Karlsson, MariaLutgring, Joseph D.Ansari, UzmaLawsin, AdrianWilson, Lucyet al2022-06-022022-06-022022-04-18Molecular Characterization of Carbapenem-Resistant Enterobacterales Collected in the United States Maria Karlsson, Joseph D. Lutgring, Uzma Ansari, Adrian Lawsin, Valerie Albrecht, Gillian McAllister, Jonathan Daniels, David Lonsway, Susannah McKay, Zintars Beldavs, Chris Bower, Ghinwa Dumyati, Annastasia Gross, Jesse Jacob, Sarah Janelle, Marion A. Kainer, Ruth Lynfield, Erin C. Phipps, Kyle Schutz, Lucy Wilson, Medora L. Witwer, Sandra N. Bulens, Maroya Spalding Walters, Nadezhda Duffy, Alexander J. Kallen, Christopher A. Elkins, and J. Kamile Rasheed Microbial Drug Resistance 2022 28:4, 389-397http://doi.org/10.1089/mdr.2021.0106http://hdl.handle.net/11603/24810Authors: Maria Karlsson, Joseph D. Lutgring, Uzma Ansari, Adrian Lawsin, Valerie Albrecht, Gillian McAllister, Jonathan Daniels, David Lonsway, Susannah McKay, Zintars Beldavs, Chris Bower, Ghinwa Dumyati, Annastasia Gross, Jesse Jacob, Sarah Janelle, Marion A. Kainer, Ruth Lynfield, Erin C. Phipps, Kyle Schutz, Lucy E. Wilson, Medora L. Witwer, Sandra N. Bulens, Maroya Spalding Walters, Nadezhda Duffy, Alexander J. Kallen, Christopher A. Elkins, and J. Kamile RasheedCarbapenem-resistant Enterobacterales (CRE) are a growing public health concern due to resistance to multiple antibiotics and potential to cause health care-associated infections with high mortality. Carbapenemase-producing CRE are of particular concern given that carbapenemase-encoding genes often are located on mobile genetic elements that may spread between different organisms and species. In this study, we performed phenotypic and genotypic characterization of CRE collected at eight U.S. sites participating in active population- and laboratory-based surveillance of carbapenem-resistant organisms. Among 421 CRE tested, the majority were isolated from urine (n = 349, 83%). Klebsiella pneumoniae was the most common organism (n = 265, 63%), followed by Enterobacter cloacae complex (n = 77, 18%) and Escherichia coli (n = 50, 12%). Of 419 isolates analyzed by whole genome sequencing, 307 (73%) harbored a carbapenemase gene; variants of blaKPC predominated (n = 299, 97%). The occurrence of carbapenemase-producing K. pneumoniae, E. cloacae complex, and E. coli varied by region; the predominant sequence type within each genus was ST258, ST171, and ST131, respectively. None of the carbapenemase-producing CRE isolates displayed resistance to all antimicrobials tested; susceptibility to amikacin and tigecycline was generally retained.9 pagesen-USThis work was written as part of one of the author's official duties as an Employee of the United States Government and is therefore a work of the United States Government. In accordance with 17 U.S.C. 105, no copyright protection is available for such works under U.S. Law.Public Domain Mark 1.0http://creativecommons.org/publicdomain/mark/1.0/Text