Volume 97, Issue 12 pp. 1681-1685

Characteristics of Streptococcus pyogenes strains isolated from Chinese children with scarlet fever

Yunmei Liang

Yunmei Liang

Beijing Children's Hospital, Affiliated to the Capital Medical University, Beijing, China

Search for more papers by this author
Xuzhuang Shen

Xuzhuang Shen

Beijing Children's Hospital, Affiliated to the Capital Medical University, Beijing, China

Search for more papers by this author
Guoying Huang

Guoying Huang

The Fudan University Children's Hospital, Shanghai, China

Search for more papers by this author
Chuanqing Wang

Chuanqing Wang

The Fudan University Children's Hospital, Shanghai, China

Search for more papers by this author
Ying Shen

Ying Shen

Beijing Children's Hospital, Affiliated to the Capital Medical University, Beijing, China

Search for more papers by this author
Yonghong Yang

Yonghong Yang

Beijing Children's Hospital, Affiliated to the Capital Medical University, Beijing, China

The Fudan University Children's Hospital, Shanghai, China

Search for more papers by this author
First published: 06 November 2008
Citations: 22
Correspondence
Professor Yonghong Yang, Beijing Children's Hospital, Affiliated to Capital Medical University, 56 South Lishi Road, Beijing 100045, China
Tel/Fax: + 86 10 68029020 |
Email: [email protected]

Abstract

Aim: To analyse the characteristics of Streptococcus pyogenes isolates from Chinese children with scarlet fever.

Methods: Minimal inhibitory concentration with nine antibiotics was performed on 145 Streptococcus pyogenes isolates acquired from Beijing and Shanghai in 2007. Their macrolide-resistant genes (mefA, ermB and ermA– a subclass of ermTR), superantigens (speA and speC), and en-coding mature M protein gene (emm gene) were amplified by PCR.

Results: A total of 97.9% of the isolates exhibited resistance to the macrolides, while 96.6% manifested resistance to tetracycline. All isolates were sensitive to chloramphenicol, penicillin, cefradine, and ofloxacin. Moreover, 94.5% exhibited a cMLSB phenotype, while 90.3% had the ermB gene. Five emm types (emm1.0, emm4.0, emm12.0, emm22.0 and st5240) were discovered, of which 9.7% carried the superantigen speA, 35.9% carried the speC, 42.8% carried both speA and speC and 11.7% carried neither speA nor speC. Finally, 85.5% of emm1.0 and 15.5% of emm12.0 isolates carried speA, while 79.0% of emm1.0 and 75.9% of emm12.0 isolates carried speC.

Conclusion: The Streptococcus pyogenes isolates had high resistance rates against macrolides and tetracycline. They mainly expressed the ermB gene type and cMLSB phenotype. Their common emm types are emm1.0 and emm12.0, which have different frequencies of speA and speC.

The full text of this article hosted at iucr.org is unavailable due to technical difficulties.