Background: A surveillance system for antibiotic resistance is well organized in both Japan and Korea; however, a comparative analysis by microorganism has not previously been conducted.

Methods: We compared the latest antibiotic resistance rates of medically important pathogens, such as Staphylococcus aureus, enterococci, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii, between Japan and Korea. Data were collected by JANIS (Japan Nosocomial Infections Surveillance) and KARMS (Korean Antimicrobial Resistance Monitoring System) from 2007-2012.

Results: In 2012, the proportions of oxacillin-resistant S. aureus, vancomycin-resistant Enterococcus faecium (VRE), cefotaxime-resistant E. coli, ceftazidime-resistant K. pneumoniae, imipenem-resistant P. aeruginosa, and imipenem-resistant A. baumannii were 53%, 0.4%, 16.6%, 2.9%, 18.5%, and 2% in Japan and 67%, 32%, 29%, 40%, 28%, and 70% in Korea, respectively.

Conclusion: There were large differences in the frequencies of VRE, ceftazidime-resistant K. pneumoniae, and imipenem-resistant A. baumannii between Japan and Korea. A collaborative study to probe the differences in the antibiotic resistance rates between the two countries should be performed. (Ann Clin Microbiol 2015;18:111-118)