Nosocomial spread of Klebsiella pneumoniae isolates producing blaGES-4 carbapenemase at a Japanese hospital

Six Klebsiella pneumoniae clinical isolates resistant to various cephalosporins and cephamycins were identified in a Japanese general hospital, a tertiary care hospital, between November 2009 and April 2010. All K. pneumoniae isolates carried bla(GES-4) and bla(SHV-1), while 2 K. pneumoniae isolates also harbored bla(CTX-M-15). The pulsed-field gel electrophoresis patterns revealed that these 6 K. pneumoniae isolates were almost identical, suggesting their clonal relatedness. Plasmid profiles and conjugation assays revealed that these bla(GES-4) genes were located on similar conjugative plasmids. These data indicate that nosocomial spread caused by K. pneumoniae isolates producing bla(GES-4) carbapenemase occurred at a Japanese general hospital. K. pneumoniae isolate harboring bla(GES-4) is rarely reported in Japan, and, to the best of our knowledge, this is the second report of K. pneumoniae isolates harboring bla(GES-4) that occurred nosocomial spread in Japan. (C) 2016 Published by Elsevier Ltd on behalf of Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases.