Introduction: MatrixÂ–assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) is known as a successful tool for bacterial identification and suitable for clinical diagnostics. The aim of our study was to evaluate diagnostic accuracy of MALDI-TOF MS system and VITEK Gram Positive Identification (GP ID) system for the identification of for Identification of Beta Hemolytic Streptococci (BHS).
Materials and Methods: A total 148 BHS isolates were included in the study. Isolates were identified by Bruker Biotyper 3.4 with VITEK 2 GP ID coupled to the agglutination test.
Results: BHS isolates were defined as Streptococcus pyogenes (n: 69), Streptococcus agalactiae (n: 59), Streptococcus dysgalactiae serogroup C (n: 5), and Streptococcus dysgalactiae serogroup G (n: 15) according to latex agglutination assay. MALDI-TOF MS analysis of 148 BHS isolates yielded correct identification for 100.0% of S. pyogenes, 100.0% of S. agalactiae, and 95.0% S. dysagalactiae serogroup C and G; while VITEK 2 GP ID gave correct identification for 88.4% of S. pyogenes, 93.2% of S. agalactiae, and 65.0% of S. dysagalactiae serogroup C and G.
Conclusions: MALDI-TOF MS-based identiﬁcation provides much cheaper, faster, and more accurate identiﬁcation of beta-hemolytic streptococcal species than VITEK 2 GP ID system.
MALDI-TOF;VITEK;Beta Hemolytic Streptococci;S. pyogenes;S. agalactiae;S. dysagalactiae