blaKPC

blaKPC, commonly written bla_KPC, is the gene encoding Klebsiella pneumoniae carbapenemase (KPC), a serine-based class A β-lactamase that neutralizes many β-lactam antibiotics, including carbapenems. Bacteria carrying bla_KPC often exhibit resistance to most penicillins and cephalosporins, and may resist multiple drug classes. The gene is typically located on plasmids and linked to transposable elements such as Tn4401, which enables horizontal transfer among Enterobacterales and other Gram-negative bacteria.

Multiple bla_KPC alleles have been identified, including bla_KPC-2, bla_KPC-3, bla_KPC-4, and bla_KPC-13, with minor sequence differences influencing expression levels and substrate profiles.

First described in 1996 in Klebsiella pneumoniae isolates from the United States; the KPC enzyme rapidly disseminated worldwide, becoming a major driver of carbapenem-resistant Enterobacterales (CRE) outbreaks, particularly in healthcare settings.

Detection relies on molecular assays—PCR tests targeting bla_KPC and sequencing. Phenotypic methods for carbapenemase production include the Carba NP test, modified Hodge test, and inhibitor-based tests that use boronic acid compounds to indicate KPC activity.

Clinical management is challenging; options include ceftazidime-avibactam and meropenem-vaborbactam, which retain activity against many bla_KPC producers. In some settings, aztreonam in combination with avibactam can be used for organisms with additional beta-lactamases. Infection-control measures and antimicrobial stewardship are essential to limit spread.