It remains unclear why the ST258 lineage is the most prevalent cause of multidrug resistant K. pneumoniae infections in the United States and other countries. To that end, we continued our research directed to better understand of the basis for the success of ST258. These studies included further analysis of region of recombination that encompasses the genes encoding capsule polysaccharide biosynthesis machinery. In addition, we studied the interaction of carbapenem-resistant Klebsiella pneumoniae (ST258) with human neutrophils to test the hypothesis that this strain has enhanced capacity to circumvent killing by the innate immune system. Our findings will accelerate research on novel diagnostic, therapeutic, and vaccine strategies designed to prevent and/or treat infections caused by multidrug resistant K. pneumoniae.