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Westbrook KJ, Chilambi GS, Stellfox ME, Nordstrom HR, Li Y, Iovleva A, Shah NH, Jones CE, Kline EG, Squires KM, Miller WR, Tran TT, Arias CA, Doi Y, Shields RK, Van Tyne D. Differential in vitro susceptibility to ampicillin/ceftriaxone combination therapy among Enterococcus faecalis infective endocarditis clinical isolates. J Antimicrob Chemother 2024; 79:801-809. [PMID: 38334390 PMCID: PMC10984950 DOI: 10.1093/jac/dkae032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Accepted: 01/22/2024] [Indexed: 02/10/2024] Open
Abstract
OBJECTIVES To investigate the genomic diversity and β-lactam susceptibilities of Enterococcus faecalis collected from patients with infective endocarditis (IE). METHODS We collected 60 contemporary E. faecalis isolates from definite or probable IE cases identified between 2018 and 2021 at the University of Pittsburgh Medical Center. We used whole-genome sequencing to study bacterial genomic diversity and employed antibiotic checkerboard assays and a one-compartment pharmacokinetic-pharmacodynamic (PK/PD) model to investigate bacterial susceptibility to ampicillin and ceftriaxone both alone and in combination. RESULTS Genetically diverse E. faecalis were collected, however, isolates belonging to two STs, ST6 and ST179, were collected from 21/60 (35%) IE patients. All ST6 isolates encoded a previously described mutation upstream of penicillin-binding protein 4 (pbp4) that is associated with pbp4 overexpression. ST6 isolates had higher ceftriaxone MICs and higher fractional inhibitory concentration index values for ampicillin and ceftriaxone (AC) compared to other isolates, suggesting diminished in vitro AC synergy against this lineage. Introduction of the pbp4 upstream mutation found among ST6 isolates caused increased ceftriaxone resistance in a laboratory E. faecalis isolate. PK/PD testing showed that a representative ST6 isolate exhibited attenuated efficacy of AC combination therapy at humanized antibiotic exposures. CONCLUSIONS We find evidence for diminished in vitro AC activity among a subset of E. faecalis IE isolates with increased pbp4 expression. These findings suggest that alternate antibiotic combinations against diverse contemporary E. faecalis IE isolates should be evaluated.
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Affiliation(s)
- Kevin J Westbrook
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Gayatri Shankar Chilambi
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Madison E Stellfox
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Hayley R Nordstrom
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Yanhong Li
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Tsinghua University School of Medicine, Beijing, China
| | - Alina Iovleva
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Niyati H Shah
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Chelsea E Jones
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Ellen G Kline
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kevin M Squires
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - William R Miller
- Division of Infectious Diseases, Houston Methodist Hospital, Houston, TX, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, TX, USA
| | - Truc T Tran
- Division of Infectious Diseases, Houston Methodist Hospital, Houston, TX, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, TX, USA
| | - Cesar A Arias
- Division of Infectious Diseases, Houston Methodist Hospital, Houston, TX, USA
- Center for Infectious Diseases, Houston Methodist Research Institute, Houston, TX, USA
- Department of Medicine, Weill Cornell Medical College, New York, NewYork, USA
| | - Yohei Doi
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Ryan K Shields
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Daria Van Tyne
- Division of Infectious Diseases, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Center for Evolutionary Biology and Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Rogers TM, Kline EG, Griffith MP, Jones CE, Rubio AM, Squires KM, Shields RK. Mutations in ompK36 differentially impact in vitro synergy of meropenem/vaborbactam and ceftazidime/avibactam in combination with other antibiotics against KPC-producing Klebsiella pneumoniae. JAC Antimicrob Resist 2023; 5:dlad113. [PMID: 37901589 PMCID: PMC10600568 DOI: 10.1093/jacamr/dlad113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 10/01/2023] [Indexed: 10/31/2023] Open
Abstract
Objectives Ceftazidime/avibactam and meropenem/vaborbactam are preferred agents for Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-Kp) infections and are often used in combination with other agents. We aimed to characterize the synergy of combinations against KPC-Kp with varying ompK36 genotypes. Methods KPC-Kp that harboured ompK36 WT, IS5 or glycine-aspartic acid duplication (GD) genotypes were selected. MICs were determined in triplicate. Synergy was assessed by time-kill assays for ceftazidime/avibactam and meropenem/vaborbactam in combination with colistin, gentamicin, tigecycline, meropenem or fosfomycin against 1 × 108 cfu/mL KPC-Kp. Results KPC-Kp harboured ompK36 WT (n = 5), IS5 (n = 5) or GD (n = 5); 11 were KPC-2 and 4 were KPC-3. All were susceptible to ceftazidime/avibactam and meropenem/vaborbactam. In time-kill analysis, ceftazidime/avibactam and meropenem/vaborbactam 1 × MIC exhibited mean 24 h log-kills of -2.01 and -0.84, respectively. Ceftazidime/avibactam was synergistic in combination with colistin independent of ompK36 genotype. Ceftazidime/avibactam combinations impacted by porin mutations (compared to WT) were meropenem (-5.18 versus -6.62 mean log-kill, P < 0.001) and fosfomycin (-3.98 versus -6.58, P = 0.058). Mean log-kills with meropenem/vaborbactam were greatest in combination with gentamicin (-5.36). In the presence of porin mutations, meropenem/vaborbactam killing activity was potentiated by the addition of colistin (-6.65 versus -0.70, P = 0.03) and fosfomycin (-3.12 versus 1.54, P = 0.003). Conclusions Our results shed new light on the synergy of ceftazidime/avibactam and meropenem/vaborbactam combinations against KPC-Kp with or without porin mutations. Killing activity of ceftazidime/avibactam with other cell wall active agents was decreased against isolates with porin mutations. On the other hand, some meropenem/vaborbactam combinations demonstrated enhanced killing in the presence of porin mutations.
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Affiliation(s)
- Tara M Rogers
- School of Pharmacy, University of Pittsburgh, Pittsburgh, PA, USA
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA, USA
| | - Ellen G Kline
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA, USA
| | - Marissa P Griffith
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA, USA
| | - Chelsea E Jones
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA, USA
| | - Abigail M Rubio
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA, USA
| | - Kevin M Squires
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA, USA
| | - Ryan K Shields
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA, USA
- Center for Innovative Antimicrobial Therapy, University of Pittsburgh, Pittsburgh, PA, USA
- Antibiotic Management Program, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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Shields RK, Kline EG, Squires KM, Van Tyne D, Doi Y. In vitro activity of cefiderocol against Pseudomonas aeruginosa demonstrating evolved resistance to novel β-lactam/β-lactamase inhibitors. JAC Antimicrob Resist 2023; 5:dlad107. [PMID: 37795425 PMCID: PMC10546814 DOI: 10.1093/jacamr/dlad107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Accepted: 09/14/2023] [Indexed: 10/06/2023] Open
Abstract
Background Cefiderocol demonstrates excellent activity against MDR Pseudomonas aeruginosa; however, the activity against isolates from patients previously treated with β-lactam agents is unknown. We aimed to determine the activity of cefiderocol against P. aeruginosa collected before and after treatment with traditional β-lactams and new β-lactam/β-lactamase inhibitors. Methods Cefiderocol MICs were determined in triplicate in iron-depleted cation-adjusted Mueller-Hinton broth and compared with β-lactam MICs tested by standard methods. All isolates underwent WGS analysis to identify mutations associated with resistance. Results One hundred and seventy-eight P. aeruginosa isolates were evaluated; 48% (86/178) were non-susceptible to ceftazidime/avibactam, ceftolozane/tazobactam and/or imipenem/relebactam. The cefiderocol MIC50 and MIC90 were 0.12 and 1 mg/L, respectively. Median cefiderocol MICs did not vary against isolates classified as MDR, XDR, or those non-susceptible to ceftazidime/avibactam, ceftolozane/tazobactam and/or imipenem/relebactam when compared with non-MDR isolates. Against isolates collected from patients previously treated with ceftolozane/tazobactam, cefiderocol MICs were increased 4-fold compared with baseline. Cross-resistance to cefiderocol was identified in 21% (3/14) of patients who developed treatment-emergent resistance to ceftolozane/tazobactam. Overall, 6% (11/178) of isolates demonstrated cefiderocol MICs ≥2 mg/L, which were disproportionately collected from patients previously treated with ceftolozane/tazobactam (73%; 8/11). Isolates with reduced cefiderocol susceptibility harboured mutations in ampC, tonB-dependent receptors, the response regulator pirR and ftsI. Conclusions Cefiderocol demonstrates excellent in vitro activity against P. aeruginosa isolates exposed to other novel β-lactam agents; however, some exceptions were identified. Cross-resistance between cefiderocol and ceftolozane/tazobactam was evident, but not with ceftazidime/avibactam or imipenem/relebactam. Reduced cefiderocol susceptibility was mediated by mutations in ampC and tonB-dependent receptors.
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Affiliation(s)
- Ryan K Shields
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Innovative Antimicrobial Therapy, University of Pittsburgh, Pittsburgh, PA, USA
- Antibiotic Management Program, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Ellen G Kline
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Kevin M Squires
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Daria Van Tyne
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Innovative Antimicrobial Therapy, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Evolutionary Biology and Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yohei Doi
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Innovative Antimicrobial Therapy, University of Pittsburgh, Pittsburgh, PA, USA
- Departments of Microbiology and Infectious Diseases, Fujita Health University School of Medicine, Toyoake, Aichi, Japan
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Heil EL, Claeys KC, Kline EG, Rogers TM, Squires KM, Iovleva A, Doi Y, Banoub M, Noval MM, Luethy PM, Shields RK. Early initiation of three-drug combinations for the treatment of carbapenem-resistant A. baumannii among COVID-19 patients. J Antimicrob Chemother 2023; 78:1034-1040. [PMID: 36869724 PMCID: PMC10319978 DOI: 10.1093/jac/dkad042] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Accepted: 02/06/2023] [Indexed: 03/05/2023] Open
Abstract
OBJECTIVES We evaluated the clinical characteristics and outcomes of patients with COVID-19 who received three-drug combination regimens for treatment of carbapenem-resistant Acinetobacter baumannii (CRAB) infections during a single-centre outbreak. Our objective was to describe the clinical outcomes and molecular characteristics and in vitro synergy of antibiotics against CRAB isolates. MATERIALS AND METHODS Patients with severe COVID-19 admitted between April and July 2020 with CRAB infections were retrospectively evaluated. Clinical success was defined as resolution of signs/symptoms of infection without need for additional antibiotics. Representative isolates underwent whole-genome sequencing (WGS) and in vitro synergy of two- or three-drug combinations was assessed by checkerboard and time-kill assays, respectively. RESULTS Eighteen patients with CRAB pneumonia or bacteraemia were included. Treatment regimens included high-dose ampicillin-sulbactam, meropenem, plus polymyxin B (SUL/MEM/PMB; 72%), SUL/PMB plus minocycline (MIN; 17%) or other combinations (12%). Clinical resolution was achieved in 50% of patients and 30-day mortality was 22% (4/18). Seven patients had recurrent infections, during which further antimicrobial resistance to SUL or PMB was not evident. PMB/SUL was the most active two-drug combination by checkerboard. Paired isolates collected before and after treatment with SUL/MEM/PMB did not demonstrate new gene mutations or differences in the activity of two- or three-drug combinations. CONCLUSIONS Use of three-drug regimens for severe CRAB infections among COVID-19 resulted in high rates of clinical response and low mortality relative to previous studies. The emergence of further antibiotic resistance was not detected phenotypically or through WGS analysis. Additional studies are needed to elucidate preferred antibiotic combinations linked to the molecular characteristics of infecting strains.
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Affiliation(s)
- Emily L Heil
- Department of Practice, Science, and Health Outcomes Research, University of Maryland School of Pharmacy, 20 North Pine Street, Baltimore, MD, USA
| | - Kimberly C Claeys
- Department of Practice, Science, and Health Outcomes Research, University of Maryland School of Pharmacy, 20 North Pine Street, Baltimore, MD, USA
| | - Ellen G Kline
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Tara M Rogers
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Kevin M Squires
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Alina Iovleva
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yohei Doi
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Mary Banoub
- Department of Pharmacy, University of Maryland Medical Center, Baltimore, MD, USA
| | - Mandee M Noval
- Department of Pharmacy, University of Maryland Medical Center, Baltimore, MD, USA
| | - Paul M Luethy
- Department of Pathology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Ryan K Shields
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
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Rogers TM, Kline EG, Griffith MP, Jones CE, Rubio AM, Squires KM, Shields RK. Impact of ompk36 genotype and KPC subtype on the in vitro activity of ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam against KPC-producing K. pneumoniae clinical isolates. JAC Antimicrob Resist 2023; 5:dlad022. [PMID: 36968951 PMCID: PMC10035640 DOI: 10.1093/jacamr/dlad022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 02/14/2023] [Indexed: 03/25/2023] Open
Abstract
Objectives The availability of new β-lactam/β-lactamase inhibitors ceftazidime/avibactam, meropenem/vaborbactam and imipenem/relebactam have redefined contemporary treatment of Klebsiella pneumoniae carbapenemase-producing Klebsiella pneumoniae (KPC-Kp) infections. We aimed to characterize and contrast the in vitro activity of these agents against genetically diverse KPC-Kp clinical isolates. Methods We analysed genomes of 104 non-consecutive KPC-Kp isolates and compared the in vitro antibiotic activity by KPC subtype and ompK36 genotype. MICs were determined in triplicate by CLSI methods. Twenty representative isolates were selected for time–kill analyses against physiological steady-state and trough concentrations, as well as 4× MIC for each agent. Results Fifty-eight percent and 42% of isolates harboured KPC-2 and KPC-3, respectively. OmpK36 mutations were more common among KPC-2- compared with KPC-3-producing Kp (P < 0.0001); mutations were classified as IS5 insertion, glycine-aspartic acid insertion at position 134 (GD duplication) and other mutations. Compared to isolates with WT ompK36, ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam MICs were elevated for isolates with IS5 by 2-, 4- and 16-fold, respectively (P < 0.05 for each). Against isolates with GD duplication, imipenem/relebactam and meropenem/vaborbactam MICs were increased, but ceftazidime/avibactam MICs were not. In time–kill studies, ceftazidime/avibactam-mediated killing correlated with ceftazidime/avibactam MICs, and did not vary across ompK36 genotypes. Imipenem/relebactam was not bactericidal against any isolate at trough concentrations. At steady-state imipenem/relebactam concentrations, regrowth occurred more commonly for isolates with IS5 mutations. Log-kills were lower in the presence of meropenem/vaborbactam for isolates with GD duplication compared with IS5 mutations. Conclusions Our investigation identified key genotypes that attenuate, to varying degrees, the in vitro activity for each of the new β-lactam/β-lactamase inhibitors. Additional studies are needed to translate the importance of these observations into clinical practice.
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Affiliation(s)
- Tara M Rogers
- School of Pharmacy, University of Pittsburgh, Pittsburgh, PA, USA
| | - Ellen G Kline
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA 15213, USA
| | - Marissa P Griffith
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA 15213, USA
| | - Chelsea E Jones
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA 15213, USA
| | - Abigail M Rubio
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA 15213, USA
| | - Kevin M Squires
- Department of Medicine, University of Pittsburgh, 3601 Fifth Avenue, Falk Medical Building, Suite 5B, Pittsburgh, PA 15213, USA
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Cheng S, Fleres G, Chen L, Liu G, Hao B, Newbrough A, Driscoll E, Shields RK, Squires KM, Chu TY, Kreiswirth BN, Nguyen MH, Clancy CJ. Within-Host Genotypic and Phenotypic Diversity of Contemporaneous Carbapenem-Resistant Klebsiella pneumoniae from Blood Cultures of Patients with Bacteremia. mBio 2022; 13:e0290622. [PMID: 36445082 PMCID: PMC9765435 DOI: 10.1128/mbio.02906-22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2022] [Accepted: 10/24/2022] [Indexed: 12/02/2022] Open
Abstract
It is unknown whether bacterial bloodstream infections (BSIs) are commonly caused by single organisms or mixed microbial populations. We hypothesized that contemporaneous carbapenem-resistant Klebsiella pneumoniae (CRKP) strains from blood cultures of individual patients are genetically and phenotypically distinct. We determined short-read whole-genome sequences of 10 sequence type 258 (ST258) CRKP strains from blood cultures in each of 6 patients (Illumina HiSeq). Strains clustered by patient by core genome and pan-genome phylogeny. In 5 patients, there was within-host strain diversity by gene mutations, presence/absence of antibiotic resistance or virulence genes, and/or plasmid content. Accessory gene phylogeny revealed strain diversity in all 6 patients. Strains from 3 patients underwent long-read sequencing for genome completion (Oxford Nanopore) and phenotypic testing. Genetically distinct strains within individuals exhibited significant differences in carbapenem and other antibiotic responses, capsular polysaccharide (CPS) production, mucoviscosity, and/or serum killing. In 2 patients, strains differed significantly in virulence during mouse BSIs. Genetic or phenotypic diversity was not observed among strains recovered from blood culture bottles seeded with index strains from the 3 patients and incubated in vitro at 37°C. In conclusion, we identified genotypic and phenotypic variant ST258 CRKP strains from blood cultures of individual patients with BSIs, which were not detected by the clinical laboratory or in seeded blood cultures. The data suggest a new paradigm of CRKP population diversity during BSIs, at least in some patients. If validated for BSIs caused by other bacteria, within-host microbial diversity may have implications for medical, microbiology, and infection prevention practices and for understanding antibiotic resistance and pathogenesis. IMPORTANCE The long-standing paradigm for pathogenesis of bacteremia is that, in most cases, a single organism passes through a bottleneck and establishes itself in the bloodstream (single-organism hypothesis). In keeping with this paradigm, standard practice in processing positive microbiologic cultures is to test single bacterial strains from morphologically distinct colonies. This study is the first genome-wide analysis of within-host diversity of Klebsiella pneumoniae strains recovered from individual patients with bloodstream infections (BSIs). Our finding that positive blood cultures comprised genetically and phenotypically heterogeneous carbapenem-resistant K. pneumoniae strains challenges the single-organism hypothesis and suggests that at least some BSIs are caused by mixed bacterial populations that are unrecognized by the clinical laboratory. The data support a model of pathogenesis in which pressures in vivo select for strain variants with particular antibiotic resistance or virulence attributes and raise questions about laboratory protocols and treatment decisions directed against single strains.
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Affiliation(s)
- Shaoji Cheng
- University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | | | - Liang Chen
- Hackensack Meridian Health Center for Discovery and Innovation, Nutley, New Jersey, USA
| | - Guojun Liu
- University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Binghua Hao
- University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | | | | | - Ryan K. Shields
- University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | | | - Ting-yu Chu
- Hackensack Meridian Health Center for Discovery and Innovation, Nutley, New Jersey, USA
| | - Barry N. Kreiswirth
- Hackensack Meridian Health Center for Discovery and Innovation, Nutley, New Jersey, USA
| | - M. Hong Nguyen
- University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Cornelius J. Clancy
- University of Pittsburgh, Pittsburgh, Pennsylvania, USA
- VA Pittsburgh Healthcare System, Pittsburgh, Pennsylvania, USA
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