Invasive Klebsiella pneumoniae syndrome in North America.

Invasive liver abscess syndrome, which is caused by hypervirulent Klebsiella pneumoniae subtypes, has been emerging worldwide over the past 2 decades. The syndrome is associated with the hypermucoviscosity phenotype of K. pneumoniae strains and with the magA and rmpA genes. We provide the first laboratory evidence of the presence of rmpA-positive K. pneumoniae in North America.