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International quality assurance study for characterization of Streptococcus pyogenes

Neal, Shona; Beall, Bernard; Ekelund, Kim; Henriques-Normark, Birgitta; Jasir, Aftab LU ; Johnson, Dwight; Kaplan, Edward; Lovgren, Marguerite; Reinert, Ralf Rene and Efstratiou, Androulla (2007) In Journal of Clinical Microbiology 45(4). p.1175-1179
Abstract
Surveillance of group A streptococcal (GAS) infections was undertaken as a major component of the European Commission-funded project on severe GAS disease in Europe (strep-EURO). One aim of strep-EURO was to improve the quality of GAS characterization by standardization of methods. An external quality assurance study (EQA) was therefore carried out to evaluate current global performance. Eleven strep-EURO and seven other streptococcal reference centers received a panel of 20 coded GAS isolates for typing. Conventional phenotypic typing (based on cell surface T and M protein antigens and opacity factor [OF] production) and molecular methods (emm gene typing) were used either as single or combined approaches to GAS typing. T typing was... (More)
Surveillance of group A streptococcal (GAS) infections was undertaken as a major component of the European Commission-funded project on severe GAS disease in Europe (strep-EURO). One aim of strep-EURO was to improve the quality of GAS characterization by standardization of methods. An external quality assurance study (EQA) was therefore carried out to evaluate current global performance. Eleven strep-EURO and seven other streptococcal reference centers received a panel of 20 coded GAS isolates for typing. Conventional phenotypic typing (based on cell surface T and M protein antigens and opacity factor [OF] production) and molecular methods (emm gene typing) were used either as single or combined approaches to GAS typing. T typing was performed by 16 centers; 12 centers found one or more of the 20 strains nontypeable (typeability, 89%), and 11 centers reported at least one incorrect result (concordance, 93%). The 10 centers that tested for OF production achieved 96% concordance. Limited availability of antisera resulted in poor typeability values from the four centers that performed phenotypic M typing (41%), three of which also performed anti-OF typing (typeability, 63%); however, concordance was high for both M (100%) and anti-OF (94%) typing. In contrast, the 15 centers that performed emm gene sequencing achieved excellent typeability (97%) and concordance (98%), although comparison of the performance between centers yielded typeability rates from 65 to 100% and concordance values from 83 to 100%. With the rapid expansion and use of molecular genotypic methods to characterize GAS, continuation of EQA is essential in order to achieve international standardization and comparison of type distributions. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Clinical Microbiology
volume
45
issue
4
pages
1175 - 1179
publisher
American Society for Microbiology
external identifiers
  • wos:000245779300015
  • scopus:34247243311
ISSN
1098-660X
DOI
10.1128/JCM.02146-06
language
English
LU publication?
yes
id
1aaf09e3-72b8-480a-b097-34f831550073 (old id 665962)
date added to LUP
2007-12-13 16:22:47
date last changed
2017-01-01 07:09:14
@article{1aaf09e3-72b8-480a-b097-34f831550073,
  abstract     = {Surveillance of group A streptococcal (GAS) infections was undertaken as a major component of the European Commission-funded project on severe GAS disease in Europe (strep-EURO). One aim of strep-EURO was to improve the quality of GAS characterization by standardization of methods. An external quality assurance study (EQA) was therefore carried out to evaluate current global performance. Eleven strep-EURO and seven other streptococcal reference centers received a panel of 20 coded GAS isolates for typing. Conventional phenotypic typing (based on cell surface T and M protein antigens and opacity factor [OF] production) and molecular methods (emm gene typing) were used either as single or combined approaches to GAS typing. T typing was performed by 16 centers; 12 centers found one or more of the 20 strains nontypeable (typeability, 89%), and 11 centers reported at least one incorrect result (concordance, 93%). The 10 centers that tested for OF production achieved 96% concordance. Limited availability of antisera resulted in poor typeability values from the four centers that performed phenotypic M typing (41%), three of which also performed anti-OF typing (typeability, 63%); however, concordance was high for both M (100%) and anti-OF (94%) typing. In contrast, the 15 centers that performed emm gene sequencing achieved excellent typeability (97%) and concordance (98%), although comparison of the performance between centers yielded typeability rates from 65 to 100% and concordance values from 83 to 100%. With the rapid expansion and use of molecular genotypic methods to characterize GAS, continuation of EQA is essential in order to achieve international standardization and comparison of type distributions.},
  author       = {Neal, Shona and Beall, Bernard and Ekelund, Kim and Henriques-Normark, Birgitta and Jasir, Aftab and Johnson, Dwight and Kaplan, Edward and Lovgren, Marguerite and Reinert, Ralf Rene and Efstratiou, Androulla},
  issn         = {1098-660X},
  language     = {eng},
  number       = {4},
  pages        = {1175--1179},
  publisher    = {American Society for Microbiology},
  series       = {Journal of Clinical Microbiology},
  title        = {International quality assurance study for characterization of Streptococcus pyogenes},
  url          = {http://dx.doi.org/10.1128/JCM.02146-06},
  volume       = {45},
  year         = {2007},
}