Extracellular concentrations of fosfomycin in lung tissue of septic patients

The present investigation explored the ability of fosfomycin to penetrate lung tissue of septic patients by utilizing the microdialysis technique. After microdialysis probe insertion into healthy and infected lung tissue, a single intravenous dose of 4 g of fosfomycin was administered. The mean C(max), T(max), AUC(0-4) and AUC(0-infinity) for healthy lung were 131.6 +/- 110.6 mg/L, 1.1 +/- 0.4 h, 242.4 +/- 101.6 mg center dot h/L and 367.6 +/- 111.9 mg center dot h/L, respectively. The corresponding values for infected lung were 107.5 +/- 60.2 mg/L, 1.4 +/- 0.5 h, 203.5 +/- 118.4 mg center dot h/L and 315.1 +/- 151.2 mg center dot h/L. The half-life of fosfomycin ranged from 2.2 to 2.7 h between compartments. The magnitude of lung tissue penetration, as determined by the ratios of the AUC(0-infinity) for lung to the AUC(0-infinity) for plasma, was 0.63 +/- 0.31 and 0.53 +/- 0.31 for healthy and infected lung, respectively. We conclude that fosfomycin achieves antimicrobially effective concentrations in infected lung tissue.