Antimicrobial agents and chemotherapy
-
Antimicrob. Agents Chemother. · Dec 2003
Randomized Controlled Trial Comparative Study Clinical TrialConcentrations in plasma, urinary excretion, and bactericidal activity of linezolid (600 milligrams) versus those of ciprofloxacin (500 milligrams) in healthy volunteers receiving a single oral dose.
In a randomized crossover study, 12 volunteers (6 males, 6 females) received a single oral dose of 600 mg of linezolid or 500 mg of ciprofloxacin to assess the concentrations in plasma (up to 24 h), urinary excretion (by high-pressure liquid chromatography), and bactericidal titers in urine (UBT) at intervals up to 120 h. The mean maximum concentration of linezolid in plasma was 13.1 mg/liter, and that of ciprofloxacin was 2.46 mg/liter. The median cumulative levels of renal excretion of the administered dose of the parent drug were 44% for linezolid (range, 28 to 47%; mean +/- standard deviation, 40% +/- 7.8%) and 43% for ciprofloxacin (range, 20 to 56%; mean +/- standard deviation, 40% +/- 9.3%). ⋯ For linezolid there were no statistically significant differences in UBTs or AUBTs for ciprofloxacin-susceptible and -resistant strains. Thus, the bactericidal activities of linezolid and ciprofloxacin against susceptible strains in urine were comparable, whereas linezolid also exhibited the same good bactericidal activity against ciprofloxacin-resistant strains. Therefore, linezolid should be tested for use as empirical treatment for complicated urinary tract infections due to gram-positive uropathogens in an appropriate clinical trial.
-
Antimicrob. Agents Chemother. · Dec 2003
Clinical TrialLinezolid penetration into bone and joint tissues infected with methicillin-resistant staphylococci.
Penetration of linezolid into bone and joint tissues was studied by high-performance liquid chromatography in 13 patients suffering from implant-associated infections with methicillin-resistant staphylococci. Mean concentrations of linezolid in infected tissues were greater than 10 mg/liter in a sampling time range of 35 to 124 min after administration of the preoperative dose, except in bone specimens, where they reached 3.9 +/- 2.0 mg/liter.