Which of the following statements about the fluoroquinolones is FALSE?: (A) Gonococcal resistance to fluoroquinolones may involve changes in DNA gyrase, (B) Modification of fluoroquinolones dosage is required in patients if creatinine clearance is less than 50 mL/min, (C) A fluoroquinolone is the drug of choice for treatment of an uncomplicated urinary tract infection in a 7 year-old girl, (D) Fluoroquinolones inhibit relaxation of positively supercoiled DNA
Answer is C. * Fluoroquinolones are contra-indicated in children (due to risk of cailage damage) and pregnant female. * Most common mode of resistance to fluoroquinolones is mutation in DNA gyrase. * Dose of fluoroquinolones should be adjusted in renal failure (except moxifloxacin and trovafloxacin). * These drugs act by inhibiting DNA gyrase.