospital, Bangalore, India
| | - Mohammad Yousef Alikhani
- Department of Microbiology, School of Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
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16
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Skowron K, Wiktorczyk N, Kwiecińska‐Piróg J, Sękowska A, Wałecka‐Zacharska E, Gospodarek‐Komkowska E. Elimination of
Klebsiella pneumoniae
NDM from the air and selected surfaces in hospital using radiant catalytic ionization. Lett Appl Microbiol 2019; 69:333-338. [DOI: 10.1111/lam.13223] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 09/09/2019] [Accepted: 09/13/2019] [Indexed: 11/28/2022]
Affiliation(s)
- K. Skowron
- Department of Microbiology Nicolaus Copernicus University in Toruń Collegium Medicum of L. Rydygier in Bydgoszcz Bydgoszcz Poland
| | - N. Wiktorczyk
- Department of Microbiology Nicolaus Copernicus University in Toruń Collegium Medicum of L. Rydygier in Bydgoszcz Bydgoszcz Poland
| | - J. Kwiecińska‐Piróg
- Department of Microbiology Nicolaus Copernicus University in Toruń Collegium Medicum of L. Rydygier in Bydgoszcz Bydgoszcz Poland
| | - A. Sękowska
- Department of Microbiology Nicolaus Copernicus University in Toruń Collegium Medicum of L. Rydygier in Bydgoszcz Bydgoszcz Poland
| | - E. Wałecka‐Zacharska
- Department of Food Hygiene and Consumer Health Wrocław University of Environmental and Life Sciences Wrocław Poland
| | - E. Gospodarek‐Komkowska
- Department of Microbiology Nicolaus Copernicus University in Toruń Collegium Medicum of L. Rydygier in Bydgoszcz Bydgoszcz Poland
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17
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Naranjo E, Merfa MV, Ferreira V, Jain M, Davis MJ, Bahar O, Gabriel DW, De La Fuente L. Liberibacter crescens biofilm formation in vitro: establishment of a model system for pathogenic 'Candidatus Liberibacter spp.'. Sci Rep 2019; 9:5150. [PMID: 30914689 PMCID: PMC6435755 DOI: 10.1038/s41598-019-41495-5] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 03/11/2019] [Indexed: 11/23/2022] Open
Abstract
The Liberibacter genus comprises insect endosymbiont bacterial species that cause destructive plant diseases, including Huanglongbing in citrus and zebra chip in potato. To date, pathogenic 'Candidatus Liberibacter spp.' (CLs) remain uncultured, therefore the plant-associated Liberibacter crescens (Lcr), only cultured species of the genus, has been used as a biological model for in vitro studies. Biofilm formation by CLs has been observed on the outer midgut surface of insect vectors, but not in planta. However, the role of biofilm formation in the life cycle of these pathogens remains unclear. Here, a model system for studying CLs biofilms was developed using Lcr. By culture media modifications, bovine serum albumin (BSA) was identified as blocking initial cell-surface adhesion. Removal of BSA allowed for the first time observation of Lcr biofilms. After media optimization for biofilm formation, we demonstrated that Lcr attaches to surfaces, and form cell aggregates embedded in a polysaccharide matrix both in batch cultures and under flow conditions in microfluidic chambers. Biofilm structures may represent excellent adaptive advantages for CLs during insect vector colonization helping with host retention, immune system evasion, and transmission. Future studies using the Lcr model established here will help in the understanding of the biology of CLs.
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Affiliation(s)
- Eber Naranjo
- Department of Entomology and Plant Pathology, Auburn University, Auburn, USA
| | - Marcus V Merfa
- Department of Entomology and Plant Pathology, Auburn University, Auburn, USA
| | - Virginia Ferreira
- Bioscience Department, College of Chemistry, University of the Republic, Montevideo, Uruguay
| | - Mukesh Jain
- Department of Plant Pathology, University of Florida, Gainesville, USA
| | - Michael J Davis
- Citrus Research and Education Center, University of Florida, Gainesville, USA
| | - Ofir Bahar
- Department of Plant Pathology and Weed Research, ARO - Volcani Center, Bet-Dagan, Israel
| | - Dean W Gabriel
- Department of Plant Pathology, University of Florida, Gainesville, USA
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18
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Vázquez-Martínez ER, García-Gómez E, Camacho-Arroyo I, González-Pedrajo B. Sexual dimorphism in bacterial infections. Biol Sex Differ 2018; 9:27. [PMID: 29925409 PMCID: PMC6011518 DOI: 10.1186/s13293-018-0187-5] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 06/08/2018] [Indexed: 12/21/2022] Open
Abstract
Background Sex differences are important epidemiological factors that impact in the frequency and severity of infectious diseases. A clear sexual dimorphism in bacterial infections has been reported in both humans and animal models. Nevertheless, the molecular mechanisms involved in this gender bias are just starting to be elucidated. In the present article, we aim to review the available data in the literature that report bacterial infections presenting a clear sexual dimorphism, without considering behavioral and social factors. Main body The sexual dimorphism in bacterial infections has been mainly attributed to the differential levels of sex hormones between males and females, as well as to genetic factors. In general, males are more susceptible to gastrointestinal and respiratory bacterial diseases and sepsis, while females are more susceptible to genitourinary tract bacterial infections. However, these incidences depend on the population evaluated, animal model and the bacterial species. Female protection against bacterial infections and the associated complications is assumed to be due to the pro-inflammatory effect of estradiol, while male susceptibility to those infections is associated with the testosterone-mediated immune suppression, probably via their specific receptors. Recent studies indicate that the protective effect of estradiol depends on the estrogen receptor subtype and the specific tissue compartment involved in the bacterial insult, suggesting that tissue-specific expression of particular sex steroid receptors contributes to the susceptibility to bacterial infections. Furthermore, this gender bias also depends on the effects of sex hormones on specific bacterial species. Finally, since a large number of genes related to immune functions are located on the X chromosome, X-linked mosaicism confers a highly polymorphic gene expression program that allows women to respond with a more expanded immune repertoire as compared with men. Conclusion Notwithstanding there is increasing evidence that confirms the sexual dimorphism in certain bacterial infections and the molecular mechanisms associated, further studies are required to clarify conflicting data and to determine the role of specific hormone receptors involved in the gender bias of bacterial infections, as well as their potential as therapeutic targets.
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Affiliation(s)
- Edgar Ricardo Vázquez-Martínez
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, Mexico
| | - Elizabeth García-Gómez
- Unidad de Investigación en Reproducción Humana, Consejo Nacional de Ciencia y Tecnología (CONACyT)-Instituto Nacional de Perinatología, Ciudad de México, Mexico
| | - Ignacio Camacho-Arroyo
- Unidad de Investigación en Reproducción Humana, Instituto Nacional de Perinatología-Facultad de Química, Universidad Nacional Autónoma de México (UNAM), Ciudad de México, Mexico
| | - Bertha González-Pedrajo
- Departamento de Genética Molecular, Instituto de Fisiología Celular, UNAM, Ciudad Universitaria, Av. Universidad 3000, Coyoacán, 04510, Ciudad de México, Mexico.
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19
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Vading M, Nauclér P, Kalin M, Giske CG. Invasive infection caused by Klebsiella pneumoniae is a disease affecting patients with high comorbidity and associated with high long-term mortality. PLoS One 2018; 13:e0195258. [PMID: 29624618 PMCID: PMC5889183 DOI: 10.1371/journal.pone.0195258] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2017] [Accepted: 03/19/2018] [Indexed: 01/03/2023] Open
Abstract
Klebsiella pneumoniae (KP) is after Escherichia coli (EC) the most common gram-negative species causing invasive infections. Herein, we analyzed risk factors and prognosis in invasive infections caused by KP versus EC, in an area with low antimicrobial resistance. Moreover, we compared antimicrobial resistance and relative prevalence of KP and EC (KP/EC-ratio) in different European countries, using EARS-Net data. Adult patients admitted to Karolinska University Hospital 2006–2012 with invasive infection caused by KP (n = 599) were matched regarding sex and age with patients infected by EC. The medical records were retrospectively reviewed. Comorbidity was adjusted for with multivariable analysis. European data were retrieved from the EARS-Net database. No differences were observed in 7- and 30-day mortality between the groups. The 90-day mortality was significantly higher in the KP cohort (26% versus 17%, p<0.001), but not after adjusting for comorbidity. Malignancy was seen in 53% of the patients with KP versus 38% with EC, OR 1.86 (1.34–2.58). A significant increase in the rate of ESBL-production was observed in EC, but not in KP. The KP/EC-ratio remained stable. In contrast, European data showed increasing percentages of isolates non-susceptible to third-generation cephalosporins in EC and KP, and increasing KP/EC-ratio. Invasive infection caused by KP is a disease affecting patients with high comorbidity and associated with high 90-d mortality. The stable KP/EC-ratio and low occurrence of antimicrobial resistance in data from Karolinska University Hospital compared to aggregate data from 20 EARS-Net countries could be related to absence of clonal spread of multidrug-resistant KP.
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Affiliation(s)
- M. Vading
- Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Infectious Diseases, Danderyds Hospital, Stockholm, Sweden
- * E-mail:
| | - P. Nauclér
- Department of Infectious Diseases, Karolinska University Hospital Solna, Stockholm, Sweden
- Department of Medicine Solna, Infectious Diseases Unit, Karolinska Institutet, Stockholm, Sweden
| | - M. Kalin
- Department of Medicine Solna, Infectious Diseases Unit, Karolinska Institutet, Stockholm, Sweden
| | - C. G. Giske
- Division of Clinical Microbiology, Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Clinical Microbiology, Karolinska University Hospital Solna, Stockholm, Sweden
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Zheng X, Wang JF, Xu WL, Xu J, Hu J. Clinical and molecular characteristics, risk factors and outcomes of Carbapenem-resistant Klebsiella pneumoniae bloodstream infections in the intensive care unit. Antimicrob Resist Infect Control 2017; 6:102. [PMID: 29026535 PMCID: PMC5625719 DOI: 10.1186/s13756-017-0256-2] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 09/04/2017] [Indexed: 11/10/2022] Open
Abstract
Background To analyze the clinical characteristics and outcomes of carbapenem-resistant Klebsiella pneumoniae (CRKp) and carbapenem-susceptible K. pneumoniae (CSKp) bloodstream infections (BSIs), and to study the risk factors for development of CRKp BSI and K. pneumoniae BSI-related mortality. Methods A retrospective case control study of patients with K. pneumoniae BSI was conducted in the intensive care unit of the First Affiliated Hospital, Medical of College, Zhejiang University from January 2013 to December 2014. Carbapenem resistance was defined in accordance with the Clinical and Laboratory Standards Institute 2016 guidelines. Risk factors for the development of CRKp BSI and risk factors for mortality due to K. pneumoniae BSI were assessed. Virulence genes were detected by polymerase chain reaction assay. Results In total, 48 patients were enrolled in the study, including 31 (65%) patients with CRKp BSI and 17 (35%) patients with CSKp BSI. CSKp infection was associated with more severe clinical symptoms, particularly a higher serum creatinine level (165.06 ± 127.01 in the CSKp group vs. 93.77 ± 84.35 μmol/L in the CRKp group, p = 0.039), but there was no significant difference in prognosis between the CSKp and CRKp groups. On multivariate analysis, indwelling central venous catheter (p = 0.045) was the only factor independently associated with CRKp bacteremia. However, the mortality of K. pneumoniae BSI patients was not correlated with carbapenem resistance. In addition, the isolates had diverse clonality and different origins. The frequency of detection of the allS and magA virulence genes was higher in the CSKp group than in the CRKp group (alls p = 0.04; magA p = 0.047). Conclusions Patients in the CSKp group experienced more severe clinical symptoms, although mortality did not differ significantly between the CRKp and CSKp groups. An indwelling central venous catheter was the only factor independently associated with CRKp BSI. The mortality of patients with K. pneumoniae BSI was not associated with carbapenem resistance. The frequency of virulence genes was higher in the CSKp group than in the CRKp group.
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Affiliation(s)
- Xia Zheng
- Intensive Care Unit, The First Affiliated Hospital, College of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003 People's Republic of China
| | - Jian-Feng Wang
- Department of Respiratory Diseases, The Affiliated Hospital of Hangzhou Normal University, Hangzhou, Zhejiang, No. 126 Wenzhou Road, Hangzhou, 310009 People's Republic of China
| | - Wang-Lan Xu
- Intensive Care Unit, Hospital of Zhejiang General Corps of Armed Police Forces, No. 16 Nanhu Road, Jiaxing, 314000 Zhejiang, People's Republic of China
| | - Jun Xu
- Intensive Care Unit, The First Affiliated Hospital, College of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003 People's Republic of China
| | - Juan Hu
- Intensive Care Unit, The First Affiliated Hospital, College of Medicine, Zhejiang University, 79 Qingchun Road, Hangzhou, 310003 People's Republic of China
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Carbapenemase-Producing Klebsiella pneumoniae, a Key Pathogen Set for Global Nosocomial Dominance. Antimicrob Agents Chemother 2015; 59:5873-84. [PMID: 26169401 DOI: 10.1128/aac.01019-15] [Citation(s) in RCA: 548] [Impact Index Per Article: 60.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The management of infections due to Klebsiella pneumoniae has been complicated by the emergence of antimicrobial resistance, especially to carbapenems. Resistance to carbapenems in K. pneumoniae involves multiple mechanisms, including the production of carbapenemases (e.g., KPC, NDM, VIM, OXA-48-like), as well as alterations in outer membrane permeability mediated by the loss of porins and the upregulation of efflux systems. The latter two mechanisms are often combined with high levels of other types of β-lactamases (e.g., AmpC). K. pneumoniae sequence type 258 (ST258) emerged during the early to mid-2000s as an important human pathogen and has spread extensively throughout the world. ST258 comprises two distinct lineages, namely, clades I and II, and it seems that ST258 is a hybrid clone that was created by a large recombination event between ST11 and ST442. Incompatibility group F plasmids with blaKPC have contributed significantly to the success of ST258. The optimal treatment of infections due to carbapenemase-producing K. pneumoniae remains unknown. Some newer agents show promise for treating infections due to KPC producers; however, effective options for the treatment of NDM producers remain elusive.
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LU HUIXIA, WU QI, YANG HUIJUN. DUOX2 promotes the elimination of the Klebsiella pneumoniae strain K5 from T24 cells through the reactive oxygen species pathway. Int J Mol Med 2015; 36:551-8. [DOI: 10.3892/ijmm.2015.2234] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 05/25/2015] [Indexed: 11/06/2022] Open
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Broberg CA, Palacios M, Miller VL. Klebsiella: a long way to go towards understanding this enigmatic jet-setter. F1000PRIME REPORTS 2014; 6:64. [PMID: 25165563 PMCID: PMC4126530 DOI: 10.12703/p6-64] [Citation(s) in RCA: 87] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Klebsiella pneumoniae is the causative agent of a variety of diseases, including pneumonia, urinary tract infections, septicemia, and the recently recognized pyogenic liver abscesses (PLA). Renewed efforts to identify and understand the bacterial determinants required to cause disease have come about because of the worldwide increase in the isolation of strains resistant to a broad spectrum of antibiotics. The recent increased isolation of carbapenem-resistant strains further reduces the available treatment options. The rapid geographic spread of the resistant isolates and the spread to other pathogens are of particular concern. For many years, the best characterized virulence determinants were capsule, lipopolysaccharide, siderophores, and types 1 and 3 fimbriae. Recent efforts to expand this list include in vivo screens and whole-genome sequencing. However, we still know little about how this bacterium is able to cause disease. Some recent clonal analyses of K. pneumoniae strains indicate that there are distinct clonal groups, some of which may be associated with specific disease syndromes. However, what makes one clonal group more virulent and what changes the disease pattern are not yet clear and remain important questions for the future.
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Affiliation(s)
- Christopher A. Broberg
- Department of Microbiology and Immunology, The University of North Carolina, Chapel Hill125 Mason Farm Road, 6101 Marsico Hall, Chapel Hill, NC 27599-7290USA
| | - Michelle Palacios
- Department of Microbiology and Immunology, The University of North Carolina, Chapel Hill125 Mason Farm Road, 6101 Marsico Hall, Chapel Hill, NC 27599-7290USA
| | - Virginia L. Miller
- Department of Microbiology and Immunology, The University of North Carolina, Chapel Hill125 Mason Farm Road, 6101 Marsico Hall, Chapel Hill, NC 27599-7290USA
- Department of Genetics, The University of North Carolina, Chapel Hill120 Mason Farm Road, 5000D Genetic Medicine Building, CB#7264, Chapel Hill, NC 27599USA
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Harada Y, Morinaga Y, Kaku N, Nakamura S, Uno N, Hasegawa H, Izumikawa K, Kohno S, Yanagihara K. In vitro and in vivo activities of piperacillin-tazobactam and meropenem at different inoculum sizes of ESBL-producing Klebsiella pneumoniae. Clin Microbiol Infect 2014; 20:O831-9. [PMID: 24813594 DOI: 10.1111/1469-0691.12677] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2014] [Revised: 05/07/2014] [Accepted: 05/07/2014] [Indexed: 01/21/2023]
Abstract
The inoculum effect is a laboratory phenomenon in which the minimal inhibitory concentration (MIC) of an antibiotic is increased when a large number of organisms are exposed. Due to the emergence of extended-spectrum β-lactamase-producing Klebsiella pneumoniae (ESBL-Kpn) infections, the inoculum effect of ESBL-Kpn on β-lactams was studied in vitro and in vivo using an experimental model of pneumonia. The in vitro inoculum effect of 45 clinical ESBL-Kpn isolates on β-lactams was evaluated at standard (10(5) CFU/mL) and high (10(7) CFU/mL) organism concentrations. The MIC50 of piperacillin-tazobactam, cefotaxime and cefepime was increased eight-fold or more and that of meropenem was increased two-fold. The in vivo inoculum effect was evaluated in an ESBL-Kpn pneumonia mouse model treated with bacteriostatic effect-adjusted doses of piperacillin-tazobactam (1000 mg/kg four times daily, %T>MIC; 32.60%) or meropenem (100 mg/kg twice daily, %T>MIC; 28.65%) at low/standard (10(4) CFU/mouse) and high (10(6) CFU/mouse) inocula. In mice administered a low inoculum, no mice died after treatment with piperacillin-tazobactam or meropenem, whereas all the control mice died. In contrast, in the high inoculum model, all mice in the piperacillin-tazobactam-treated group died, whereas all meropenem-treated mice survived and had a decreased bacterial load in the lungs and no invasion into the blood. In conclusion, meropenem was more resistant to the inoculum effect of ESBL-Kpn than piperacillin-tazobactam both in vitro and in vivo. In the management of severe pneumonia caused by ESBL-Kpn, carbapenems may be the drugs of choice to achieve a successful outcome.
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Affiliation(s)
- Y Harada
- Department of Laboratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan; Second Department of Internal Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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Kostakioti M, Hadjifrangiskou M, Hultgren SJ. Bacterial biofilms: development, dispersal, and therapeutic strategies in the dawn of the postantibiotic era. Cold Spring Harb Perspect Med 2013; 3:a010306. [PMID: 23545571 DOI: 10.1101/cshperspect.a010306] [Citation(s) in RCA: 502] [Impact Index Per Article: 45.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Biofilm formation constitutes an alternative lifestyle in which microorganisms adopt a multicellular behavior that facilitates and/or prolongs survival in diverse environmental niches. Biofilms form on biotic and abiotic surfaces both in the environment and in the healthcare setting. In hospital wards, the formation of biofilms on vents and medical equipment enables pathogens to persist as reservoirs that can readily spread to patients. Inside the host, biofilms allow pathogens to subvert innate immune defenses and are thus associated with long-term persistence. Here we provide a general review of the steps leading to biofilm formation on surfaces and within eukaryotic cells, highlighting several medically important pathogens, and discuss recent advances on novel strategies aimed at biofilm prevention and/or dissolution.
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Affiliation(s)
- Maria Kostakioti
- Department of Molecular Microbiology and Microbial Pathogenesis, Washington University in Saint Louis School of Medicine, St. Louis, MO 63110-1010, USA
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Tian LT, Yao K, Zhang XY, Zhang ZD, Liang YJ, Yin DL, Lee L, Jiang HC, Liu LX. Liver abscesses in adult patients with and without diabetes mellitus: an analysis of the clinical characteristics, features of the causative pathogens, outcomes and predictors of fatality: a report based on a large population, retrospective study in China. Clin Microbiol Infect 2012; 18:E314-30. [PMID: 22676078 DOI: 10.1111/j.1469-0691.2012.03912.x] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
In China, there are four types of liver abscesses (LAs) that meet the clinical criteria. Pyogenic liver abscesses (PLAs) and amoebic liver abscesses (ALAs) are two of the most common types of abscesses, followed by fungal liver abscesses (FLAs) and hydatid secondary liver abscesses (HsLAs). Diabetes mellitus (DM) is associated with the development of PLAs. However, there is a lack of population-based studies that have evaluated the underlying relationship between LAs (mainly PLAs and FLAs) and DM. We conducted a retrospective study based on a large population to identify the potential differences and factors that affect the mortality of PLA patients in DM and non-DM groups. Our results revealed that the prevalence of DM is 44.3% (158/357) in PLA patients and 35.3% (18/51) in FLA patients. Compared with the non-DM patients, statistically significant differences were found in DM patients according to symptomatology, clinical manifestations, laboratory findings, microbiological characteristics, antimicrobial resistance, clinical treatments and outcomes in relation to mortality. In addition, the status of antibiotic resistance to E. coli and K. pneumoniae, which were isolated from the patient samples, is severe in the area in which the study was conducted. Regarding the treatment of PLAs, our study indicated that broad-spectrum antimicrobial therapy and drug combinations should be recommended and initiated before the pathogens are cultured and identified. In the clinic, therapies that combine percutaneous drainage with antibiotics and surgery with antibiotics are the two most useful strategies for treating an LA. These two combined treatments resulted in satisfactory cure rates. In the DM and non-DM groups, the cure rates for percutaneous drainage with antibiotics were 90.3% and 92.0%, respectively, and the cure rates for surgery with antibiotics were 93.9% and 95.2%, respectively.
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Affiliation(s)
- L-T Tian
- Department of General Surgery, the First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang Province, China.
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Bojer MS, Struve C, Ingmer H, Hansen DS, Krogfelt KA. Heat resistance mediated by a new plasmid encoded Clp ATPase, ClpK, as a possible novel mechanism for nosocomial persistence of Klebsiella pneumoniae. PLoS One 2010; 5:e15467. [PMID: 21085699 PMCID: PMC2976762 DOI: 10.1371/journal.pone.0015467] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2010] [Accepted: 09/29/2010] [Indexed: 12/03/2022] Open
Abstract
Klebsiella pneumoniae is an important opportunistic pathogen and a frequent cause of nosocomial infections. We have characterized a K. pneumoniae strain responsible for a series of critical infections in an intensive care unit over a two-year period. The strain was found to be remarkably thermotolerant providing a conceivable explanation of its persistence in the hospital environment. This marked phenotype is mediated by a novel type of Clp ATPase, designated ClpK. The clpK gene is encoded by a conjugative plasmid and we find that the clpK gene alone renders an otherwise sensitive E. coli strain resistant to lethal heat shock. Furthermore, one third of a collection of nosocomial K. pneumoniae isolates carry clpK and exhibit a heat resistant phenotype. The discovery of ClpK as a plasmid encoded factor and its profound impact on thermal stress survival sheds new light on the biological relevance of Clp ATPases in acquired environmental fitness and highlights the challenges of mobile genetic elements in fighting nosocomial infections.
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Affiliation(s)
- Martin Saxtorph Bojer
- Department of Microbiological Surveillance and Research, Statens Serum Institut, Copenhagen, Denmark
| | - Carsten Struve
- Department of Microbiological Surveillance and Research, Statens Serum Institut, Copenhagen, Denmark
- * E-mail:
| | - Hanne Ingmer
- Department of Veterinary Pathobiology, Faculty of Life Sciences, University of Copenhagen, Frederiksberg, Denmark
| | - Dennis Schrøder Hansen
- Department of Clinical Microbiology, Hvidovre Hospital, Hvidovre, Denmark
- Department of Clinical Microbiology, Hillerød Hospital, Hillerød, Denmark
| | - Karen Angeliki Krogfelt
- Department of Microbiological Surveillance and Research, Statens Serum Institut, Copenhagen, Denmark
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Ghenghesh KS, Elkateb E, Berbash N, Abdel Nada R, Ahmed SF, Rahouma A, Seif-Enasser N, Elkhabroun MA, Belresh T, Klena JD. Uropathogens from diabetic patients in Libya: virulence factors and phylogenetic groups of Escherichia coli isolates. J Med Microbiol 2009; 58:1006-1014. [PMID: 19528169 DOI: 10.1099/jmm.0.007146-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Urinary tract infections (UTIs) in patients with diabetes mellitus (DM) are reported mainly from developed countries. In addition to this underreporting from developing countries, there is a lack of information pertaining to the virulence factors (VFs) and phylogenetic grouping of uropathogenic Escherichia coli (UPEC) from DM and non-DM patients in developing countries. Between July 2005 and June 2006, urine specimens were collected from 135 DM and 164 non-DM patients, all with clinically diagnosed UTIs, attending Elkhadra Hospital and the Diabetic Center in Tripoli, Libya. Specimens were examined for different uropathogens using standard microbiological procedures. Isolated uropathogens were tested for their susceptibility to antimicrobial agents by a disc diffusion method. In addition, UPEC was grouped phylogenetically by PCR and subsequently tested for 19 VFs. Uropathogens were isolated from 77 (57 %) of the DM group and from 110 (67 %) of the non-DM group (P >0.05). E. coli was isolated from 18 (13 %) and 29 (18 %), Klebsiella species from 18 (13 %) and 23 (14 %), and Staphylococcus aureus from 12 (9 %) and 12 (7 %) of the DM and non-DM groups, respectively (P >0.05). Age, gender, education level and marital status had no significant influence on the isolation rates of different organisms from the DM group compared with the non-DM group. With very few exceptions, no differences were observed in the antimicrobial resistance profiles of uropathogens from the DM and non-DM patients. In addition, UPEC from the DM patients was significantly less virulent and was associated with phylogenetic group A, whilst UPEC from the non-DM patients was significantly more virulent and was associated with group D. The results of our surveillance of UTI infections in DM patients agree, in general, with observations reported previously from several developed countries.
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Affiliation(s)
- Khalifa Sifaw Ghenghesh
- Department of Microbiology and Immunology, Faculty of Medicine, Al-Fateh University for Medical Sciences, Tripoli, Libya
| | - Einass Elkateb
- Department of Zoology, Faculty of Sciences, Al-Fateh University, Tripoli, Libya
| | - Nuri Berbash
- Department of Zoology, Faculty of Sciences, Al-Fateh University, Tripoli, Libya
| | - Rania Abdel Nada
- Clinical Trials Program, Molecular Epidemiology Unit, NAMRU-3, Cairo, Egypt
| | - Salwa F Ahmed
- Clinical Trials Program, Molecular Epidemiology Unit, NAMRU-3, Cairo, Egypt
| | - Amal Rahouma
- Department of Microbiology and Immunology, Faculty of Medicine, Al-Fateh University for Medical Sciences, Tripoli, Libya
| | - Nadia Seif-Enasser
- Department of Microbiology and Immunology, Faculty of Medicine, Al-Fateh University for Medical Sciences, Tripoli, Libya
| | | | | | - John D Klena
- Clinical Trials Program, Molecular Epidemiology Unit, NAMRU-3, Cairo, Egypt
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Hakeem LM, Bhattacharyya DN, Lafong C, Janjua KS, Serhan JT, Campbell IW. Diversity and complexity of urinary tract infection in diabetes mellitus. ACTA ACUST UNITED AC 2009. [DOI: 10.1177/1474651409105654] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Urinary tract infections (UTIs) are a common burden in patients with diabetes mellitus. Cystitis, ascending infections leading to pyelonephritis, emphysematous complications and renal and perinephric abscesses are well recognised in this group of patients especially if glycaemic control is poor. Despite the clinical significance of UTI in diabetes, it is inadequately understood and management regimens are mostly not evidence based. Anticipation of potential complications and earlier interventions are vital to reduce serious adverse outcomes. Herein we discuss the aetiology, pathogenesis and management of UTI and its local and more remote complications.
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Affiliation(s)
- Lukman M Hakeem
- Department of Infectious Diseases, Victoria Hospital, Kirkcaldy, Fife, UK,
| | | | - Cyril Lafong
- Department of Microbiology, Victoria Hospital, Kirkcaldy, Fife, UK
| | - Khalid S Janjua
- Department of Urology, Victoria Hospital, Kirkcaldy, Fife, UK
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Population variability of the FimH type 1 fimbrial adhesin in Klebsiella pneumoniae. J Bacteriol 2009; 191:1941-50. [PMID: 19151141 DOI: 10.1128/jb.00601-08] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
FimH is an adhesive subunit of type 1 fimbriae expressed by different enterobacterial species. The enteric bacterium Klebsiella pneumoniae is an environmental organism that is also a frequent cause of sepsis, urinary tract infection (UTI), and liver abscess. Type 1 fimbriae have been shown to be critical for the ability of K. pneumoniae to cause UTI in a murine model. We show here that the K. pneumoniae fimH gene is found in 90% of strains from various environmental and clinical sources. The fimH alleles exhibit relatively low nucleotide and structural diversity but are prone to frequent horizontal-transfer events between different bacterial clones. Addition of the fimH locus to multiple-locus sequence typing significantly improved the resolution of the clonal structure of pathogenic strains, including the K1 encapsulated liver isolates. In addition, the K. pneumoniae FimH protein is targeted by adaptive point mutations, though not to the same extent as FimH from uropathogenic Escherichia coli or TonB from the same K. pneumoniae strains. Such adaptive mutations include a single amino acid deletion from the signal peptide that might affect the length of the fimbrial rod by affecting FimH translocation into the periplasm. Another FimH mutation (S62A) occurred in the course of endemic circulation of a nosocomial uropathogenic clone of K. pneumoniae. This mutation is identical to one found in a highly virulent uropathogenic strain of E. coli, suggesting that the FimH mutations are pathoadaptive in nature. Considering the abundance of type 1 fimbriae in Enterobacteriaceae, our present finding that fimH genes are subject to adaptive microevolution substantiates the importance of type 1 fimbria-mediated adhesion in K. pneumoniae.
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Thom KA, Shardell MD, Osih RB, Schweizer ML, Furuno JP, Perencevich EN, McGregor JC, Harris AD. Controlling for severity of illness in outcome studies involving infectious diseases: impact of measurement at different time points. Infect Control Hosp Epidemiol 2009; 29:1048-53. [PMID: 18817505 DOI: 10.1086/591453] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Severity of illness is an important confounder in outcome studies involving infectious diseases. However, it is unclear whether the time at which severity of illness is measured is important. METHODS We performed a retrospective study of 328 episodes of gram-negative bacteremia in adult patients to assess the impact of the time of measurement of severity of illness on the association between empirical antimicrobial therapy received and in-hospital mortality. Using a modified Acute Physiology Score (APS), severity of illness was measured at 2 time points: (1) hospital admission and (2) 24 hours before the first culture-positive blood sample was collected. Multivariate logistic regression was used to estimate the impact of adjusting for the APS on the relationship between empirical therapy received (ie, the exposure) and in-hospital mortality (ie, the outcome). RESULTS The mean APS (+/- standard deviation) of patients with bacteremia increased during their hospital stay (from 19.2 +/- 11.6 at admission to 24.2 +/- 13.6 at the second time point; P < .01). When examining the association between empirical antimicrobial therapy received and in-hospital mortality, and controlling for the APS, there was a trend toward a decreased impact of appropriate therapy received on in-hospital mortality. The unadjusted odds ratio (OR) for the association between appropriate therapy received and in-hospital mortality was 0.83 (95% confidence interval [CI], 0.51-1.34). After controlling for the APS at admission, this association was attenuated (OR, 0.94 [95% CI, 0.57-1.55]), and when a change in the APS was also included in the multivariate logistic regression model, the association was further attenuated (OR, 0.99 [95% CI, 0.58-1.69]). CONCLUSIONS The magnitude of the association between appropriate antimicrobial therapy received and in-hospital mortality among patients with gram-negative bacteremia was sensitive to the timing of adjustment for severity of illness.
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Affiliation(s)
- Kerri A Thom
- Department of Epidemiology and Preventive Medicine, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA.
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Chhibber S, Kaur S, Kumari S. Therapeutic potential of bacteriophage in treating Klebsiella pneumoniae B5055-mediated lobar pneumonia in mice. J Med Microbiol 2008; 57:1508-1513. [DOI: 10.1099/jmm.0.2008/002873-0] [Citation(s) in RCA: 128] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Klebsiella pneumoniae causes infections in humans especially in immunocompromised patients. About 80 % of nosocomial infections caused by K. pneumoniae are due to multidrug-resistant strains. The emergence of antibiotic-resistant bacterial strains necessitates the exploration of alternative antibacterial therapies, which led our group to study the ability of bacterial viruses (known as bacteriophages or simply phages) to treat mice challenged with K. pneumoniae. Phage SS specific for K. pneumoniae B5055 was isolated and characterized, and its potential as a therapeutic agent was evaluated in an experimental model of K. pneumoniae-mediated lobar pneumonia in mice. Mice were challenged by intranasal (i.n.) inoculation with bacteria (108 c.f.u. ml−1). A single intraperitoneal injection of 1010 p.f.u. ml−1 phage administered immediately after i.n. challenge was sufficient to rescue 100 % of animals from K. pneumoniae-mediated respiratory infections. Administration of the phage preparation 3 h prior to i.n. bacterial challenge provided significant protection in infected mice, while even 6 h delay of phage administration after the induction of infection rendered the phage treatment ineffective. The results of this study therefore suggest that the timing of starting the phage therapy after initiation of infection significantly contributes towards the success of the treatment.
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Affiliation(s)
- Sanjay Chhibber
- Department of Microbiology, Panjab University, Chandigarh-160014, India
| | - Sandeep Kaur
- Department of Microbiology, Panjab University, Chandigarh-160014, India
| | - Seema Kumari
- Department of Microbiology, Panjab University, Chandigarh-160014, India
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Thom KA, Schweizer ML, Osih RB, McGregor JC, Furuno JP, Perencevich EN, Harris AD. Impact of empiric antimicrobial therapy on outcomes in patients with Escherichia coli and Klebsiella pneumoniae bacteremia: a cohort study. BMC Infect Dis 2008; 8:116. [PMID: 18793400 PMCID: PMC2551598 DOI: 10.1186/1471-2334-8-116] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Accepted: 09/15/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND It is unclear whether appropriate empiric antimicrobial therapy improves outcomes in patients with bacteremia due to Escherichia coli or Klebsiella. The objective of this study is to assess the impact of appropriate empiric antimicrobial therapy on in-hospital mortality and post-infection length of stay in patients with Escherichia coli or Klebsiella bacteremia while adjusting for important confounding variables. METHODS We performed a retrospective cohort study of adult patients with a positive blood culture for E. coli or Klebsiella between January 1, 2001 and June 8, 2005 and compared in-hospital mortality and post-infection length of stay between subjects who received appropriate and inappropriate empiric antimicrobial therapy. Empiric therapy was defined as the receipt of an antimicrobial agent between 8 hours before and 24 hours after the index blood culture was drawn and was considered appropriate if it included antimicrobials to which the specific isolate displayed in vitro susceptibility. Data were collected electronically and through chart review. Survival analysis was used to statistically assess the association between empiric antimicrobial therapy and outcome (mortality or length of stay). Multivariable Cox proportional hazards models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI). RESULTS Among 416 episodes of bacteremia, 305 (73.3%) patients received appropriate empiric antimicrobial therapy. Seventy-one (17%) patients died before discharge from the hospital. The receipt of appropriate antimicrobial agents was more common in hospital survivors than in those who died (p = 0.04). After controlling for confounding variables, there was no association between the receipt of appropriate empiric antimicrobial therapy and in-hospital mortality (HR, 1.03; 95% CI, 0.60 to 1.78). The median post-infection length of stay was 7 days. The receipt of appropriate antimicrobial agents was not associated with shortened post-infection length of stay, even after controlling for confounding (HR, 1.11; 95% CI 0.86 to 1.44). CONCLUSION Appropriate empiric antimicrobial therapy for E. coli and Klebsiella bacteremia is not associated with lower in-hospital mortality or shortened post-infection length of stay. This suggests that the choice of empiric antimicrobial agents may not improve outcomes and also provides data to support a randomized trial to test the hypothesis that use (and overuse) of broad-spectrum antibiotics prior to the availability of culture results is not warranted.
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Affiliation(s)
- Kerri A Thom
- Department of Epidemiology and Preventive Medicine, University of Maryland School of Medicine, Baltimore, MD, USA.
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Abstract
Diabetics have a higher incidence of urinary tract infection (UTI), are infected with a broader range of uropathogens, and more commonly develop serious UTI sequelae than nondiabetics. To better study UTI in the diabetic host, we created and characterized a murine model of diabetic UTI using the pancreatic islet beta-cell toxin streptozocin in C3H/HeN, C3H/HeJ, and C57BL/6 mouse backgrounds. Intraperitoneal injections of streptozocin were used to initiate diabetes in healthy mouse backgrounds, as defined by consecutive blood glucose levels of >250 mg/dl. UTIs caused by uropathogenic Escherichia coli (UTI89), Klebsiella pneumoniae (TOP52 1721), and Enterococcus faecalis (0852) were studied, and diabetic mice were found to be considerably more susceptible to infection. All three uropathogens produced significantly higher bladder and kidney titers than buffer-treated controls. Uropathogens did not have as large an advantage in the Toll-like receptor 4-defective C3H/HeJ diabetic mouse, arguing that the dramatic increase in colonization seen in C3H/HeN diabetic mice may partially be due to diabetic-induced defects in innate immunity. Competition experiments demonstrated that E. coli had a significant advantage over K. pneumoniae in the bladders of healthy mice and less of an advantage in diabetic bladders. In the kidneys, K. pneumoniae outcompeted E. coli in healthy mice but in diabetic mice E. coli outcompeted K. pneumoniae and caused severe pyelonephritis. Diabetic kidneys contained renal tubules laden with communities of E. coli UTI89 bacteria within an extracellular-matrix material. Diabetic mice also had glucosuria, which may enhance bacterial replication in the urinary tract. These data support that this murine diabetic UTI model is consistent with known characteristics of human diabetic UTI and can provide a powerful tool for dissecting this infection in the multifactorial setting of diabetes.
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Utilization of an intracellular bacterial community pathway in Klebsiella pneumoniae urinary tract infection and the effects of FimK on type 1 pilus expression. Infect Immun 2008; 76:3337-45. [PMID: 18411285 DOI: 10.1128/iai.00090-08] [Citation(s) in RCA: 102] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Klebsiella pneumoniae is an important cause of urinary tract infection (UTI), but little is known about its pathogenesis in vivo. The pathogenesis of the K. pneumoniae cystitis isolate TOP52 was compared to that of the uropathogenic Escherichia coli (UPEC) isolate UTI89 in a murine cystitis model. Bladder and kidney titers of TOP52 were lower than those of UTI89 at early time points but similar at later time points. TOP52, like UTI89, formed biofilm-like intracellular bacterial communities (IBCs) within the murine bladder, albeit at significantly lower levels than UTI89. Additionally, filamentation of TOP52 was observed, a process critical for UTI89 evasion of neutrophil phagocytosis and persistence in the bladder. Thus, the IBC pathway is not specific to UPEC alone. We investigated if differences in type 1 pilus expression may explain TOP52's early defect in vivo. The type 1 pilus operon is controlled by recombinase-mediated (fimE, fimB, and fimX) phase variation of an invertible promoter element. We found that K. pneumoniae carries an extra gene of unknown function at the 3' end of its type 1 operon, fimK, and the genome lacks the recombinase fimX. A deletion mutant of fimK was constructed, and TOP52 Delta fimK had higher titers and formed more IBCs in the murine cystitis model than wild type. The loss of fimK or expression of E. coli fimX from a plasmid in TOP52 resulted in a larger phase-ON population and higher expression levels of type 1 pili and gave TOP52 the ability to form type 1-dependent biofilms. Complementation with pfimK decreased type 1 pilus expression and biofilm formation of TOP52 Delta fimK and decreased UTI89 biofilm formation. Thus, K. pneumoniae appears programmed for minimal expression of type 1 pili, which may explain, in part, why K. pneumoniae is a less prevalent etiologic agent of UTI than UPEC.
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Søgaard M, Hansen DS, Fiandaca MJ, Stender H, Schønheyder HC. Peptide nucleic acid fluorescence in situ hybridization for rapid detection of Klebsiella pneumoniae from positive blood cultures. J Med Microbiol 2007; 56:914-917. [PMID: 17577055 DOI: 10.1099/jmm.0.46829-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This study evaluated a novel peptide nucleic acid (PNA) probe targeting a region of the 23S rRNA gene of Klebsiella pneumoniae by fluorescence in situ hybridization (FISH). Analytical performance was determined using 39 reference strains and other well-characterized strains of Klebsiella spp. and Enterobacter aerogenes. The probe was found to be specific for the K. pneumoniae complex (K. pneumoniae including Klebsiella ozaenae and Klebsiella variicola). The diagnostic accuracy was evaluated with 264 blood cultures containing Gram-negative rods. Using conventional identification as the reference, performance specifications were as follows: sensitivity 98.8 %, specificity 99.5 %, positive predictive value 98.8 % and negative predictive value 99.5 %. Discrepancies were resolved by PNA FISH retest and phenotypic tests. In conclusion, the K. pneumoniae probe provided an accurate diagnosis within 3 h and may supplement other methods for direct identification of Gram-negative bacteria.
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Affiliation(s)
- Mette Søgaard
- Department of Clinical Epidemiology, Aalborg Hospital, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Microbiology, Aalborg Hospital, Aarhus University Hospital, Postbox 365, 9100 Aalborg, Denmark
| | - Dennis S Hansen
- Department of Clinical Microbiology, Hillerød Sygehus, Denmark
- The International Escherichia and Klebsiella Reference Center (WHO), Statens Serum Institut, Copenhagen, Denmark
| | | | | | - Henrik C Schønheyder
- Department of Clinical Microbiology, Aalborg Hospital, Aarhus University Hospital, Postbox 365, 9100 Aalborg, Denmark
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Thomsen RW, Jepsen P, Sørensen HT. Diabetes mellitus and pyogenic liver abscess: risk and prognosis. Clin Infect Dis 2007; 44:1194-201. [PMID: 17407038 DOI: 10.1086/513201] [Citation(s) in RCA: 112] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2006] [Accepted: 01/10/2007] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Pyogenic liver abscess (PLA) is a rare, life-threatening disease with an increasing rate of incidence. Case reports from East Asia suggest that diabetes mellitus is an important risk factor, but formal evidence is limited. METHODS We performed a case-control study with participants drawn from the entire population of Denmark. Cases of PLA were defined as occurring in all patients who received a first-time diagnosis of PLA on hospital discharge between 1977 and 2002, as identified in the nationwide Danish National Patient Registry. Fifty sex- and age-matched population control subjects were selected for each patient with PLA. We computed the relative risk of PLA associated with diabetes using conditional logistic regression and controlling for major potential confounders. We further examined whether diabetes increased the relative risk of death until 30 days after hospital discharge among patients with PLA. RESULTS We identified 1448 patients who experienced a first hospitalization for PLA during the study period (median age, 64 years; male sex, 54.2%). Persons with diabetes had a 3.6-fold increased risk of experiencing PLA, compared with population control subjects (adjusted relative risk, 3.6; 95% confidence interval, 2.9-4.5]. In addition, patients with PLA who had diabetes had a higher 30-day postdischarge mortality rate, compared with patients with PLA who did not have diabetes (24.8% vs. 18.0%). After controlling for other prognostic factors, the relative risk of death for patients with PLA and diabetes was 1.3 (95% confidence interval, 0.9-2.1). CONCLUSIONS Diabetes is a strong, potentially modifiable risk factor for PLA. PLA is associated with a similarly poor prognosis for patients with diabetes and for other patients.
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Affiliation(s)
- Reimar W Thomsen
- Department of Clinical Epidemiology, Aarhus University Hospital, Aalborg, Denmark.
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Abstract
The incidence of diabetes continues to increase dramatically; this incidence is predominantly of the type-2 form which clusters together with other comorbidities of hypertension and lipid abnormalities, to form the metabolic syndrome. These conditions will have an increasing impact on urological practice, with erectile dysfunction, hypogonadism, voiding difficulties and urinary tract infections all more common in these patients. These symptoms might be the initial presentation of previously undiagnosed diabetes and it is important to recognise this condition early to avoid later complications including end-stage renal failure.
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Kang CI, Kim SH, Bang JW, Kim HB, Kim NJ, Kim EC, Oh MD, Choe KW. Community-acquired versus nosocomial Klebsiella pneumoniae bacteremia: clinical features, treatment outcomes, and clinical implication of antimicrobial resistance. J Korean Med Sci 2006; 21:816-22. [PMID: 17043412 PMCID: PMC2721989 DOI: 10.3346/jkms.2006.21.5.816] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We conducted this study to compare clinical features, outcomes, and clinical implication of antimicrobial resistance in Klebsiella pneumoniae bacteremia acquired as community vs. nosocomial infection. A total of 377 patients with K. pneumoniae bacteremia (191 community-acquired and 186 nosocomial) were retrospectively analyzed. Neoplastic diseases (hematologic malignancy and solid tumor, 56%) were the most commonly associated conditions in patients with nosocomial bacteremia, whereas chronic liver disease (35%) and diabetes mellitus (20%) were the most commonly associated conditions in patients with community-acquired bacteremia. Bacteremic liver abscess occurred almost exclusively in patients with community-acquired infection. The overall 30-day mortality was 24% (91/377), and the mortality of nosocomial bacteremia was significantly higher than that of community-acquired bacteremia (32% vs. 16%, p<0.001). Of all community-acquired and nosocomial isolates, 4% and 33%, respectively, were extended-spectrum cephalosporin (ESC)-resistant, and 4% and 21%, respectively, were ciprofloxacin (CIP)-resistant. In nosocomial infections, prior uses of ESC and CIP were found to be independent risk factors for ESC and CIP resistance, respectively. Significant differences were identified between community-acquired and nosocomial K. pneumoniae bacteremia, and the mortality of nosocomial infections was more than twice than that of community-acquired infections. Antimicrobial resistance was a widespread nosocomial problem and also identified in community-acquired infections.
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Affiliation(s)
- Cheol-In Kang
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Sung-Han Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Ji-Whan Bang
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Hong-Bin Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Nam-Joong Kim
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Eui-Chong Kim
- Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Korea
- Clinical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Myoung-don Oh
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
- Clinical Research Institute, Seoul National University Hospital, Seoul, Korea
| | - Kang-Won Choe
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
- Clinical Research Institute, Seoul National University Hospital, Seoul, Korea
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Alves MS, Dias RCDS, de Castro ACD, Riley LW, Moreira BM. Identification of clinical isolates of indole-positive and indole-negative Klebsiella spp. J Clin Microbiol 2006; 44:3640-6. [PMID: 16928968 PMCID: PMC1594763 DOI: 10.1128/jcm.00940-06] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Biochemical methods employed to classify bacterial species have limitations and may have contributed to the taxonomic complexity recently reported for the genus Klebsiella. The objective of the present study was to apply a simple biochemical test panel to classify a collection of human Klebsiella isolates. We found that with only three additional tests, it is possible to place most isolates in a defined species. Analysis of a 512-bp sequence of the rpoB gene was used as the reference. A total of 16 conventional and 4 supplementary tests were used to evaluate 122 recent isolates identified as Klebsiella from 120 patients, isolated at the clinical laboratory of a university hospital in Minas Gerais, Brazil. Of these, 102 (84%) isolates were identified as Klebsiella pneumoniae or Klebsiella variicola, 19 (15%) as Klebsiella oxytoca, and 1 (1%) as Raoultella planticola. Enterobacterial repetitive intergenic consensus-PCR typing revealed a diversity of genotypes. rpoB gene sequencing confirmed the phenotypic identification and detected five K. variicola isolates among the K. pneumoniae/K. variicola group. Three additional tests that include growth at 10 degrees C and histamine and d-melezitose assimilation should be considered essential tests for the typing of Klebsiella isolates.
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Affiliation(s)
- Maria Silvana Alves
- Faculdade de Farmácia e Bioquímica, Universidade Federal de Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil
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Bonadio M, Costarelli S, Morelli G, Tartaglia T. The influence of diabetes mellitus on the spectrum of uropathogens and the antimicrobial resistance in elderly adult patients with urinary tract infection. BMC Infect Dis 2006; 6:54. [PMID: 16545130 PMCID: PMC1434753 DOI: 10.1186/1471-2334-6-54] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2005] [Accepted: 03/17/2006] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND The role of Diabetes mellitus (DM) in the etiology and in the antimicrobial resistance of uropathogens in patients with urinary tract infection has not been well clarified. For this reason we have evaluated the spectrum of uropathogens and the profile of antibiotic resistance in both diabetic and non diabetic patients with asymptomatic urinary tract infection (UTI). METHODS Urinary isolates and their patterns of susceptibility to the antimicrobials were evaluated in 346 diabetics (229 females and 117 males) and 975 non diabetics (679 females and 296 males) who were screened for significant bacteriuria (> or = 10(5) CFU/mL urine). The mean age of diabetic and non diabetic patients was respectively 73.7 yrs +/- 15 S.D. and 72.7 +/- 24 (p = NS). RESULTS Most of our patients had asymptomatic UTI. The most frequent causative organisms of bacteriuria in females with and without DM were respectively : E. coli 54.1% vs 58.2% (p = NS), Enterococcus spp 8.3% vs 6.5% (p = NS), Pseudomonas spp 3.9 vs 4.7% (p = NS). The most frequent organisms in diabetic and non diabetic males were respectively E. coli 32.5% vs 31.4% (p = NS), Enterococcus spp 9.4% vs 14.5% (p = NS), Pseudomonas spp 8.5% vs 17.2% (p < or = 0.02). A similar isolation rate of E. coli, Enterococcus spp and Pseudomonas spp was also observed in patients with indwelling bladder catheter with and without DM. No significant differences in resistance rates to ampicillin, nitrofurantoin, cotrimoxazole and ciprofloxacin of E. coli and Enteroccus spp were observed between diabetic and non diabetic patients. CONCLUSION In our series of patients with asymptomatic UTI (mostly hospital acquired), diabetes mellitus per se does not seem to influence the isolation rate of different uropathogens and their susceptibility patterns to antimicrobials.
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Affiliation(s)
- Mario Bonadio
- Infectious Diseases Section, Department of Medicine, Ospedale S.Chiara, via Roma 56, 56100 Pisa, Italy
| | - Silvia Costarelli
- Infectious Diseases Section, Department of Medicine, Ospedale S.Chiara, via Roma 56, 56100 Pisa, Italy
| | - Giovanna Morelli
- Infectious Diseases Section, Department of Medicine, Ospedale S.Chiara, via Roma 56, 56100 Pisa, Italy
| | - Tiziana Tartaglia
- Infectious Diseases Section, Department of Medicine, Ospedale S.Chiara, via Roma 56, 56100 Pisa, Italy
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42
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Marra AR, Wey SB, Castelo A, Gales AC, Cal RGR, Filho JRDC, Edmond MB, Pereira CAP. Nosocomial bloodstream infections caused by Klebsiella pneumoniae: impact of extended-spectrum beta-lactamase (ESBL) production on clinical outcome in a hospital with high ESBL prevalence. BMC Infect Dis 2006; 6:24. [PMID: 16478537 PMCID: PMC1382232 DOI: 10.1186/1471-2334-6-24] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2005] [Accepted: 02/14/2006] [Indexed: 11/10/2022] Open
Abstract
Background The frequency of ESBL producing Klebsiella pneumoniae bloodstream infections (BSI) is high in Brazilian hospitals, however little is known regarding what role, if any, resistance plays in the expected outcome in hospitals with a high prevalence of these pathogens. Methods From 1996 to 2001, hospital acquired K. pneumoniae BSI were evaluated retrospectively. Each patient was included only once at the time of BSI. ESBL producing strains were identified using the E-test method. The association of variables with the mortality related to bacteremia was included in a stepwise logistic regression model. Results One hundred and eight hospital acquired K. pneumoniae BSI met criteria for inclusion. Fifty two percent were due to ESBL producing strains. The overall in-hospital mortality was 40.8%. Variables independently predicting death by multivariate analysis were the following: mechanical ventilation (p = 0.001), number of comorbidities (p = 0.003), antimicrobials prescribed before bacteremia (p = 0.01) and fatal underlying disease (p = 0.025). Conclusion Bacteremia due to ESBL producing K. pneumoniae strains was not an independent predictor for death in patients with BSI. An increased mortality in hospital-acquired BSI by K. pneumoniae was related to the requirement for mechanical ventilation, more than two comorbidities, the previous use of two or more antibiotics, and the presence of a rapidly fatal disease.
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Affiliation(s)
- Alexandre R Marra
- Division of Infectious Diseases, Universidade Federal de São Paulo, Brasil (UNIFESP-EPM)/Hospital São Paulo (HSP), Brasil
| | - Sérgio B Wey
- Division of Infectious Diseases, Universidade Federal de São Paulo, Brasil (UNIFESP-EPM)/Hospital São Paulo (HSP), Brasil
| | - Adauto Castelo
- Division of Infectious Diseases, Universidade Federal de São Paulo, Brasil (UNIFESP-EPM)/Hospital São Paulo (HSP), Brasil
| | - Ana Cristina Gales
- Division of Infectious Diseases, Universidade Federal de São Paulo, Brasil (UNIFESP-EPM)/Hospital São Paulo (HSP), Brasil
- Clinical Microbiology Laboratory, Universidade Federal de São Paulo, Brasil (UNIFESP-EPM)/Hospital São Paulo (HSP), Brasil
| | | | - José R do Carmo Filho
- Clinical Microbiology Laboratory, Universidade Federal de São Paulo, Brasil (UNIFESP-EPM)/Hospital São Paulo (HSP), Brasil
| | - Michael B Edmond
- Department of Internal Medicine, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond, Virginia, USA
| | - Carlos Alberto P Pereira
- Division of Infectious Diseases, Universidade Federal de São Paulo, Brasil (UNIFESP-EPM)/Hospital São Paulo (HSP), Brasil
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Struve C, Bojer M, Nielsen EM, Hansen DS, Krogfelt KA. Investigation of the putative virulence gene magA in a worldwide collection of 495 Klebsiella isolates: magA is restricted to the gene cluster of Klebsiella pneumoniae capsule serotype K1. J Med Microbiol 2005; 54:1111-1113. [PMID: 16192445 DOI: 10.1099/jmm.0.46165-0] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Carsten Struve
- Unit of Gastrointestinal Infections, Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Copenhagen, Denmark 2The International Escherichia coli and Klebsiella Reference Centre (WHO), Statens Serum Institut, Copenhagen, Denmark
| | - Martin Bojer
- Unit of Gastrointestinal Infections, Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Copenhagen, Denmark 2The International Escherichia coli and Klebsiella Reference Centre (WHO), Statens Serum Institut, Copenhagen, Denmark
| | - Eva Møller Nielsen
- Unit of Gastrointestinal Infections, Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Copenhagen, Denmark 2The International Escherichia coli and Klebsiella Reference Centre (WHO), Statens Serum Institut, Copenhagen, Denmark
| | - Dennis Schrøder Hansen
- Unit of Gastrointestinal Infections, Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Copenhagen, Denmark 2The International Escherichia coli and Klebsiella Reference Centre (WHO), Statens Serum Institut, Copenhagen, Denmark
| | - Karen A Krogfelt
- Unit of Gastrointestinal Infections, Department of Bacteriology, Mycology and Parasitology, Statens Serum Institut, Copenhagen, Denmark 2The International Escherichia coli and Klebsiella Reference Centre (WHO), Statens Serum Institut, Copenhagen, Denmark
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Brown JS, Wessells H, Chancellor MB, Howards SS, Stamm WE, Stapleton AE, Steers WD, Van Den Eeden SK, McVary KT. Urologic complications of diabetes. Diabetes Care 2005; 28:177-85. [PMID: 15616253 DOI: 10.2337/diacare.28.1.177] [Citation(s) in RCA: 192] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Jeanette S Brown
- University of California, San Francisco, San Francisco, California 94115, USA.
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Hansen DS, Aucken HM, Abiola T, Podschun R. Recommended test panel for differentiation of Klebsiella species on the basis of a trilateral interlaboratory evaluation of 18 biochemical tests. J Clin Microbiol 2004; 42:3665-9. [PMID: 15297514 PMCID: PMC497635 DOI: 10.1128/jcm.42.8.3665-3669.2004] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Klebsiella pneumoniae and Klebsiella oxytoca are the two most frequently encountered Klebsiella species giving rise to infections in humans, but other Klebsiella species can also be found in clinical specimens: Klebsiella ozaenae, Klebsiella rhinoscleromatis, Klebsiella terrigena, Klebsiella planticola, Klebsiella ornithinolytica, and Enterobacter aerogenes (Klebsiella mobilis). However, many of these species are indistinguishable by the conventional methods employed routinely in the clinical microbiological laboratory. Several investigators have suggested various additional tests, but as yet there is no standardized test panel for identifying all Klebsiella species and subspecies. In the present study, performed in three national Klebsiella reference laboratories, we have evaluated a test panel consisting of 18 biochemical tests on 242 strains comprising all Klebsiella species and subspecies. The test panel was designed to identify organisms preliminarily identified as belonging to the genus Klebsiella on the basis of conventional methods or automated identification systems. With the described test panel it is possible to find one or more positive test results differentiating any Klebsiella species, except Klebsiella rhinoscleromatis, from its closest relative.
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Affiliation(s)
- Dennis S Hansen
- The International Escherichia and Klebsiella Reference Centre (WHO), Statens Serum Institut, Copenhagen, enmark.
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46
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Abstract
Klebsiella pneumoniae is an important opportunistic pathogen and a frequent cause of nosocomial infections. K. pneumoniae infections can occur at nearly any body site; however, urinary tract infections and infections of the respiratory tract predominate. Infections are frequently preceded by gastrointestinal colonization, and the gastrointestinal tract is believed to be the most important reservoir for transmission of the bacteria. In contrast to many other bacterial pathogens, K. pneumoniae is ubiquitous in nature. Several studies have described Klebsiella isolates of environmental origin to be nearly identical to clinical isolates with respect to several phenotypic properties. However, the pathogenic potential of environmental K. pneumoniae isolates is essentially unknown. We have evaluated the virulence of K. pneumoniae strains of environmental and clinical origin directly in animal models, i.e. in urinary tract infection and intestinal colonization models. Furthermore, the ability to adhere to and invade human epithelial cell lines was examined. Although strain-to-strain differences were observed in the individual infection models, overall, strains of environmental origin were found to be as virulent as strains of clinical origin. The ubiquity of K. pneumoniae in nature and the general ability of K. pneumoniae strains to infect susceptible hosts might explain the high frequency of opportunistic infections caused by this species.
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Affiliation(s)
- Carsten Struve
- Department of Gastrointestinal and Parasitic Infections, Statens Serum Institut, Artillerivej 5, 2300 Copenhagen S, Denmark
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47
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Regué M, Hita B, Piqué N, Izquierdo L, Merino S, Fresno S, Benedí VJ, Tomás JM. A gene, uge, is essential for Klebsiella pneumoniae virulence. Infect Immun 2004; 72:54-61. [PMID: 14688080 PMCID: PMC343961 DOI: 10.1128/iai.72.1.54-61.2004] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Klebsiella pneumoniae strains typically express both smooth lipopolysaccharide (LPS) with O antigen molecules and capsule polysaccharide (K antigen) on the surface. A single mutation in a gene that codes for a UDP galacturonate 4-epimerase (uge) renders a strain with the O-:K- phenotype (lack of capsule and LPS without O antigen molecules and outer core oligosaccharide). The uge gene was present in all the K. pneumoniae strains tested. The K. pneumoniae uge mutants were unable to produce experimental urinary tract infections in rats and were completely avirulent in two different animal models (septicemia and pneumonia). Reintroduction of the single uge wild-type gene in the corresponding mutants completely restored the wild-type phenotype (presence of capsule and smooth LPS) independently of the O or K serotype of the wild type. Furthermore, complemented uge mutants recovered the ability to produce experimental urinary tract infections in rats and virulence in the septicemia and pneumonia animal models.
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Affiliation(s)
- Miguel Regué
- Departamento de Microbiología, Facultad de Biología, Universidad de Barcelona, 08071 Barcelona, Spain
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48
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Koczura R, Kaznowski A. Occurrence of the Yersinia high-pathogenicity island and iron uptake systems in clinical isolates of Klebsiella pneumoniae. Microb Pathog 2003; 35:197-202. [PMID: 14521878 DOI: 10.1016/s0882-4010(03)00125-6] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ability to acquire iron is crucial to bacteria during an infection. Thirty-four strains of Klebsiella pneumoniae isolated from clinical specimens were examined for the use of various strategies to obtain iron. The isolates employed several iron uptake mechanisms, including production of enterobactin (100%) and aerobactin (50%). Few isolates (18%) produced yersiniabactin, a siderophore encoded by the Yersinia high-pathogenicity island (HPI) despite genetic diversity of the HPI. Majority of the isolates used human transferrin (74%), lactoferrin (97%), hemoglobin (74%), and hemoglobin-haptoglobin complex (56%) as a sole source of iron. Multiple iron uptake systems may be of benefit to the bacteria during infection.
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Affiliation(s)
- Ryszard Koczura
- Department of Microbiology, Institute of Experimental Biology, Adam Mickiewicz University, ul. Fredry 10, Poznań 61-701, Poland.
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49
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Infections urinaires nosocomiales chez l’immunocompétent en milieu médical : qui traiter, quand traiter et comment traiter ? Med Mal Infect 2003. [DOI: 10.1016/s0399-077x(03)00176-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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50
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An evaluation of street-vended sliced papaya (Carica papaya) for bacteria and indicator micro-organisms of public health significance. Food Microbiol 2002. [DOI: 10.1006/fmic.2002.0511] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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