BACKGROUND. Streptococcus agalactiae remains susceptible to penicillin; nevertheless, an increase in the resistance to other antimicrobial families, such as macrolides and more rarely fluoroquinolones, has been described. METHODS AND RESULTS. From 2003 to 2004, two fluoroquinolone-resistant S. agalactiae strains were detected. The strains presented one mutation in parC (Ser 79 → Phe) and an additional mutation in gyrA (Glu 85 → Ala or Glu 85 → Lys). CONCLUSION. This study describes the first S. agalactiae strains highly resistant to fluoroquinolones in Spain.
- Streptococcus agalactiae