Detection of rare β-lactamase blaSCO-1 from a Klebsiella pneumoniae high-risk clone in Peru

Palomino-Kobayashi L.A.; Egoávil-Espejo R.; Salvador-Luján G.; Yáñez P.; Gavilán R.G.; Pons M.J.; Ruiz J. · JAC-Antimicrobial Resistance (2025) · DOI: 10.1093/jacamr/dlaf089

Resumen

Background: The blaSCO-1 gene, which codes for a carbenicillinase, is an uncommon β-lactamase. To the best of our knowledge, we report the first instance of a Klebsiella pneumoniae clinical high-risk isolate carrying blaSCO-1 in Peru. Objectives: To characterize a K. pneumoniae clinical isolate carrying blaSCO-1 in Peru, isolated from a tertiary care hospital in Lima, Peru. Methods: Susceptibility to amoxicillin/clavulanic acid, amoxicillin/sulbactam, piperacillin/tazobactam, aztreonam, ceftriaxone, cefotaxime, ceftazidime, ceftazidime/avibactam, cefepime, imipenem, meropenem, ciprofloxacin, trimethoprim/sulfamethoxazole, gentamicin, amikacin and tigecycline was determined using the Kirby–Bauer disc diffusion method. Detection of blaSCO-1 was established by Illumina WGS and bioinformatic analyses. All the publicly available genomes from K. pneumoniae carrying blaSCO-1 from the American continent were downloaded from the NCBI Isolates browser for assessment of phylogenetic comparisons. Results: The isolate showed resistance to all the tested antibiotics except for ceftazidime/avibactam, carbapenems and tigecycline. Illumina WGS showed the presence of blaSCO-1 and blaOXA-1, blaSHV-28, blaTEM-1, blaCTX-M-15, as well as genes associated with resistance to quinolones, fosfomycin, aminoglycosides, sulphonamides, trimethoprim and phenicols. Moreover, the isolate was ST307, a high-risk clone of K. pneumoniae usually associated with blaCTX-M-15 and/or carbapenemases. Notwithstanding, the latter were not found on this isolate. Phylogenetic relationships were established by comparisons with 19 K. pneumoniae genomes carrying blaSCO-1 from other countries in the Americas, revealing at least three different clades. Conclusions: This study highlights the importance of genomic surveillance of uncommon antimicrobial resistance genes such as blaSCO-1, which might contribute to further antimicrobial resistance levels in this country. © The Author(s) 2025. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy.

Instituciones: Universidad Nacional Mayor de San Marcos; Universidad Científica del Sur; Universidad Privada San Juan Bautista