Phenotypic and genotypic characterization of macrolide-resistant group A Streptococcus strains in the province of Quebec, Canada.
Resistance to macrolides among group A streptococci is an increasing problem worldwide. We examined 496 strains phenotypically and genotypically for resistance to erythromycin and clindamycin. Strains were isolated in five different geographical areas representing about 45% of the total Quebec population. The overall resistance rate was 4.6% but varied from 0% in rural areas to 9.4% in Montreal. Of the 23 strains showing resistance to erythromycin, 15 (65%) had an identical pulsed-field gel electrophoresis pattern, were of serotype M28T28 and harboured the erm(TR) gene, suggesting the spread of a single clone. Of the remaining eight strains, two strains had the erm(B) gene, five had the mef gene and one with a different serotype also had the erm(TR) gene.
Hôpital Maisonneuve-Rosemont, University of Montreal, Montreal, Quebec, Canada H1T 2M4. weisscan@aol.com
K
K
Weiss
J
J
De Azavedo
C
C
Restieri
L A
LA
Galarneau
M
M
Gourdeau
P
P
Harvey
J F
JF
Paradis
K
K
Salim
D E
DE
Low
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins; D017931:DNA Primers; D004269:DNA, Bacterial / Q000235:genetics; D004352:Drug Resistance, Microbial; D016521:Electrophoresis, Gel, Pulsed-Field; D005838:Genotype; D006801:Humans; D018942:Macrolides; D008565:Membrane Proteins / Q000235:genetics; D008780:Methyltransferases / Q000235:genetics; D008826:Microbial Sensitivity Tests; D010612:Pharyngitis / Q000382:microbiology; D010641:Phenotype; D011792:Quebec; D013297:Streptococcus pyogenes / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D017931:DNA Primers; D004269:DNA, Bacterial; D018942:Macrolides; C117866:MefA protein, Streptococcus; D008565:Membrane Proteins; C111078:ErmTR protein, bacteria; D008780:Methyltransferases; C035181:rRNA (adenosine-O-2'-)methyltransferase