Carbapenem antibiotic stress increases bla KPC -2 gene relative copy number and bacterial resistance levels of Klebsiella pneumoniae.

Carbapenem-resistant Klebsiella pneumoniae isolates may have multiple pathways to achieve high levels of carbapenem resistance, and moderate carbapenem pressure can increase the copy number of KPC enzyme genes in CRKP strains and enhance the degree of carbapenem resistance in the strains.