Will a Reduction in Community Prescribing of Quinolones Decrease the Prevalence of Quinolone Resistance?

(See the article by Gottesman et al, on pages 869–75.) Worldwide use of fluroquinolones for 2 decades has resulted in increasing preva-lence of resistance [1, 2] and the emer-gence of plasmid-mediated resistance mechanisms [3]. Resistance in bacteria that cause community-acquired infections arises because of selection pressure from antibiotic use in hospitals, primary care facilities, or animals combined with the spread of resistance mechanisms among bacteria [2]. Most of the evidence that links community antibiotic use with re-sistance is observational and, therefore, is particularly susceptible to bias and con-founding [4]. Nonetheless, a strong sta-tistical association exists, and the consis-tency of evidence supports a cause-effect relationship [4]. The strongest scientific evidence comes from studies that sample individual patients before and after treat-ment; these studies show that even tran-sient exposure to antibiotics substantially increases the risk of isolation of antibiotic-resistant bacteria from the normal flora [5, 6]. Mathematical models of the relation