Fluoroquinolone-resistantStreptococcus pneumoniae

Mathias W.R Pletz,Tobias Welte,Keith P Klugman,Lesley Mcgee,Jeffery J Glasheen,Darcie L Keller,Randolph V Fugit

doi:10.3201/eid1209.051400

Abstract

Fluoroquinolone-resistant<i>Streptococcus pneumoniae</i>

Highlights

To the Editor: In pneumococci, resistance to fluoroquinolones is associated with chromosomal mutations in the quinolone-resistance–determining regions (QRDR) of type II topoisomerase enzymes, predominantly gyrA and parC
We sequenced the QRDRs and the entire gyrA and parC genes of the resistant strain isolated from blood by using previously described primers [2]
Sequencing of the entire gyrA and parC genes confirmed that no additional amino acid substitutions were outside the QRDRs

Summary

Introduction

To the Editor: In pneumococci, resistance to fluoroquinolones is associated with chromosomal mutations in the quinolone-resistance–determining regions (QRDR) of type II topoisomerase enzymes, predominantly gyrA and parC. He had been discharged from the hospital 2 days earlier, having recovered from a similar manifestation of this disease. The isolate from blood was resistant to levofloxacin (MIC 8 mg/L) and ciprofloxacin (MIC 8 mg/L), yet susceptible to gatifloxacin (MIC 1 mg/L) and ceftriaxone (MIC 0.38 mg/L), with intermediate resistance to penicillin (MIC 1.5 mg/L).

Results

Conclusion