Molecular characterization of ST15 carbapenem-resistant Klebsiella pneumoniaeisolated in a single patient

•Continuous isolation of ST15 Klebsiella pneumoniaestrains from a single patient demonstrated an alternating resistance-sensitivity-resistance-sensitivity pattern to carbapenems throughout antibiotic therapy.•A plasmid p2-KP3762–1 harbouring the blaKPC-2and two blaTEM-1Bgenes was identified. It can transfer among CRKP to CSKP, hvKP and Escherichia coli, thereby rapidly disseminating the carbapenem resistance genes.•Despite long-term antibiotic treatment, the infectious pathogen remains culturable, exhibiting diverse phenotypes yet retaining closely related genetic backgrounds.