J Med Microbiol Email Content Delivery
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Bae, S. Y.
Right arrow Articles by Lee, C. K.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Bae, S. Y.
Right arrow Articles by Lee, C. K.
Agricola
Right arrow Articles by Bae, S. Y.
Right arrow Articles by Lee, C. K.
J Med Microbiol 56 (2007), 229-235; DOI: 10.1099/jmm.0.46825-0
© 2007 Society for General Microbiology
ISSN 1473-5644

Phenotypes and genotypes of macrolide-resistant Streptococcus pyogenes isolated in Seoul, Korea

Sook Young Bae, Jang Su Kim, Jung-Ah Kwon, Soo-Young Yoon, Chae Seung Lim, Kap No Lee, Yunjung Cho, Young Kee Kim and Chang Kyu Lee

Department of Laboratory Medicine, Korea University College of Medicine, Seoul, Republic of Korea

Correspondence
Chang Kyu Lee
cklee{at}korea.ac.kr

Received 9 July 2006
Accepted 25 October 2006

The mechanisms of resistance to macrolides in 51 erythromycin-resistant clinical isolates of Streptococcus pyogenes collected from 1997 through 2003 in Seoul, Korea were evaluated. They were characterized by their antimicrobial susceptibility, phenotype (using triple-disc and induction tests), resistance genotype, emm genotyping (M typing) and phylogenetic analysis. Erythromycin resistance was observed in 23 % of isolates. Inducible phenotype was the most common (iMLS, 51 %, 26 strains), followed by the constitutive phenotype (cMLS, 31 %, 16 strains) and the M phenotype (18 %, 9 strains). Eight of twenty-six iMLS isolates exhibited the iMLS-C phenotype. The remaining 18 isolates gave small inhibition zones (<12 mm) around all three discs, and mild blunting of the spiramycin and clindamycin zones of inhibition proximal to the erythromycin disc. They showed remarkable inducibility in erythromycin and clindamycin resistance. The MIC90 of erythromycin and clindamycin rose from 8 to >128 µg ml–1 and from 0.5 to >128 µg ml–1, respectively. Their resistance characteristics did not fit into any known iMLS subtype reported so far in the literature. So, it was named as an iMLS-D, new subtype. All of these iMLS-D strains harboured the erm(B) gene, demonstrated the emm12 genotype, except one, and formed a tight cluster in a phylogenetic tree, with 89.2 to 100 % sequence homology, suggesting that they are closely related. Nine of sixteen cMLS strains had the emm28 genotype, which had been reported to be associated with multiple drug resistance.

Abbreviations: MLS, macrolides lincosamides and streptogramin B.






HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
INT J SYST EVOL MICROBIOL J MED MICROBIOL MICROBIOLOGY J GEN VIROL ALL SGM JOURNALS
Copyright © 2007 Society for General Microbiology.