Co-occurrence of Plasmid-Mediated Tigecycline and Carbapenem Resistance in Acinetobacter spp. from Waterfowls and Their Neighboring Environment

ABSTRACT Tigecycline serves as one of the antibiotics of last resort to treat multidrug-resistant (including carbapenem-resistant) pathogens. However, the recently emerged plasmid-mediated tigecycline resistance mechanism, Tet(X), challenges the clinical efficacy of this class of antibiotics. In this study, we detected 180 tet(X)-harboring Acinetobacter isolates (8.9%, n = 180) from 2,018 samples collected from avian farms and adjacent environments in China. Eighteen tet(X)-harboring isolates (10.0%) were found to cocarry the carbapenemase gene blaNDM-1, mostly from waterfowl samples (94.4%, 17/18). Interestingly, among six Acinetobacter strains, tet(X) and blaNDM-1 were found to colocalize on the same plasmids. Moreover, whole-genome sequencing (WGS) revealed a novel orthologue of tet(X) in the six isolates coharboring tet(X) and blaNDM-1. Inverse PCR suggested that the two tet(X) genes form a single transposable unit and may be cotransferred. Sequence comparison between six tet(X)- and blaNDM-1-coharboring plasmids showed that they shared a highly homologous plasmid backbone even though they were isolated from different Acinetobacter species (three from Acinetobacter indicus, two from Acinetobacter schindleri, and one from Acinetobacter lwoffii) from various sources and from different geological regions, suggesting the horizontal genetic transfer of a common tet(X)- and blaNDM-1-coharboring plasmid among Acinetobacter species in China. Emergence and spread of such plasmids and strains are of great clinical concern, and measures must be implemented to avoid their dissemination.

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Informing Antibiotic Treatment Decisions: Evaluating Rapid Molecular Diagnostics To Identify Susceptibility and Resistance to Carbapenems against Acinetobacter spp. in PRIMERS III

Journal of Clinical Microbiology ◽

10.1128/jcm.01524-16 ◽

2016 ◽

Vol 55 (1) ◽

pp. 134-144 ◽

Cited By ~ 16

Author(s):

Scott R. Evans ◽

Andrea M. Hujer ◽

Hongyu Jiang ◽

Carol B. Hill ◽

Kristine M. Hujer ◽

...

Keyword(s):

Molecular Diagnostics ◽

Carbapenem Resistance ◽

Multidrug Resistant ◽

Ionization Mass ◽

Predictive Values ◽

Content Type ◽

Esi Ms ◽

Carbapenem Resistant ◽

Acinetobacter Spp ◽

Susceptibility And Resistance

ABSTRACT The widespread dissemination of carbapenem-resistant Acinetobacter spp. has created significant therapeutic challenges. At present, rapid molecular diagnostics (RMDs) that can identify this phenotype are not commercially available. Two RMD platforms, PCR combined with electrospray ionization mass spectrometry (PCR/ESI-MS) and molecular beacons (MB), for detecting genes conferring resistance/susceptibility to carbapenems in Acinetobacter spp. were evaluated. An archived collection of 200 clinical Acinetobacter sp. isolates was tested. Predictive values for susceptibility and resistance were estimated as a function of susceptibility prevalence and were based on the absence or presence of beta-lactamase ( bla ) NDM, VIM, IMP, KPC, and OXA carbapenemase genes (e.g., bla OXA-23 , bla OXA-24/40 , and bla OXA-58 found in this study) against the reference standard of MIC determinations. According to the interpretation of MICs, 49% ( n = 98) of the isolates were carbapenem resistant (as defined by either resistance or intermediate resistance to imipenem). The susceptibility sensitivities (95% confidence interval [CI]) for imipenem were 82% (74%, 89%) and 92% (85%, 97%) for PCR/ESI-MS and MB, respectively. Resistance sensitivities (95% CI) for imipenem were 95% (88%, 98%) and 88% (80%, 94%) for PCR/ESI-MS and MB, respectively. PRIMERS III establishes that RMDs can discriminate between carbapenem resistance and susceptibility in Acinetobacter spp. In the context of a known prevalence of resistance, SPVs and RPVs can inform clinicians regarding the best choice for empiric antimicrobial therapy against this multidrug-resistant pathogen.

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Genotypic Characterisation of Multi Drug Resistant Gram-Negative Bacteria with Special Reference to Carbapenem Resistance in a Teaching Hospital, Hyderabad, Telangana State

Journal of Evolution of Medical and Dental Sciences ◽

10.14260/jemds/2021/222 ◽

2021 ◽

Vol 10 (14) ◽

pp. 1039-1041

Author(s):

Swathi Gurajala ◽

Sandeep Kumar Tipparthi ◽

Rajkumar H.R.V.

Keyword(s):

Carbapenem Resistance ◽

Multidrug Resistant ◽

Control Measures ◽

Infection Prevention And Control ◽

Resistant Bacteria ◽

Antimicrobial Drug Resistance ◽

Carbapenem Resistant ◽

Carbapenemase Gene ◽

Prevention And Control Measures ◽

And Control

Bacteria develop antimicrobial drug resistance through several mechanisms, the common one being the production of enzymes. As the number of antibiotics discovered is in notable numbers in the past few years, it is important to preserve high-end antibiotics for the treatment of multidrug-resistant organisms (MDROs) infections, by appropriate use of antibiotics. A study was conducted to record prevalence, phenotypic and genotypic characters of MDROs in our hospital, with reference to carbapenem resistance. 200 multidrug-resistant clinical isolates were collected in 6 months. Carbapenem-resistant organisms were detected phenotypically confirmed for the production of carbapenemases by modified Hodge test (MHT) and genotypic detection was done by a multiplex polymerase chain reaction (PCR) assay for the five most predominant carbapenemases (bla NDM-1, bla OXA-48 , bla VIM, bla IMP, bla KPC). The isolates consisted of E. coli (53 %) followed by K. pneumoniae (30 %), P. aeruginosa (13 %), and acinetobacter spp (4 %). Among these, 40 (20 %) isolates were carbapenem-resistant. Of these 40, 27 (67.5 %) showed an increase in zone size by the MHT, suggestive of metallo-beta-lactamase (MBL) mediated carbapenem resistance and about 32 (80 %) isolates were found to contain at least one carbapenemase gene. bla NDM-1 accounted for 37.5 % (12 / 32) of the isolates and was the most predominant one followed by bla OXA-48 [28 % (9 / 32)]. 22 % (7 / 32) of the isolates had one or more carbapenemase genes. Identifying the mechanisms of resistance of pathogens is important to implement strict infection prevention and control measures in the hospital to prevent the transmission of the resistant pathogens. KEY WORDS Multidrug-Resistant Bacteria, Bla NDM-1 Gene, Bla OXA-48 Gene, Carbapenem Resistance, Carbapenem Resistant Organisms.

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In VitroActivity of LYS228, a Novel Monobactam Antibiotic, against Multidrug-ResistantEnterobacteriaceae

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00552-18 ◽

2018 ◽

Vol 62 (10) ◽

Cited By ~ 16

Author(s):

Johanne Blais ◽

Sara Lopez ◽

Cindy Li ◽

Alexey Ruzin ◽

Srijan Ranjitkar ◽

...

Keyword(s):

Escherichia Coli ◽

Klebsiella Pneumoniae ◽

Carbapenem Resistance ◽

Multidrug Resistant ◽

Minimal Bactericidal Concentration ◽

Content Type ◽

Carbapenem Resistant ◽

Time Kill ◽

Reference Strains ◽

M 14

ABSTRACTLYS228 is a novel monobactam with potent activity againstEnterobacteriaceae. LYS228 is stable to metallo-β-lactamases (MBLs) and serine carbapenemases, includingKlebsiella pneumoniaecarbapenemases (KPCs), resulting in potency against the majority of extended-spectrum β-lactamase (ESBL)-producing and carbapenem-resistantEnterobacteriaceaestrains tested. Overall, LYS228 demonstrated potent activity against 271Enterobacteriaceaestrains, including multidrug-resistant isolates. Based on MIC90values, LYS228 (MIC90, 1 μg/ml) was ≥32-fold more active against those strains than were aztreonam, ceftazidime, ceftazidime-avibactam, cefepime, and meropenem. The tigecycline MIC90was 4 μg/ml against the strains tested. AgainstEnterobacteriaceaeisolates expressing ESBLs (n= 37) or displaying carbapenem resistance (n= 77), LYS228 had MIC90values of 1 and 4 μg/ml, respectively. LYS228 exhibited potent bactericidal activity, as indicated by low minimal bactericidal concentration (MBC) to MIC ratios (MBC/MIC ratios of ≤4) against 97.4% of theEnterobacteriaceaestrains tested (264/271 strains). In time-kill studies, LYS228 consistently achieved reductions in CFU per milliliter of 3 log10units (≥99.9% killing) at concentrations ≥4× MIC forEscherichia coliandK. pneumoniaereference strains, as well as isolates encoding TEM-1, SHV-1, CTX-M-14, CTX-M-15, KPC-2, KPC-3, and NDM-1 β-lactamases.

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Carbapenem resistant Escherichia coli and Pseudomonas aeruginosa in captive blackbucks (Antilope cervicapra) and leopards (Panthera pardus) from India

Veterinarski arhiv ◽

10.24099/vet.arhiv.0829 ◽

2021 ◽

Vol 91 (1) ◽

pp. 73-80

Author(s):

Obli R. Vinodh Kumar ◽

◽

Bhoj R. Singh ◽

Mathesh Karikalan ◽

Shikha Tamta ◽

...

Keyword(s):

Efflux Pump ◽

Carbapenem Resistance ◽

Multidrug Resistant ◽

Beta Lactamases ◽

E Coli ◽

Carbapenem Resistant ◽

Faecal Samples ◽

Carbapenemase Gene ◽

Extended Spectrum Beta Lactamases ◽

Antilope Cervicapra

The study aimed to investigate the occurrence of carbapenem resistant E. coli and P. aeruginosa in apparently healthy, captive blackbucks and leopards of India. Faecal samples of blackbucks (n = 7) and leopards (n = 7) were processed to isolate carbapenem resistant E. coli (CRE) and P. aeruginosa (CRP). Forty (leopards n = 26; blackbuck n = 14) E. coli and two P. aeruginosa (blackbuck n = 2) samples were isolated from the faecal samples (n = 14). Eleven carbapenem resistant isolates were recovered, of which 10 were CRE and one was CRP. The minimum inhibitory concentration (MIC) was determined for meropenem for carbapenem resistant isolates and was between 8 and 64 μg/mL. All the CRE and CRP were phenotypically multidrug resistant, and six CRE were extended-spectrum beta-lactamases (ESBL) producers. On genotypic screening, seven CRE and one CRP were positive for the blaNDM carbapenemase gene. Efflux pump-mediated carbapenem resistance was noticed in four CRE isolates (36.4%, 4/11). Of the six ESBL producing CRE, four isolates carried blaCTX-M-1 genes. The CRE isolates also harbored blaTEM-1, blaAmpC, qnrA, qnrB, qnrS, tetA, tetB and sul1 resistance genes. On Shiga toxin virulence screening, Stx1, Stx2 genes were detected in two and one isolates, respectively. Plasmid typing of CRE revealed that the blaNDM genes were carried on an Incl1 plasmid. The plasmid multilocus sequence typing (pMLST) of the isolates showed the Sequence Type (ST) 297. The occurrence of carbapenem resistance bacteria in captive wildlife should be a major public health priority.

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Anatomic, Geographic, and Taxon-Specific Relative Risks of Carbapenem Resistance in the Health Care System of the U.S. Department of Defense

Journal of Clinical Microbiology ◽

10.1128/jcm.00359-16 ◽

2016 ◽

Vol 54 (6) ◽

pp. 1546-1551 ◽

Cited By ~ 5

Author(s):

Emil Lesho ◽

Uzo Chukwuma ◽

Michael Sparks ◽

Charlotte Neumann ◽

Douglas Richesson ◽

...

Keyword(s):

Temporal Trends ◽

Carbapenem Resistance ◽

Bloodstream Infections ◽

Content Type ◽

Geographically Dispersed ◽

Relative Risks ◽

Carbapenem Resistant ◽

Acinetobacter Spp ◽

Resistant Strains ◽

Care System

Carbapenem-resistantPseudomonasaeruginosa,Acinetobacterspp., andEnterobacteriaceaepose urgent public health threats. The differential burden, relative risks, associations with antimicrobial consumption, and temporal trends of those taxa in large, geographically diverse U.S. health systems remain under reported. Electronic records of all patients in a geographically dispersed 280-hospital managed-care system from 2005 to 2014 were reviewed. Carbapenem-resistant strains were identified based on Clinical and Laboratory Standards Institute guidelines and breakpoints. A total of 360,000 potentially carbapenem-resistant strains were identified from 14.7 million cultures (80% infecting and 20% surveillance). Isolation of bacteria overseas or isolation from the bloodstream was associated with a higher relative risks of carbapenem resistance (CR;P< 0.0001).Enterobacteriaceaewere isolated 11 times more frequently thanP. aeruginosaandAcinetobacterspp. However, compared toEnterobacteriaceae, the CR levels were 73-fold and 210-fold higher in P. aeruginosa andAcinetobacterspp., respectively. Significant differences in the relative risk of CR between taxa, anatomic, and geographic locations persisted after adjustment for other variables, the biggest differences occurring between taxa. Overall, CR rates increased forEnterobacteriaceae(P= 0.03) and decreased for Acinetobacter spp. and P. aeruginosa (P< 0.0001). These data provide a useful baseline for resistance trending and have implications for surveillance. Infections acquired overseas and bloodstream infections are particularly important areas for continued monitoring.

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Acinetobacter radioresistens as a Silent Source of Carbapenem Resistance for Acinetobacter spp.

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01304-07 ◽

2008 ◽

Vol 52 (4) ◽

pp. 1252-1256 ◽

Cited By ~ 121

Author(s):

Laurent Poirel ◽

Samy Figueiredo ◽

Vincent Cattoir ◽

Alessandra Carattoli ◽

Patrice Nordmann

Keyword(s):

Acinetobacter Baumannii ◽

Bacterial Species ◽

Carbapenem Resistance ◽

Acinetobacter Radioresistens ◽

Carbapenemase Gene ◽

Acinetobacter Spp ◽

Plasmid Backbone

ABSTRACT Carbapenem resistance results mostly from the expression of acquired carbapenem-hydrolyzing oxacillinases in Acinetobacter baumannii. The bla OXA-23 oxacillinase gene is increasingly reported worldwide and may represent an emerging threat. Our goal was to identify the progenitor of that carbapenemase gene. A collection of 50 Acinetobacter sp. strains corresponding to several Acinetobacter species was screened for bla OXA-23-like genes by PCR and hybridization techniques. Five Acinetobacter radioresistens isolates that were susceptible to carbapenems harbored chromosomally encoded bla OXA-23-like genes. A similar plasmid backbone was identified in several bla OXA-23-positive A. baumannii and A. radioresistens isolates, further strengthening the vectors of exchanges for these bla OXA-23-like genes. Therefore, A. radioresistens, a commensal bacterial species which is identified on the skin of hospitalized and healthy patients (a property shared with A. baumannii), was identified as the source of the bla OXA-23 gene.

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mCIM test as a reliable assay for the detection of CRE in the Gulf region

Journal of Medical Microbiology ◽

10.1099/jmm.0.001381 ◽

2021 ◽

Vol 70 (7) ◽

Author(s):

Safiya Al Musawi ◽

Jawad Ur Rahman ◽

Salma Ali Aljaroodi ◽

Lateefah AlShammari ◽

Ahmed Itbaileh ◽

...

Keyword(s):

Saudi Arabia ◽

Multidrug Resistant ◽

Gulf Region ◽

Content Type ◽

Link Type ◽

Carbapenem Resistant ◽

Resource Limited ◽

Assay Performance ◽

Carbapenemase Gene ◽

Phenotypic Methods

Introduction. Carbapenem resistant Enterobacterales (CRE) are one of the leading causes of systemic and nosocomial infections and are multidrug-resistant organisms producing different carbapenemases. There are many genotypic and phenotypic methods for detecting the carbapenemases; however, there is a limitation for each. Modified carbapenem inactivation method (mCIM) assay is a recent phenotypic method which has been published by the Clinical and Laboratory Standards Institute. Hypothesis / Gap Statement. mCIM assay could provide a reliable method for the detection of carbapenemases in CRE. Aim. Evaluation of the mCIM assay performance for the detection of carbapenemases in Enterobacterales and the identification of the common carbapenemase genes at Eastern Province of Saudi Arabia and Kingdom of Bahrain. Methodology. A collection of 197 non-duplicate carbapenem resistant Enterobacterales clinical isolates, were evaluated with the mCIM test comparing its performance to multiplex PCR. The minimum inhibitory concentration susceptibility testing was done by the Etest method for imipenem, meropenem, and ertapenem. Results. The sensitivity of the mCIM assay was 94 % (95 % CI, (89.3–97.1)). In Saudi Arabia and Bahrain, OXA-48 was the most prevalent carbapenemase gene followed by NDM. Coexistence of multiple carbapenemase genes is reported in eleven cases. Conclusion. These findings indicate that the mCIM test is a reliable and simple assay for detecting the activity of carbapenemase in Enterobacterales , especially in resource-limited laboratories.

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Epidemiology and Clinical Characteristics ofAcinetobacterPeritoneal Dialysis-Related Peritonitis in Hong Kong—with a Perspective on Multi-Drug and Carbapenem Resistance

Peritoneal Dialysis International ◽

10.3747/pdi.2016.00123 ◽

2017 ◽

Vol 37 (2) ◽

pp. 177-182 ◽

Cited By ~ 4

Author(s):

Philip Hei Li ◽

Vincent C.C. Cheng ◽

Terence Yip ◽

Desmond Y.H. Yap ◽

Sing-Leung Lui ◽

...

Keyword(s):

Treatment Failure ◽

Clinical Characteristics ◽

Antibiotic Sensitivity ◽

Carbapenem Resistance ◽

Multidrug Resistant ◽

Progressive Increase ◽

The Past ◽

Carbapenem Resistant ◽

Acinetobacter Spp ◽

The Impact

BackgroundAcinetobacter spp. is an important cause of peritoneal dialysis (PD)-related peritonitis, but studies on Acinetobacter peritonitis have been scarce. In view of the rising concern of carbapenem-resistant Acinetobacter (CRA) and multidrug-resistant Acinetobacter (MDRA) infections, we conducted this study on the incidence of Acinetobacter peritonitis and the impact of CRA and MDRA on its outcome.MethodsWe retrospectively evaluated the clinical characteristics, prevalence, antibiotic sensitivity patterns, outcomes, and factors associated with treatment failure over the past 16 years in our patients with Acinetobacter PD-related peritonitis.ResultsOut of 2,389 episodes of peritonitis, there were 66 episodes (3%) of Acinetobacter peritonitis occurring in 59 patients. Twelve episodes were caused by MDRA (18%), of which 5 were CRA (8%). There was a progressive increase in the incidence of MDRA and CRA infections over the study period. Most isolates were sensitive to sulbactam combinations (ampicillin-sulbactam [95.4%] and cefoperazone-sulbactam [93.9%]), aminoglycosides (amikacin [92.4%], tobramycin [90.9%], and gentamicin [89.4%]), and carbapenems (imipenem [92.2%]). There was 1 case of relapse. Fifteen episodes resulted in catheter removal (23%), and 7 patients died (11%). Hypoalbuminemia (odds ratio [OR] = 0.85, p = 0.006) and carbapenem resistance (OR = 18.2, p = 0.049) were significantly associated with higher rates of treatment failure.ConclusionBoth carbapenem resistance and hypoalbuminemia were significantly associated with treatment failure. Up to 80% of peritonitis episodes by CRA resulted in catheter loss or mortality. Sulbactam combinations and/or aminoglycosides remained effective for the majority of Acinetobacter isolates. There seemed to be an increasing relative incidence of MDRA and CRA infections over the past 16 years.

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National trends in hospital, long-term care and outpatient Acinetobacter baumannii resistance rates

Journal of Medical Microbiology ◽

10.1099/jmm.0.001473 ◽

2021 ◽

Vol 70 (12) ◽

Author(s):

Haley J. Appaneal ◽

Emily O’Neill ◽

Vrishali V. Lopes ◽

Kerry L. LaPlante ◽

Aisling R. Caffrey

Keyword(s):

Type Species ◽

Long Term Care ◽

Carbapenem Resistance ◽

Multidrug Resistant ◽

Term Care ◽

Content Type ◽

Link Type ◽

Carbapenem Resistant ◽

Resistance Rates

Introduction. Acinetobacter baumannii is a top-priority pathogen of the World Health Organization (WHO) and the Centers for Disease Control (CDC) due to antibiotic resistance. Gap Statement. Trends in A. baumannii resistance rates that include community isolates are unknown. Aim. Identify trends in A. baumannii resistance rates across the Veterans Affairs (VA) Healthcare System, including isolates from patients treated in hospitals, long-term care facilities and outpatient clinics nationally. Methodology. We included A. baumannii clinical cultures collected from VA patients from 2010 to 2018. Cultures were categorized by location: VA medical centers (VAMCs), long-term care (LTC) units [community living centers (CLCs)], or outpatient. We assessed carbapenem resistance, multidrug resistance (MDR) and extensive drug resistance (XDR). Time trends were assessed with Joinpoint regression. Results. We identified 19 376 A . baumannii cultures (53% VAMCs, 4% CLCs, 43% outpatient). Respiratory cultures were the most common source of carbapenem-resistant (43 %), multidrug-resistant (49 %) and extensively drug-resistant (21 %) isolates. Over the study period, the number of A. baumannii cultures decreased significantly in VAMCs (11.9% per year). In 2018, carbapenem resistance was seen in 28% of VAMC isolates and 36% of CLC isolates, but only 6% of outpatient isolates, while MDR was found in 31% of VAMC isolates and 36% of CLC isolates, but only 8 % of outpatient isolates. Carbapenem-resistant, multidrug-resistant and extensively drug-resistant A. baumannii isolates decreased significantly in VAMCs and outpatient clinics over time (VAMCs: by 4.9, 7.2 and 6.9%; outpatient: by 11.3, 10.5 and 10.2% per year). Resistant phenotypes remained stable in CLCs. Conclusion. In the VA nationally, the prevalence of A. baumannii is decreasing, as is resistance. Carbapenem-resistant and multidrug-resistant A. baumannii remain common in VAMCs and CLCs. The focus of infection control and antimicrobial stewardship efforts to prevent transmission of resistant A. baumannii should be in hospital and LTC settings.

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CRISPR-Cas9-Mediated Carbapenemase Gene and Plasmid Curing in Carbapenem-Resistant Enterobacteriaceae

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00843-20 ◽

2020 ◽

Vol 64 (9) ◽

Cited By ~ 1

Author(s):

Mingju Hao ◽

Yuzhang He ◽

Haifang Zhang ◽

Xiao-Ping Liao ◽

Ya-Hong Liu ◽

...

Keyword(s):

Clinical Intervention ◽

Carbapenem Resistance ◽

Plasmid Curing ◽

Content Type ◽

Carbapenem Resistant ◽

Fold Reduction ◽

Carbapenemase Gene ◽

Enterobacter Hormaechei ◽

Generation Sequencing ◽

Carbapenem Resistant Enterobacteriaceae

ABSTRACT Combating plasmid-mediated carbapenem resistance is essential to control and prevent the dissemination of carbapenem-resistant Enterobacteriaceae (CRE). Here, we conducted a proof-of-concept study to demonstrate that CRISPR-Cas9-mediated resistance gene and plasmid curing can effectively resensitize CRE to carbapenems. A novel CRISPR-Cas9-mediated plasmid-curing system (pCasCure) was developed and electrotransferred into various clinical CRE isolates. The results showed that pCasCure can effectively cure blaKPC, blaNDM, and blaOXA-48 in various Enterobacteriaceae species of Klebsiella pneumoniae, Escherichia coli, Enterobacter hormaechei, Enterobacter xiangfangensis, and Serratia marcescens clinical isolates, with a >94% curing efficiency. In addition, we also demonstrated that pCasCure can efficiently eliminate several epidemic carbapenem-resistant plasmids, including the blaKPC-harboring IncFIIK-pKpQIL and IncN pKp58_N plasmids, the blaOXA-48-harboring pOXA-48-like plasmid, and the blaNDM-harboring IncX3 plasmid, by targeting their replication and partitioning (parA in pKpQIL) genes. However, curing the blaOXA-48 gene failed to eliminate its corresponding pOXA-48-like plasmid in clinical K. pneumoniae isolate 49210, while further next-generation sequencing revealed that it was due to IS1R-mediated recombination outside the CRISPR-Cas9 cleavage site resulting in blaOXA-48 truncation and, therefore, escaped plasmid curing. Nevertheless, the curing of carbapenemase genes or plasmids, including the truncation of blaOXA-48 in 49210, successfully restore their susceptibility to carbapenems, with a >8-fold reduction of MIC values in all tested isolates. Taken together, our study confirmed the concept of using CRISPR-Cas9-mediated carbapenemase gene and plasmid curing to resensitize CRE to carbapenems. Further work is needed to integrate pCasCure in an optimal delivery system to make it applicable for clinical intervention.

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