Xiao D1, You Y, Bi Z, Wang H, Zhang Y, Hu B, Song Y, Zhang H, Kou Z, Yan X, Zhang M, Jin L, Jiang X, Su P, Bi Z, Luo F, Zhang J. MALDI-TOF mass spectrometry-based identification of group A Streptococcus isolated from areas of the 2011 scarlet fever outbreak in china.Infect Genet Evol. 2013 Mar;14:320-6.
Abstract
There was a dramatic increase in scarlet fever cases in China from March to July 2011. Group A Streptococcus (GAS) is the only pathogen known to cause scarlet fever. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) coupled to Biotyper system was used for GAS identification in 2011. A local reference database (LRD) was constructed, evaluated and used to identify GAS isolates. The 75 GAS strains used to evaluate the LRD were all identified correctly. Of the 157 suspected β-hemolytic strains isolated from 298 throat swab samples, 127 (100%) and 120 (94.5%) of the isolates were identified as GAS by the MALDI-TOF MS system and the conventional bacitracin sensitivity test method, respectively. All 202 (100%) isolates were identified at the species level by searching the LRD, while 182 (90.1%) were identified by searching the original reference database (ORD). There were statistically significant differences with a high degree of credibility at species level (χ(2)=6.052, P