Widespread use of fluoroquinolones versus emerging resistance in pneumococci.

During the past decade, respiratory-tract pathogens have shown an increase in resistance to all classes of antimicrobial agents. Although the increasing prevalence of penicillin-resistant Streptococcus pneumoniae has resulted in an increased reliance on newer classes of agents, such as the fluoroquinolones, the broad use of these agents has contributed to increasing prevalence of strains with in vitro fluoroquinolone resistance, which are associated with treatment failures, nosocomial outbreaks, and patient fatalities. Strategies to limit this emerging dilemma and preserve the clinical utility of these agents are needed.