There has been a growing rate of resistance among common urinary tract pathogens, such as Escherichia coli, to traditional antimicrobial
therapies including the "gold standard"
trimethoprim-sulfamethoxazole (
TMP-SMX). Consequently,
fluoroquinolone antimicrobial agents have taken on an expanding management role for UTIs. In fact, the recent
Infectious Diseases Society of America clinical management guidelines for UTI recommend
fluoroquinolones as first-line
therapy for uncomplicated UTI in areas where resistance is likely to be of concern.
Fluoroquinolones have demonstrated high bacteriologic and clinical cure rates, as well as low rates of resistance, among most common uropathogens. There are currently 7
fluoroquinolones with indications for UTI in the United States. However, only 3 are commonly used:
levofloxacin,
ciprofloxacin, and, to a lesser extent,
gatifloxacin. Many of the
fluoroquinolone agents have once-daily dosing regimens, enhancing patient adherence. In addition,
levofloxacin and
gatifloxacin have same-dose bioequivalency between their intravenous and oral formulations, allowing for "switch" or step-down
therapy from parenteral to oral formulations of the same agent at the same dose.
Fluoroquinolones are indicated for the management of acute uncomplicated UTIs, as well as complicated and severe UTI and
pyelonephritis, in adults. They are the first-line treatment of acute uncomplicated
cystitis in patients who cannot tolerate
sulfonamides or
TMP, who live in geographic areas with known resistance >10% to 20% to
TMP-SMX, or who have risk factors for such resistance.
Fluoroquinolone properties include a broad spectrum of coverage, low rates of resistance, and good safety profiles.