Novel KPC-2 Plasmid in a Clinical Salmonella Rissen Selected by Antibiotic Pressure

Abstract In this work, we present the genomic characterization of a clinical Salmonella enterica serovar Rissen isolate harboring a novel IncN2 plasmid carrying the blaKPC-2 gene. The identified plasmid (pSEay-KPC) also encoded additional resistance genes, including blaACC-1, blaTEM-1, and qnrB. The pSEay-KPC conferred broad-spectrum antimicrobial resistance, allowing the pathogen to survive two consecutive antibiotic therapies with ceftriaxone and ciprofloxacin. Effective treatment was ultimately achieved with meropenem–vaborbactam, a last-resort agent. These findings highlight IncN2 plasmids as potent vectors for the spread of clinically significant resistance genes, enabling bacteria to evade frontline antimicrobials and complicating infection management.