Emergence of Klebsiella pneumoniae ST258 with KPC-2 in Poland

Plasmidic KPC β-lactamases in gram-negative pathogens are of the highest clinical and epidemiologic concern, conferring resistance to all β-lactams, including carbapenems (15, 18). The main KPC producer is Klebsiella pneumoniae, but other species are being identified as well (15). Strains with KPCs spread rapidly and cause outbreaks; in hospitals on the east coast of the United States and in Israel, they have already become endemic (2, 3, 10, 14, 17). Recently, more countries have reported the presence of these organisms, in some cases as a result of importation (15).