Genetic and phenotypic characterization of resistance to macrolides in Streptococcus pyogenes from Argentina.
Five hundred and seventy-eight strains of group A streptococci (GAS) isolated mostly from paediatric pharyngeal swabs were tested to evaluate their susceptibility to erythromycin. Resistant strains were then tested for their MICs to erythromycin and clindamycin, their phenotype of resistance to macrolides-lincosamides-streptogramin (MLS(B)) and for the presence of macrolide resistance genes. The rate of resistance to erythromycin was 8.2%. Constitutive, inducible and M phenotypes of resistance were detected in 2.1, 2.1 and 95.8% of resistant strains, respectively. All M phenotypes harboured the mefA gene, whereas constitutive and inducible phenotypes had ermB and ermTR genes, respectively.
Martínez
Silvia
S
Escuela de Graduados, Carrera de Especialización en Bioquímica Clínica-área Bacteriología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.
Amoroso
Ana M
AM
Famiglietti
Angela
A
de Mier
Carmen
C
Vay
Carlos
C
Gutkind
Gabriel O
GO
D024881:Drug Resistance, Bacterial / Q000235:genetics*; D018942:Macrolides; D015337:Multicenter Studies as Topic; D010641:Phenotype; D013290:Streptococcal Infections / Q000188:drug therapy / Q000235:genetics / Q000382:microbiology*; D013297:Streptococcus pyogenes / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification
D018942:Macrolides