Science and Technology Production
Outbreak of NDM-5-producing Klebsiella variicola in intensive care units: an overlooked pathogen in Argentina?

Article

Authorship
GONZALEZ ESPINOSA, FRANCISCO EDUARDO ; Maurizi, Diego Marcelo ; Pedersen, Dina ; Oriani, Alejandra Soledad ; Martinez, Celeste ; Martínez Lozano, Jerson Andrés ; Gutkind, Gabriel ; Radice, Marcela ; Cejas, Daniela
Date
2025
Publishing House and Editing Place
American Society for Microbiology ASM
Magazine
Microbiology Spectrum, vol. 13 American Society for Microbiology ASM
Summary Information provided by the agent in SIGEVA
Here, we characterized the first Klebsiella variicola isolates responsible for an outbreak in the intensive care units (ICUs) in a hospital in Argentina. Five isolates recovered from inpatients and sinks at the ICUs of one hospital in Bahia Blanca City were included. Identification and antimicrobial susceptibility tests were performed using an automated system (Phoenix). Besides, they were identified using two mass spectrometry systems (Bruker Daltonics and BioMérieux) and a multiplex-PC... Here, we characterized the first Klebsiella variicola isolates responsible for an outbreak in the intensive care units (ICUs) in a hospital in Argentina. Five isolates recovered from inpatients and sinks at the ICUs of one hospital in Bahia Blanca City were included. Identification and antimicrobial susceptibility tests were performed using an automated system (Phoenix). Besides, they were identified using two mass spectrometry systems (Bruker Daltonics and BioMérieux) and a multiplex-PCR for Klebsiella pneumoniae complex identification. Whole-genome sequencing (WGS) was conducted to confirm bacterial identification and to analyze their resistome and mobilome. Additionally, clonal and phylogenetic relationships were investigated among local and worldwide isolates. Based on the Phoenix system, all isolates were identified as K. pneumoniae and resistant to last-line antibiotics, consistent with a difficult-to-treat phenotype (DTR). All of them carried blaNDM-5. The isolates were identified as K. variicola by one of the Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) systems and by multiplex-PCR. WGS confirmed all isolates as K. variicola subsp. variicola belonging to ST3029, an infrequent lineage among the genomes analyzed. They displayed fewer than six SNPs, which corresponded to a unique clone, and the phylogenetic analysis exhibited a close relationship with isolates recovered from an environmental source in Brazil.
Show more Show less
Key Words
NDM-5ArgentinaST3029Klebsiella variicola