TRENDS IN BACTERIAL-RESISTANCE TO FLUOROQUINOLONES

The emergence of resistance to fluoroquinolones in virtually all speci es of bacteria was recognized soon after the introduction of these com pounds for clinical use more than 10 years ago. Various resistance mec hanisms, often interdependent, may explain different levels of resista nce. Epidemiological factors, local antibiotic policies, patients' cha racteristics, origin of the strains, and geographic location are among the factors contributing to highly variable resistance rates. During the last several years, resistance to fluoroquinolones has remained ve ry high among methicillin-resistant Staphylococcus aureus strains and in intensive care unit patients, and it has increased among nosocomial isolates of Klebsiella pneumoniae, Serratia marcescens, and Pseudomon as aeruginosa. More worrisome are recent reports of an overall increas e in resistance to fluoroquinolones among bacteria responsible,for com munity-acquired infections, such as Escherichia coli, Salmonella speci es, Campylobacter species and Neisseria gonorrhoeae.