title: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for the identification of beta-hemolytic streptococci.
abstract: OBJECTIVE
  Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has emerged as promising technology for species identification. The purpose of this investigation was to compare the performance of MS and the traditional method for identification of beta-hemolytic streptococci (BHS).
  
  
  METHODS
  Clinical BHS isolates were identified by the BD Phoenix SMIC/ID Streptococcal panels, and two MALDI-TOF MS platforms: the VITEK MS and the Bruker MALDI Biotyper systems respectively. In case of discordant results, 16sRNA sequencing was performed to provide the reference ID.
  
  
  RESULTS
  A total of 96 isolates of BHS were analyzed. Thirty-six isolates (20.8%) were re-tested by BD Phoenix for identification failure; and four isolates (4.2%) were rerun on the Bruker system for low identification score. No isolate need a second run for identification by Vitek MS system. Overall, BD Phoenix, BioTyper and Vitek MS automated system accurately identified 76 strains (79.2%), 91 (94.7%) strains and 92 (95.8%) strains, respectively.
  
  
  CONCLUSIONS
  Our study suggests that MALDI-TOF MS is a superior method to conventional phenotypic methods for BHS identification.
authors.affiliation: 1 Department of Clinical microbiology laboratory, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 2 Department of Respiratory Medicine, Huangdong Hospital, Fudan University, Shanghai 200040, China ; 3 Department of Respiratory Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 4 Department of Respiratory Medicine, Yingzhou Hospital, Ningbo University, Ningbo 315040, China.
authors.forename: Chunmei
authors.initials: C
authors.lastname: Zhou
authors.affiliation: 1 Department of Clinical microbiology laboratory, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 2 Department of Respiratory Medicine, Huangdong Hospital, Fudan University, Shanghai 200040, China ; 3 Department of Respiratory Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 4 Department of Respiratory Medicine, Yingzhou Hospital, Ningbo University, Ningbo 315040, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Tao
authors.affiliation: 1 Department of Clinical microbiology laboratory, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 2 Department of Respiratory Medicine, Huangdong Hospital, Fudan University, Shanghai 200040, China ; 3 Department of Respiratory Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 4 Department of Respiratory Medicine, Yingzhou Hospital, Ningbo University, Ningbo 315040, China.
authors.forename: Bijie
authors.initials: B
authors.lastname: Hu
authors.affiliation: 1 Department of Clinical microbiology laboratory, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 2 Department of Respiratory Medicine, Huangdong Hospital, Fudan University, Shanghai 200040, China ; 3 Department of Respiratory Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 4 Department of Respiratory Medicine, Yingzhou Hospital, Ningbo University, Ningbo 315040, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Ma
authors.affiliation: 1 Department of Clinical microbiology laboratory, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 2 Department of Respiratory Medicine, Huangdong Hospital, Fudan University, Shanghai 200040, China ; 3 Department of Respiratory Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 4 Department of Respiratory Medicine, Yingzhou Hospital, Ningbo University, Ningbo 315040, China.
authors.forename: Xiangru
authors.initials: X
authors.lastname: Ye
authors.affiliation: 1 Department of Clinical microbiology laboratory, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 2 Department of Respiratory Medicine, Huangdong Hospital, Fudan University, Shanghai 200040, China ; 3 Department of Respiratory Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 4 Department of Respiratory Medicine, Yingzhou Hospital, Ningbo University, Ningbo 315040, China.
authors.forename: Shenglei
authors.initials: S
authors.lastname: Huang
authors.affiliation: 1 Department of Clinical microbiology laboratory, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 2 Department of Respiratory Medicine, Huangdong Hospital, Fudan University, Shanghai 200040, China ; 3 Department of Respiratory Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 4 Department of Respiratory Medicine, Yingzhou Hospital, Ningbo University, Ningbo 315040, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.affiliation: 1 Department of Clinical microbiology laboratory, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 2 Department of Respiratory Medicine, Huangdong Hospital, Fudan University, Shanghai 200040, China ; 3 Department of Respiratory Medicine, Zhongshan Hospital, Fudan University, Shanghai 200032, China ; 4 Department of Respiratory Medicine, Yingzhou Hospital, Ningbo University, Ningbo 315040, China.
authors.forename: Yuzhang
authors.initials: Y
authors.lastname: Shan
keywords: MS; Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS); beta-hemolytic streptococci (BHS); identification