Short communication: Global clones of CTX-M-15-producing Enterobacterales, including the high-risk Enterobacter hormaechei ST78 in a veterinary teaching hospital.

Extended-spectrum β-lactamases (ESBLs), particularly CTX-M enzymes, represent a significant concern among Enterobacterales. This cross-sectional, descriptive study reports the first detection and genomic characterization of CTX-M-15-producing Enterobacter hormaechei and Leclercia adecarboxylata recovered from high-contact surfaces in a Brazilian veterinary teaching hospital, based on analysis of 12 environmental samples. Three multidrug-resistant isolates were identified: E. hormaechei ST78 (UFRGS-TABLE-2023), E. hormaechei ST68 (UFRGS-TAP-2023), and L. adecarboxylata (UFRGS-BED-2023), all carrying blaCTX-M-15, blaTEM-1B, blaOXA-1, and additional resistance genes to aminoglycosides, quinolones, sulfonamides, and tetracyclines. IncHI2 plasmids harboring blaCTX-M-15 were detected in UFRGS-BED-2023 and UFRGS-TAP-2023 and showed high sequence similarity to a previously described human E. hormaechei plasmid. Phylogenomic analysis placed the isolates within globally distributed lineages. Although descriptive in nature and not intended to infer prevalence or transmission dynamics, these findings highlight veterinary hospital surfaces as potential reservoirs of antimicrobial resistance and support the need for integrated One Health surveillance.