Telithromycin and quinupristin-dalfopristin resistance in clinical isolates of Streptococcus pyogenes: SMART Program 2001 Data.
This study evaluated the current status of antimicrobial resistance in clinical isolates of Streptococcus pyogenes in Taiwan as part of the SMART (Surveillance from Multicenter Antimicrobial Resistance in Taiwan) program. In 2001, 419 different isolates of S. pyogenes, including 275 from respiratory secretions, 87 from wound pus, and 31 from blood, were collected from nine hospitals in different parts of Taiwan. MICs of 23 antimicrobial agents were determined at a central location by the agar dilution method. All of the isolates were susceptible to penicillin (MIC at which 90% of the isolates were inhibited [MIC(90)], <or=0.03 microg/ml), cefotaxime (MIC(90), <or=0.03 microg/ml), cefepime (MIC(90), 0.06 microg/ml), meropenem (MIC(90), <or=0.03 microg/ml), moxifloxacin (MIC(90), 0.25 microg/ml), vancomycin (MIC(90), 0.5 microg/ml), and linezolid (MIC(90), 1 micro g/ml). Overall, 78% of isolates were not susceptible to erythromycin (54% were intermediate, and 24% were resistant), and 5% were not susceptible to clindamycin. Of the 101 erythromycin-resistant isolates, 80.2% exhibited the M phenotype (mefA gene positive), 18.9% exhibited the cMLS (constitutive resistance to macrolides-lincosamides-streptogramin B [MLS]) phenotype (ermB gene positive), and 1% exhibited the iMLS (inducible resistance to MLS) phenotype (ermB gene positive). Fluoroquinolones (sitafloxacin > moxifloxacin > ciprofloxacin = levofloxacin = gatifloxacin > gemifloxacin) demonstrated potent activity against nearly all of the isolates of S. pyogenes tested. Thirty-two isolates (8%) were not susceptible to quinupristin-dalfopristin. Seventeen percent of isolates had telithromycin MICs of >or=1 microg/ml, and all of these isolates exhibited erythromycin MICs of >or=32 microg/ml. The high prevalence of resistance to telithromycin (which is not available in Taiwan) limits its potential use in the treatment of S. pyogenes infections, particularly in areas with high rates of macrolide resistance.
Hsueh
Po-Ren
PR
Departments of Laboratory Medicine and Internal Medicine, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei, Taiwan. hsporen@ha.mc.ntu.edu.tw
Teng
Lee-Jene
LJ
Lee
Chun-Ming
CM
Huang
Wen-Kuei
WK
Wu
Tsu-Lan
TL
Wan
Jen-Hsien
JH
Yang
Dine
D
Shyr
Jainn-Ming
JM
Chuang
Yin-Ching
YC
Yan
Jing-Jou
JJ
Lu
Jang-Jih
JJ
Wu
Jiunn-Jong
JJ
Ko
Wen-Chien
WC
Chang
Feng-Yee
FY
Yang
Yi-Chueh
YC
Lau
Yeu-Jun
YJ
Liu
Yung-Ching
YC
Leu
Hsieh-Shong
HS
Liu
Cheng-Yi
CY
Luh
Kwen-Tay
KT
D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D024881:Drug Resistance, Bacterial; D004917:Erythromycin / Q000627:therapeutic use; D005798:Genes, Bacterial; D006801:Humans; D048628:Ketolides; D018942:Macrolides; D008826:Microbial Sensitivity Tests; D010641:Phenotype; D013290:Streptococcal Infections / Q000188:drug therapy* / Q000453:epidemiology; D013297:Streptococcus pyogenes / Q000187:drug effects* / Q000235:genetics; D013624:Taiwan / Q000453:epidemiology; D014769:Virginiamycin / Q000031:analogs & derivatives* / Q000627:therapeutic use*
D000900:Anti-Bacterial Agents; D048628:Ketolides; D018942:Macrolides; D014769:Virginiamycin; C113825:quinupristin; D004917:Erythromycin; C106791:telithromycin; C113826:dalfopristin