We previously described flouroquinolone resistance is an isolate of Streptococcus pyogenes isolated in our laboratory from the blood of an NIH patient. In the current study we will determine the frequency of fluoroquinolone resistance among S. pyogenes isolates from Chicago. We will sequence the gyrA and parC genes of these isolates to determine the point mutations responsible for the fluoroquinolone resistance. Isolates are screened for resistance using a panel of antibiotic disks (Kirby-Bauer method) and the resistance is confirmed with a minimum inhibitory concentration method (eTest). Among 93 isolates we identified 10 isolates with varying degrees of fluoroquinolone resistance. We are currently screening another 89 isolates. All resistant isolates will be sequenced using the primer sets described in our previous publication.
