Disposition of phosphomycin in patients with pleural effusion.
The pharmacokinetics of phosphomycin were studied in seven patients with pleural effusion of varied etiologies. All patients received a single intravenous bolus of 30 mg of antibiotic per kg. Phosphomycin levels in plasma and pleural fluid were determined simultaneously. Antibiotic levels in plasma followed a two-compartment open kinetic model. In the pleural fluid, maximum concentrations of phosphomycin, 42.63 +/- 16.03 micrograms/ml (mean +/- standard deviation), were reached at 3.69 +/- 1.08 h after administration of the antibiotic. The disappearance constant of the antibiotic from the pleural fluid was significantly smaller (0.16 +/- 0.06 h-1) than the elimination constant determined from the levels of drug in plasma (0.73 +/- 0.26 h-1). Phosphomycin persisted in antibacterial concentrations in the pleural fluid for a considerable period of time. The low accessibility of phosphomycin observed in one of the patients in the study, with a maximum concentration value of 2.16 micrograms of phosphomycin per ml of pleural fluid, could be due to the existence of pachypleuritis in that patient; this was later confirmed in clinical and histological studies done after the research described here.
D000368:Aged; D000900:Anti-Bacterial Agents / Q000378:metabolism*; D001681:Biological Assay; D001826:Body Fluids / Q000378:metabolism; D005260:Female; D005578:Fosfomycin / Q000378:metabolism* / Q000627:therapeutic use; D006801:Humans; D007700:Kinetics; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D010996:Pleural Effusion / Q000188:drug therapy / Q000378:metabolism*
D000900:Anti-Bacterial Agents; D005578:Fosfomycin