title: Accuracy of in vitro susceptibility tests for carbapenemase-producing Gram-negative bacteria.
abstract: Accurate susceptibility results on antibiotic-resistant bacteria are essential for proper treatment of infections. In this study, 100 metallo-β-lactamase (MBL)-producing strains and 95 isolates with Klebsiella pneumoniae carbapenemase (KPC) were tested for carbapenem susceptibility using two automated platforms, the Phoenix and Vitek-2 systems, and a manual Etest. Phoenix showed higher categorical agreements (97% for imipenem and 94% for meropenem) compared with those from Vitek-2 (92 and 74%) and Etest (89 and 96%), respectively, when testing MBL strains. Categorical agreement for imipenem tests with KPC-producing strains was 88.4% with the Phoenix system, 83.2% with the Vitek 2 system and 90.5% with the Etest. Categorical agreement was 100% for all tests with ertapenem. In conclusion, the Phoenix system demonstrated a higher accuracy than Vitek-2 in testing carbapenemase-producing strains, particularly in MBL strains.
authors: Department of Clinical Microbiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200025, PR China.
authors: Jingyong
authors: J
authors: Sun
authors: Department of Clinical Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing 100730, PR China.
authors: Yingchun
authors: Y
authors: Xu
authors: Department of Infectious Diseases, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310016, PR China.
authors: Yunsong
authors: Y
authors: Yu
authors: Department of Clinical Microbiology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 200025, PR China.
authors: Yuxing
authors: Y
authors: Ni
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D057205:Automation, Laboratory / Q000379:methods; D001426:Bacterial Proteins / Q000378:metabolism*; D003951:Diagnostic Errors; D006090:Gram-Negative Bacteria / Q000187:drug effects* / Q000201:enzymology*; D006801:Humans; D008826:Microbial Sensitivity Tests / Q000379:methods*; D001618:beta-Lactamases / Q000378:metabolism*; D047090:beta-Lactams / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D047090:beta-Lactams; D001618:beta-Lactamases; C063912:carbapenemase