Quinolone Resistance

Quinolone antibacterial agents were first introduced into the clinical environment in the early 1960s. The first qumolone to be clinically used was nalidixic acid, which was used for the treatment of enteric and urinary tract infections. As a result of increased clinical resistance to this drug, its use has declined. However, the development of other chemically related antimicrobials with activities approaching one thousand times that of nalidixic acid has meant that bacteria resistant to this early nonfluormated quinolone are susceptible to the action of the newer fluoroquinolones. The fluoroquinolones, such as ciprofloxacin and ofloxacin, have proved to be potent antimicrobials and are used throughout the world in the treatment of bacterial infections, ranging from urinary tract infections to life-threatening septicemia. The clinical success of these agents can be attributed to their broad spectrum of activity, unique mechanism of action, good tissue distribution, and absorption from the gastrointestinal tract after oral admmistration (1 ).