Korean J Clin Microbiol.  1999 Sep;2(2):131-134.

Erythromycin Resistance Phenotype of Streptococcus pyogenes

• Uh Y
• Hwang GY
• Jang IH
• Park JS
• Kwon OG
• Yoon KJ

Abstract

BACKGROUND: The erythromycin-resistance rate and phenotype distribution of Streptococcus propenes are quite different by geographical variation and study period. The aim of the present study was to determine the evolution of resistance to erythromycin and the frequency of erythromycin resistance phenotype of S. pyogenes isolated from Wonju Christian Hospital.
METHODS
The minimal inhibitory concentrations (MICs) of erythromycin and clindamycin for 94 S. pyogenes isolated from clinical specimens between 1990 to 1998 were investigated. Double disk test of erythromycin (78microgram) and clindamycin (25microgram) were performed for 15 isolates of erythromycin resistant S. pyogenes to evaluate the erythromycin resistance phenotype.
RESULTS
The resistance rates of 94 isolates of S. pyogenes were 16%(15/94) to erythromycin and 4%(4/94) to clindamycin. The frequency of erythromycin resistance phenotype in decreasing order were M phenotype (47%), inducible resistance phenotype (40%), and constitutive resistance phenotype (13%). Erythromycin-resistant S. pyogenes did not exist until 1993, but was isolated since 1994, and ranged from 14.0% to 24.0% during the period of 1994-1998.
CONCLUSIONS
Our finding documents the emergence of high resistance rates to erythromycin in S. pyogenes at Wonju area since 1994. The M phenotype (47%) and inducible resistance phenotype (40%) account for the majority of erythromycin-resistant S. pyogenes.

Keyword

Streptococcus pyogenes; Erythromycin resistance; Clindamycin resistance; Resistance phenotype

MeSH Terms

Clindamycin
Erythromycin*
Gangwon-do
Phenotype*
Streptococcus pyogenes*
Streptococcus*
Clindamycin
Erythromycin