Fluoquinolone resistance in Streptococcus pneumoniae

Abstract

To the Editor: Chen et al. (July 22 issue) report an increasing prevalence of Streptococcus pneumoniae strains with reduced susceptibility to fluoroquinolones in Canada. We have found similar results in Barcelona, Spain.Of 2822 pneumococcal isolates studied in our institution from 1991 through 1998, 57 (2.0 percent) were resistant to ciprofloxacin (minimal inhibitory concentration, ≥4 μg per milliliter). We have seen an increase of ciprofloxacin-resistant pneumococci, from 0.9 percent (6 of 675 strains) in 1991-1992 to 3.0 percent (22 of 727 strains) in 1997-1998 (P=0.004).