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To analyze the drug-resistant phenotype and genetic characteristics of Carbapenem resistant Klebsiella pneumoniae (CRKP) in this region, and to study its different expression profiles in RNA level under the pressure of low levels of antibiotics. Trace dilution method and PCR method were used to detect the antibiotic resistance phenotype and antibiotic resistance gene carrying of CRKP strain, simulate the antibiotic stress process, and RNAseq was used to analyze the transcriptomic changes of CRKP strain. 37 CRKP strains, 27 Carbapenem sensitive Klebsiella pneumoniae (CSKP) CSKP strains and 42 sensitive strains were detected. The antibiotic resistance rate of CRKP strain was significantly higher than that of other drug-resistant strains, and there were many kinds of antibiotic resistance genes. Transcriptomic analysis showed that CRKP strain showed compensatory rise under meropenem stress at low concentration, and the expression of genes related to biofilm formation, pressure induction, pressure tolerance and transcriptional regulation was significantly changed. It was speculated that mrkAB , fimDH , phoHP and pspABCD clusters significantly altered their expression under the antibiotics stress response in CRKP strain. The detection rate of CRKP strain is high in this area. Under low levels of antibiotic stress, CRKP strain can not only survive by synthesizing antibiotic modified enzyme, but also respond by transcriptional regulation and biofilm changes, resulting in stress compensation. The discovery of this phenomenon explains the failure of treatment due to improper use of higher-order antibiotics from the perspective of genetic interaction. [Display omitted] [ABSTRACT FROM AUTHOR]

Recent emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) coharboring bla KPC-2 and virulence hybrid plasmid, designated pCRHV-C2244, from a clinical ST11-K64 CRKP strain. pCRHV-C2244 was non-self-transmissible due to incomplete conjugative elements but mobilizable together with a conjugative helper. Enhanced virulence and stable maintenance without significant fitness loss in its original host were confirmed bla KPC-2 and virulence hybrid plasmid, designated pCRHV-C2244, from a clinical ST11-K64 CRKP strain. pCRHV-C2244 was non-self-transmissible due to incomplete conjugative elements but mobilizable together with a conjugative helper. Enhanced virulence and stable maintenance without significant fitness loss in its original host were confirmed in vitro and in vivo ., (Copyright © 2021 American Society for Microbiology.)

Background: This study was designed to characterize the dissemination mechanism and genetic context of Klebsiella pneumoniae carbapenemase (KPC) genes in carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates., Methods: A retrospective analysis was performed on CRKP strains isolated from a teaching hospital of Wenzhou Medical University during 2015-2017. Polymerase chain reaction (PCR)-based amplification and whole-genome sequencing (WGS) were used to analyze the genetic context of the bla KPC-2 gene. Conjugation experiments were performed to evaluate the transferability of bla KPC-2 -bearing plasmids. Multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) were performed to investigate the clonal relatedness of bla KPC-2 -producing strains., Results: The bla KPC-2 gene was identified from 13.61% (40/294) of clinical K. pneumoniae isolates. Three different sequence types (ST11, ST15 and ST656) and 5 PFGE subtypes (A to E) were classified among them. ST11 was the dominant sequence type (92.50%, 37/40). Plasmid-oriented antibiotic resistance genes, such as extended spectrum-β-lactamases (ESBLs) and other antimicrobial resistance genes, were also found in KPC-positive K. pneumoniae (KPC- Kp ) isolates. Mapping PCR and genomic sequencing revealed that the bla KPC-2 -bearing sequence regions, which are related to different mobile elements, including Tn1721- and IS26-based transposons, were mainly located in but not restricted to IncFII-like plasmids and were structurally divergent., Conclusion: The bla KPC-2 genes related to divergent mobile genetic elements encoded on transferable plasmids may transfer widely, facilitating the spread of carbapenem resistance among bacteria with different genetic backgrounds. The dissemination of bla KPC -bearing plasmids that collectively carry additional multidrug resistance genes has caused widespread public concern, further limiting the antibiotics available to treat infections caused by KPC-producing pathogens., Competing Interests: The authors report no conflicts of interest in this work., (© 2021 Liu et al.)

Background and Objective: The emergence of carbapenem-resistant K. pneumoniae (CRKP) continues to escalate and is alarming because of the emergence of pan drug-resistant strains. The objective of this study was to investigate the existence of 12 carbapenemase genes among CRKP clinical isolates., Methods: Ninety-six Klebsiella spp. clinical isolates were collected. The isolates were identified phenotypically and genotypically. These isolates were screened for susceptibility to 24 different antibiotics. The modified Hodge test (MHT) and the Carba Nordmann/Poirel (NP) test were used to phenotypically screen carbapenem-resistant strains for carbapenemase production. Phenotypic characterization of carbapenemases was performed using the combined disk synergy test (CDST). Additionally, the presence of 12 carbapenemase genes in CRKP isolates was investigated. The DNA sequence of bla NDM genes was determined. The BOX-PCR technique was used to determine the clonal relationship between CRKP isolates.bla GES genes was determined. The BOX-PCR technique was used to determine the clonal relationship between CRKP isolates., Results: All carbapenem-resistant isolates were related to K. pneumoniae . Susceptibility testing showed that 19.79% (19/96) of the collected isolates were carbapenem-resistant. Of the CRKP isolates, 68.42% (13/19) tested positive for the MHT and Carba NP test. CDST showed that 42.11% (8/19), 63.16% (12/19), 47.37% (9/19), and 73.68% (14/19) of the CRKP isolates tested positive for the inhibitory effect of clavulanic acid, sulbactam, phenylboronic acid, and tazobactam, respectively, while 84.21% (16/19) and 68.42% (13/16) tested positive for the inhibitory effect of EDTA and mercaptopropionic acid, respectively. It was found that 10.53% (2/19) of the isolates tested positive for the inhibitory effect of sodium chloride. Molecular investigation of carbapenemases showed that 26.32% (5/19), 73.68% (14/19), 21.05% (4/19), 10.53% (2/19), and 5.26% (1/19) of the isolates tested positive for bla NDM , bla OXA-48 , bla OXA-181 , bla OXA-51 , and bla OXA-23 ) were detected. BOX-PCR revealed high clonal relatedness between CRKP isolates.bla OXA-40 and bla OXA-58 . Two allelic variants of bla NDM ( bla NDM-1 and bla NDM-25 ) were detected. BOX-PCR revealed high clonal relatedness between CRKP isolates., Conclusion: MHT was more sensitive than Carba NP test for evaluating carbapenemase production and class D carbapenemase genes were the most prevalent of the 12 carbapenemase genes that were evaluated., Competing Interests: The authors declare no conflict of interest in this work., (© 2020 El-Badawy et al.)

Providers Facilitate Transmission of Resistant Organisms; The Time Is Now — Stop CRKP [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the prevalence of carbapenem-resistant Klebsiella pneumoniae (CRKP) and the most common types of carbapenemases, metallo-beta-lactamases (MBLs), and extended-spectrum beta-lactamases (ESBLs) among CRKP isolates in a tertiary hospital in Isfahan, Iran. Eighty non-repetitive clinical isolates of K. pneumoniae were obtained from different clinical specimens. Antibiotic resistance pattern of isolates was determined by disk diffusion method and production of carbapenemases and MBLs was confirmed using modified Hodge test and E-test, respectively. Molecular detection of the antibiotic resistance genes was performed using PCR. Fifty-one (63.8%) isolates have decreased susceptibility to carbapenems, of which 46 (90.2%) isolates were as carbapenemase producer and four (7.8%) isolates were positive for MBLs, phenotypically. The results of PCR showed that the prevalence of bla OXA-48 , bla NDM , bla SHV , bla CTX-M , and bla TEM genes among CRKP isolates were 90.2%, 15.7%, 98%, 96.1%, and 90.2%, respectively. No isolates carrying the bla KPC , bla GES , bla IMI , bla VIM , and bla IMP genes were detected. This study showed that the production of OXA-48 is one of the main mechanisms of resistance to carbapenems in CRKP isolates in Isfahan. In addition, the dissemination of NDM-producing CRKP isolates is a potential risk for the health care system of this area in the near future.

In the last decade, carbapenem-resistant Klebsiella pneumoniae (CR-Kp) has become endemic in several countries, including Italy. In the present study, we assessed the differences in epidemiology, management, and mortality of CR-Kp bloodstream infection (BSI) in the three main adult acute-care hospitals of the metropolitan area of Genoa, Italy. From January 2013 to December 2014, all patients with CR-Kp BSI were identified through the computerized microbiology laboratory databases of the three hospitals. The primary endpoints of the study were incidence and characteristics of CR-Kp BSI in hospitals within the same endemic metropolitan area. Secondary endpoints were characteristics of CR-Kp BSI in hospitals with and without internal infectious diseases consultants (IDCs) and 15-day mortality. During the study period, the incidence of healthcare-associated CR-Kp BSI in the entire study population was 1.35 episodes per 10,000 patient-days, with substantial differences between the three hospitals. Patients admitted to the two hospital with internal IDCs were more likely to receive post-susceptibility test combined therapy including carbapenems (77% vs. 26%, p<0.001), adequate post-susceptibility test therapies (86% vs. 52%, p<0.001), and post-susceptibility therapies prescribed by an infectious diseases specialist (84% vs. 14%, p<0.001). Overall, the crude 15-days mortality was 26%. In the final multivariable model, only septic shock at BSI presentation was unfavorably and independently associated with 15-days mortality (odds ratio [OR] 6.7, 95% confidence intervals [CI] 2.6-17.6, p<0.001), while a protective effect was observed for post-susceptibility test combined therapies including a carbapenem (OR 0.11, 95% CI 0.03-0.43, p=0.002). Mortality of CR-Kp remains high. Differences in the incidence of CR-Kp BSI were detected between acute-care centers within the same endemic metropolitan area. Efforts should be made to improve the collaboration and coordination between centers, to prevent further diffusion of CR-Kp., (Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.)