Editorial Commentary: Fluoroquinolone Prophylaxis in Patients with Neutropenia

Since the early report, by Karp et al. [1], of the beneficial effects of norfloxacin on the incidence of bacteremia and other bacterial infections in patients with neutropenia and cancer, the use of fluoroquinolones as prophylactic agents has been controversial. The results of 2 meta-analyses more or less agreed that these antibiotics reduced the incidence of gram-negative rod bacteremia, as well as episodes of fever [2, 3]. However, no study has truly demonstrated a definitive benefit with regard to infection-related mortality or, for that matter, to the outcome of treatment of the underlying malignancy. During the past 15 years, the use of fluoroquinolones to prevent infections in patients with neutropenia has varied in different parts of the world. The past 2 versions of the Infectious Diseases Society of America guidelines for the use of antimicrobial agents for patients with neutropenia and cancer failed to recommend these (or other antibacterial) agents for routine use in the prevention of bacterial infections [4, 5]. However, many European cancer centers have used these agents routinely, and this has been credited with reducing the frequency of gram-negative rod bacteremia and contributing to the shift toward gram-positive coccal bacteremia that had been recognized 10–15 years ago, although gram-negative bacteria have reemerged more recently [6, 7]. Well-documented evidence of significant increases in fluoroquinolone resistance among Escherichia coli strains has been published by researchers at many health care centers in Europe, including by a group in Ulm, Germany, who present an interesting and challenging article in this issue of Clinical Infectious Diseases [8].