Anti-Vimentin monoclonal antibody, clone WIM4B5

Objectives: To assess the in vitro antibacterial activity of ceftazidime/avibactam against a recent Italian collection of carbapenem-resistant Enterobacterales (CRE) isolated from urine specimens. Methods: Consecutive Gram-negative isolates from urine specimens, collected from inpatients in five Italian hospitals during the period October 2016 to February 2017, were screened for CRE phenotype using chromogenic selective medium and identified using MALDI-TOF MS. Antimicrobial susceptibility testing was performed by reference broth microdilution (BMD) and, for ceftazidime/avibactam, also by Etest (R) CZA. Results were interpreted according to the EUCAST breakpoints. ALL confirmed CRE were subjected to real-time PCR targeting bla(KPC-t)(ype), bla(VIM-type), bla(NDM-type) and bla(OXA)(-48-type) carbapenemase genes. Non-MBL-producing isolates resistant to ceftazidime/avibactam were subjected to WGS and their resistome and clonality were analysed. Results: Overall, 318 non-replicate presumptive CRE were collected following screening of 9405 isolates of Enterobacterales (3.4%) on chromogenic selective medium. Molecular analysis revealed that 216 isolates were positive for a carbapenemase gene (of which 92.1%, 2.8%, 1.4% and 1.4% were positive for bla(KPC-)(type), bla(OXA-48-type) and bla(NDM-type), bla(VIM-type), respectively). Against the confirmed carbapenemase-producing Enterobacterales (CPE), ceftazidime/avibactam was the most active compound, followed by colistin (susceptibility rates 91.6% and 69.4%, respectively). Compared with BMD, Etest (R) for ceftazidime/avibactam yielded consistent results (100% category agreement). ALL class B beta-Lactamase producers were resistant to ceftazidime/avibactam, while OXA-48 and KPC producers were susceptible, with the exception of seven KPC-producing isolates (4.2%). The Latter exhibited an MIC of 16 to >32 mg/L, belonged to ST512, produced KPC-3 and showed alterations in the OmpK35 and Ompk36 porins. Conclusions: Ceftazidime/avibactam showed potent in vitro activity against a recent Italian collection of CPE from urine.

The aquatic environment takes on a key role in the dissemination of antimicrobial-resistant Enterobacteriaceae. This study assesses the occurrence of carbapenemase-producing Enterobacteriaceae (CPE) in freshwater samples from rivers, inland canals, and streams throughout Switzerland, and characterizes the isolated strains using phenotypic and NGS-based genotypic methods. CPE producing KPC-2 (n = 2), KPC-3 (n = 1), NDM-5 (n = 3), OXA-48 (n = 3), OXA-181 (n = 6), and VIM-1 (n = 2) were detected in 17/164 of the water samples. Seven Escherichia coli had sequence types (STs) that belonged to extraintestinal pathogenic clonal lineages ST38, ST73, ST167, ST410, and ST648. The majority (16/17) of the carbapenemase genes were located on plasmids, including the widespread IncC (n = 1), IncFIIA (n = 1), and IncFIIB plasmids (n = 4), the epidemic IncL (n =1) and IncX3 (n = 5) plasmids, a rare Col156 plasmid (n = 1), and the mosaic IncFIB, IncR, and IncQ plasmids (n = 3). Plasmids were composed of elements that were identical to those of resistance plasmids retrieved from clinical and veterinary isolates locally and worldwide. Our data show environmental dissemination of high-risk CPE clones in Switzerland. Epidemic and mosaic-like plasmids carrying clinically relevant carbapenemase genes are replicating and evolving pollutants of river ecosystems, representing a threat to public health and environmental integrity. (C) 2020 The Authors. Published by Elsevier Ltd.