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The Resist Acineto from Coris Bioconcept is a novel immunochromatographic test for detection of the major acquired carbapenemases (OXA-23, OXA-40, OXA-58, and NDM) identified in Acinetobacter spp. This rapid and easy-to-perform test showed an excellent specificity and sensitivity, with positive and negatives predictive values of 100% in both cases., Competing Interests: Declaration of Competing Interest PN and LP are inventors of the Rapid Acineto Carba NP test aimed to identify biochemically carbapenemase production in Acinetobacter baumannii., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Objectives: OXA-48-like carbapenemases have spread worldwide since 2001. We analysed patient and microbiological data for UK isolates with these enzymes as confirmed by the national reference laboratory from November 2007 to December 2014., Methods: MICs were determined using BSAC agar dilution. Isolates with reduced susceptibility or resistance to at least one carbapenem and high-level resistance to both piperacillin/tazobactam (MICs ≥64 mg/L) and temocillin (MICs ≥128 mg/L) were screened by PCR for bla OXA-48-like genes. The genomes of about half of the isolates were sequenced, with MLST types, resistance genes and plasmid replicon types inferred. Patient data provided by sending laboratories were reviewed., Results: Isolates ( n  =   741) with OXA-48-like carbapenemases were submitted from 111 UK laboratories, representing 536 patients. Almost all (99%; 736 of 741) were Enterobacteriaceae, predominantly Klebsiella pneumoniae (55%; 408), and most (80%; 595) were from inpatients. WGS of 351 non-duplicate isolates identified bla OXA-48 as the most common variant, found in two-thirds (235 of 351) of isolates, followed by bla OXA-181 (68), bla OXA-232 (32), bla OXA-244 (10), bla OXA-484 (5) and bla OXA-245 (1). Among K. pneumoniae (163 of 351), Escherichia coli (114 of 351) and Enterobacter cloacae (42 of 351), 119 STs were identified. Mapping analyses revealed that 63% (222 of 351) of isolates harboured plasmids that shared >99% identity to one of four known plasmids [pOXA-48a (44%; 154 of 351), pOXA-232 (10%; 34 of 351), pOXA181 (9%; 30 of 351) and pKP3-A (1%; 4 of 351)]; the remaining 37% of isolates harboured bla OXA-48-like in unknown environments., Conclusions: OXA-48-like carbapenemases are an increasing problem in the UK. This study highlights both the role of successful plasmids and the polyclonal nature of their dissemination., (© Crown copyright 2017.)

Objectives: Carbapenemase-producing Enterobacteriaceae (CPE) have been increasingly reported in the UK since 2003. We analysed patient and isolate data for CPE confirmed by the national reference laboratory from laboratories in the West Midlands region from November 2007 to December 2014., Methods: MICs were determined by BSAC agar dilution methodology and isolates exhibiting resistance to one or more carbapenems were screened for carbapenemase genes by PCR. Plasmid analyses were performed after electro-transformation of carbapenemase-encoding plasmids. WGS was performed on both transformants and clinical isolates. Patient data provided by the sending laboratories were reviewed., Results: During the study period, CPE ( n  = 139) were submitted from 13 laboratories in the West Midlands region, originating from 108 patients and including one environmental isolate. CPE submissions increased significantly from 2009 onwards. Isolates were predominantly Klebsiella pneumoniae (89/139) obtained from inpatients. WGS was performed on all clinical isolates and transformants. After deduplication 119 isolates and 96 transformants remained for analysis. Within these, four families of carbapenemase genes were identified: bla NDM (69/119), bla KPC (26/119), bla OXA-48-like (16/119) and bla VIM (7/119); one isolate carried both bla NDM and bla OXA-48-like . Isolates represented diverse STs and plasmid replicon types. Plasmid analyses identified plasmids of different replicon types encoding bla KPC , bla NDM and bla OXA-48-like genes, found across several species and STs., Conclusions: CPE have been reported increasingly in the West Midlands region over a 7 year period. bla NDM , bla KPC and bla OXA-48-like were the dominant carbapenemase genes and were found in a range of diverse genomic/plasmid environments, highlighting their ability to mobilize across different plasmids, often impeding the detection of outbreaks., (© Crown copyright 2017.)

Objectives: Klebsiella pneumoniae carbapenemases (KPCs) have been increasingly reported in the UK since 2003. We analysed patient and isolate data for KPC-positive bacteria confirmed by the national reference laboratory from UK laboratories from August 2003 to August 2014, excluding North-West England, where the epidemiology has previously been studied., Methods: MICs were determined by BSAC agar dilution. Carbapenem-resistant isolates lacking imipenem/EDTA synergy were tested by PCR for blaKPC. MLST and blaKPC sequencing were performed on a subset of isolates. Plasmid analysis was performed by transformation, PCR-based replicon typing and, in some cases, whole-plasmid sequencing. Patient data provided by the sending laboratories were reviewed., Results: Two hundred and ten isolates with KPC enzymes were submitted from 71 UK laboratories outside North-West England, representing 160 patients. All were Enterobacteriaceae, predominantly K. pneumoniae (82%; 173/210), and most (91%; 191/210) were from hospitalized patients. Analysis of 100 isolates identified blaKPC-2 (62%), blaKPC-3 (30%) and blaKPC-4 (8%). Clonal group (CG) 258 was dominant among K. pneumoniae (64%; 54/84), but 21 unrelated STs were also identified. Plasmid analysis identified a diverse range of plasmids representing >11 different replicon types and found in multiple STs and species. Most (34/35) plasmids with IncFIB/FIIK replicons exhibited >99% sequence identity to pKpQIL., Conclusions: KPC enzymes are increasingly detected in Enterobacteriaceae in the UK, albeit without the major outbreaks seen in North-West England. K. pneumoniae CG258 are the dominant hosts, but plasmid spread plays a major role in KPC dissemination between other K. pneumoniae STs and enterobacterial species., (© The Author 2016. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.)

Objectives: To assess the performance of three commercial molecular assays for detecting major families of carbapenemases in pure bacterial isolates., Methods: A panel of 450 isolates with previously defined carbapenem resistance mechanisms was tested using the Check-Direct CPE kit, the eazyplex(®) SuperBug complete A kit and the Xpert(®) Carba-R kit. Isolates included 438 Enterobacteriaceae and 12 Pseudomonas spp. comprising 100 isolates each with KPC, NDM, VIM or OXA-48-like enzymes, two isolates producing both an NDM and an OXA-48-like enzyme, 24 IMP producers and 24 isolates without a known carbapenemase gene. Discordant results (commercial versus in-house) were investigated using in-house PCR and amplicons were sequenced to define the carbapenemase allele present., Results: All three commercial assays detected all isolates with KPC, VIM, NDM and classic OXA-48 carbapenemases (no false-negatives). Isolates producing the OXA-181 variant (n = 18) were not detected by the Xpert(®) Carba-R kit or the eazyplex(®) SuperBug complete A kit, but were subsequently detected with modified versions of these kits. Only the Xpert(®) Carba-R kit could detect IMP carbapenemases, although this was limited to the IMP-1 subgroup. Invalid or false-positive results were either not observed when following the manufacturer's protocols or were eliminated by making simple interpretative adjustments to allow use with bacterial isolates rather than clinical samples., Conclusions: Commercial assays offer a reliable means of detecting bacteria with clinically significant carbapenemases. Coverage of some assays required expansion to maximize the sensitivity for OXA-48-like carbapenemases. Choice will ultimately depend on preferred gene coverage, intended throughput, cost and ability to fit into local workflows., (© Crown copyright 2015.)

We sought to detect and determine the genetic diversity of carbapenemase-producing Enterobacteriaceae (CPE) isolated from clinical specimens in Amman, Jordan. From five hospitals, a total of 2,759 isolates had antimicrobial susceptibilities determined via Vitek II, of which 28 (1%) were carbapenem resistant. Species identifications were determined via matrix-assisted laser desorption ionization time-of-flight mass spectrometry and carbapenemase gene detection via real-time PCR indicated that 23 (82.1%) isolates were Klebsiella pneumoniae (OXA-48-like, n = 7; NDM, n = 14; OXA-48-like and NDM, n = 2), four (14.2%) were Enterobacter cloacae complex (NDM, n = 3 and VIM, n = 1), and one (3.5%) was Escherichia coli (NDM). Sequencing of carbapenemase gene amplicons from a subset of isolates identified blaNDM-1, blaOXA-48, and blaVIM-4 alleles. Strain typing detected seven different K. pneumoniae variable number tandem repeat types, consistent with mostly sporadic occurrences along with limited clonal spread. E. cloacae complex isolates were diverse by pulsed-field gel electrophoresis, with a maximum relatedness of 70%. Plasmid restriction fragment length polymorphism (pRFLP) revealed four distinct profiles associated with NDM-encoding plasmids that were positive for replicons of the FII(K)/FIB or FIB incompatibility (Inc) groups via PCR-based replicon typing. OXA-48-encoding IncL/M plasmids differed by two pRFLP bands. The results show diverse CPE produce OXA-48 and NDM-1 enzymes in Jordan and that the carbapenemase genes are distributed on diverse plasmids in Jordanian hospitals, with some limited evidence for related clusters occurring, emphasizing the need for strict infection control measures. [ABSTRACT FROM AUTHOR]

Background: Carbapenemase-producing Enterobacteriaceae (CPE), including KPC-producing Klebsiella pneumoniae (KPC-Kpn), are an increasing threat to patient safety.Objectives: To use WGS to investigate the extent and complexity of carbapenemase gene dissemination in a controlled KPC outbreak.Materials and Methods: Enterobacteriaceae with reduced ertapenem susceptibility recovered from rectal screening swabs/clinical samples, during a 3 month KPC outbreak (2013-14), were investigated for carbapenemase production, antimicrobial susceptibility, variable-number-tandem-repeat profile and WGS [short-read (Illumina), long-read (MinION)]. Short-read sequences were used for MLST and plasmid/Tn4401 fingerprinting, and long-read sequence assemblies for plasmid identification. Phylogenetic analysis used IQTree followed by ClonalFrameML, and outbreak transmission dynamics were inferred using SCOTTI.Results: Twenty patients harboured KPC-positive isolates (6 infected, 14 colonized), and 23 distinct KPC-producing Enterobacteriaceae were identified. Four distinct KPC plasmids were characterized but of 20 KPC-Kpn (from six STs), 17 isolates shared a single pKpQIL-D2 KPC plasmid. All isolates had an identical transposon (Tn4401a), except one KPC-Kpn (ST661) with a single nucleotide variant. A sporadic case of KPC-Kpn (ST491) with Tn4401a-carrying pKpQIL-D2 plasmid was identified 10 months before the outbreak. This plasmid was later seen in two other species and other KPC-Kpn (ST14,ST661) including clonal spread of KPC-Kpn (ST661) from a symptomatic case to nine ward contacts.Conclusions: WGS of outbreak KPC isolates demonstrated blaKPC dissemination via horizontal transposition (Tn4401a), plasmid spread (pKpQIL-D2) and clonal spread (K. pneumoniae ST661). Despite rapid outbreak control, considerable dissemination of blaKPC still occurred among K. pneumoniae and other Enterobacteriaceae, emphasizing its high transmission potential and the need for enhanced control efforts. [ABSTRACT FROM AUTHOR]

The performance and portability of a multiplex real-time PCR assay to detect KPC, NDM, OXA-48-like and VIM carbapenemase gene families from bacterial isolates was assessed using Rotor-Gene Q and ABI 7500 instruments. Gram-negative bacterial isolates ( n = 502) were comprised of 100 isolates each with KPC, NDM, VIM or OXA-48-like carbapenemases (including 17 with OXA-181) and 2 isolates with NDM + OXA-48-like enzymes (including 1 with OXA-181) as well as 100 assay-negative isolates comprised of 24 IMP-producers, 24 carbapenem-resistant isolates with no known carbapenemase gene and 52 extended-spectrum β-lactamase-producing carbapenem-susceptible isolates. A multicentre evaluation was carried out in five laboratories using a subset of 100 isolates comprised of 22 isolates each with KPC, NDM, OXA-48-like or VIM alleles and 12 isolates that were negative for the assay targets. Initial validation of the assay on both the Rotor-Gene Q and ABI 7500 instruments demonstrated 100% sensitivity amongst the 402 isolates that were positive for KPC, NDM, OXA-48-like (including OXA-181) and VIM carbapenemase genes, whilst the 100 assay-negative samples were correctly identified indicating 100% specificity. During the multicentre evaluation the same 100% level of sensitivity and specificity was observed in each of the five centres that participated. Neither invalid nor false-positive results were observed. In conclusion, the assay offers a portable and reliable option for the detection of bacteria carrying clinically significant carbapenemases encoded by KPC, NDM, VIM and OXA-48-like carbapenemase genes using either of the two most common real-time PCR instrument platforms. [ABSTRACT FROM AUTHOR]

The article discusses a research study on an IMI-2 carbapenemase in a Klebsiella variicola strain isolated in Great Britain. The strain was isolated from an intensive therapy unit patient in 2011 from a soft tissue infection of the buttock. It is stated that this is the first report of an IMI carbapenemase outside of the Enterobacter cloacae complex in Britain.