Abstract
Macrolide-resistance was assessed in 216 consecutive
Streptococcus pyogenes
isolates from throat infections in the region of Aachen, Germany. Seventeen isolates were resistant to erythromycin: 12
isolates revealed a macrolide (M) phenotype and harbored
mefA
, and five strains expressed an inducible macrolide-lincosamide-streptogramin B (MLS
B
) phenotype of which four strains harbored
ermA(TR)
and one strain contained
ermB(AM)
. Telithromycin (HMR 3647) and quinupristin/dalfopristin remained active particularly against the
erm
A(TR)-containing
S. pyogenes
isolates
studied. Random amplified polymorphic DNA analysis identified multiple clones among erythromycin-resistant strains, but did not discriminate beyond the
emm
-type.
mefA
was present in three
isolates either with
emm
2,
emm
12, or
emm
75, and in nine isolates with
emm
4. All four strains with
ermA(TR)
contained
emm
77, and the single strain with
ermB(AM)
harbored
emm
1. Despite the relative low rate of macrolide-resistance, these data suggest that at least three different macrolide-resistance determinants are prevalent in Germany and that
mefA
has spread rapidly into multiple clones of
S. pyogenes
.