Rapid inversion of the prevalences of macrolide resistance phenotypes paralleled by a diversification of T and emm types among Streptococcus pyogenes in Portugal.
In Portugal erythromycin resistance of 26.6% (n = 352) remained constant during 1998 to 2003, however in 1998 the MLS(B) phenotype dominated (85%), whereas in 2003 the M phenotype prevailed (77%). A decline in T12/emm22 MLS(B) isolates could partially explain the drop in this phenotype, but the rise of the M phenotype was not due to clonal expansion.
Silva-Costa
C
C
Laboratory of Microbiology, Institute of Molecular Medicine, Lisbon Faculty of Medicine, Av. Prof. Egas Moniz, PT 1649-028 Lisboa, Portugal.
Ramirez
M
M
Melo-Cristino
J
J
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics*; D024881:Drug Resistance, Bacterial; D006801:Humans; D018942:Macrolides / Q000494:pharmacology*; D008565:Membrane Proteins / Q000235:genetics*; D010641:Phenotype; D011174:Portugal / Q000453:epidemiology; D013290:Streptococcal Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology; D013297:Streptococcus pyogenes / Q000187:drug effects* / Q000235:genetics*; D013753:Tetracycline Resistance
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; C087175:Emm22 protein,Streptococcus pyogenes; D018942:Macrolides; D008565:Membrane Proteins