Activity of gatifloxacin tested against isolates from pediatric patients: report from the SENTRY Antimicrobial Surveillance Program (North America, 1998–2003)

The SENTRY Antimicrobial Surveillance Program has monitored the activity of antimicrobial agents worldwide since 1997. The increasing number of clinical failures with established anti-infectives (penicillins, other β-lactams, macrolides) among pediatric patients has stressed the importance for alternative therapeutic options. Ciprofloxacin has been recently approved for expanded use as treatment of complicated urinary tract infections in children, and gatifloxacin has been used successfully in clinical trials in selected children with severe or refractory otitis media. We evaluated the activity of gatifloxacin against strains isolated from children <7 years of age and compared this to the general patient population (all ages included) using the SENTRY Program database. A total of 59 826 North American isolates were collected, of which 4641 were from children (<7 years old); all isolates were tested using reference broth microdilution methods. In contrast to the general population (GP), gatifloxacin resistance rates were very low among isolates from this younger patient group. Gatifloxacin susceptibility rates were >84% for all pathogens evaluated in younger patients. All Streptococcus pneumoniae strains from children <7 years old were susceptible to gatifloxacin, and susceptibility among the Enterobacteriaceae species was >98%. The greatest difference in susceptibility rates between the younger children and the GP was observed among nonfermentative Gram-negative bacilli (95.0–100% versus 64.8–83.7%, respectively) and Enterococcus faecalis (94.7% versus 58.4%). Gatifloxacin susceptibilities of Pseudomonas aeruginosa and Acinetobacter spp. isolates from the pediatric population were ≥95% (>97% for ciprofloxacin) compared to the GP at only 64.8–69.1%. In conclusion, gatifloxacin remains very active against bacterial isolates from children <7 years, indicative of the limited exposure of this population to fluoroquinolones. Continued resistance surveillance will be necessary to monitor the activity of the fluoroquinolone class as they are introduced for specific clinical indications into the pediatric age groups, especially if re-studied against S. pneumoniae (refractory otitis media) and P. aeruginosa (cystic fibrosis associated pneumonia).