ABSTRACT
Objective To evaluate the application of partial cpsA-cpsB serotype prediction system as a serotyping method for streptococcus pneumonia.Methods Ninety-four isolates in this study were provided by Microorganism Research Room of Beijing Pediatric Research Institution,Beijing Children's Hospital Affiliated to Capital Medical University.The quelling test was applied to determine gold standard of serotypes of isolates.Polymerase chain reaction (PCR),sequencing,sequence data management and alignment were implemented previously.Results Eighty-three out of all 94 isolates were serotyped by quelling reaction,and 11 isolates were non-serotype isolates.Among the 83 isolates,67 (80.72％) isolates got positive PCR results and 60 (89.55％)isolates got results consistent with gold standard or containing gold standard.Among 12 isolates belonging to 19F,10 isolates were correctly predicted,and 2 isolates were predicted to be 6A,23F/10A.Among 19 isolates belonging to serotype 19A,1 isolate was predicted to be 35 F/47F,and the other 18 isolates were correctly predicted.Among 10 isolates belonging to serotype 14,9 isolates got results consistent with gold standard,and 1 isolate was predicted to be 19A.All 7 isolates belonging to serotype 6B were predicted to be 6A/6B and 4 isolates belonging to 23F were predicted to be 23F/10A.3 of 11 (27.27％) non-serotype isolates got positive PCR results and were predicted to be 6A/6C,6A/6B,19A.Conclusions Partial cpsA-cpsB sequencing system is a useful method for detecting streptococcus pneumoniae serotypes.