Becerra-Aparicio, FedericoGómez-Zorrilla, SilviaSiverio, AnaDuran Jordà, Xavier, 1974-Horcajada Gallego, Juan PabloRuiz-Garbajosa, Patricia2025-05-122025-05-122025Becerra-Aparicio F, Gómez-Zorrilla S, Hernández-García M, Xanthopoulou K, Gijón D, Siverio A, et al. Whole genome sequencing analysis of Klebsiella pneumoniae isolates from health care-associated bacteremia of urinary origin in Spain: Findings from the multicenter ITUBRAS-2 cohort study. Open Forum Infect Dis. 2025 Mar 15;12(4):ofaf164. DOI: 10.1093/ofid/ofaf1642328-8957http://hdl.handle.net/10230/70345Background: The objective of this study was to assess the microbiological and clinical features of Klebsiella pneumoniae health care-associated bacteremia of urinary origin (HCA-BUO) in Spain, with a focus on third-generation cephalosporin-(3GCR-Kp) and carbapenem-resistant K pneumoniae (CR-Kp) isolates. Methods: A total of 96 (21.4%, 96/449) K pneumoniae blood isolates were prospectively collected from patients with HCA-BUO (n = 443) from 12 tertiary care hospitals in Spain (2017-2019). Antimicrobial susceptibility was determined (standard broth microdilution), and extended-spectrum β-lactamase, AmpC, and carbapenemase production was screened. A subset of 55 K pneumoniae isolates was analyzed by whole genome sequencing (Illumina) to determine population structure, resistome, and virulome. Additionally, 13 of these isolates were subjected to long-read sequencing (Nanopore) for plasmid characterization. Patients' baseline and clinical characteristics were reviewed. Results: 3GCR-Kp prevalence was 43.8% (42/96), mostly associated with extended-spectrum β-lactamase production (34/96, 35.4%; mainly CTX-M-15, 32/34, 94.1%) and the dissemination of sequence type (ST)-307 (15/34, 44.1%) and other globally spread multidrug-resistant high-risk clones. CR-Kp prevalence was 9.4% (9/96); all isolates belonged to different STs and were mostly associated with carbapenemase production (6/9, 66.7%; mainly OXA-48-like, n = 3). Additionally, 3GCR-Kp and CR-Kp isolates showed higher content of other antibiotic resistance genes. Altogether, these episodes were associated with prior antibiotic use and receipt of inadequate empirical treatment. Conclusions: There is a high prevalence of 3GCR and CR-Kp causing HCA-BUO in Spain, mainly driven by the dissemination of ST307/CTX-M-15 and other globally spread multidrug-resistant high-risk clones, challenging the selection of empirical and targeted treatments for these infections.application/pdfeng© The Author(s) 2025. Published by Oxford University Press on behalf of Infectious Diseases Society of America. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs licence (https://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial reproduction and distribution of the work, in any medium, provided the original work is not altered or transformed in any way, and that the work is properly cited. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.info:eu-repo/semantics/articlehttp://dx.doi.org/10.1093/ofid/ofaf164Klebsiella pneumoniaeST307 cloneCarbapenemase-producing EnterobacteralesExtended-spectrum β-lactamasesHealth care–associated infectionsinfo:eu-repo/semantics/openAccess