[Clinical studies on fosfomycin sodium following intravenous administration (tissue concentration and clinical efficacy)].

Fosfomycin (FOM) is a synthetic antibiotic having a unique structural formula and bactericidal mechanism and a broad spectrum of antimicrobial activity against various bacterial species. It has higher activity in vivo than in vitro. As therapy, FOM-Na in a daily dose of 4 g (2 g X 2) was given by intravenous drip infusion for 5 to 10 days to 6 cases with infectious diseases (2 cases of acute cholecystitis, 3 cases of acute localized peritonitis due to phlegmonous appendicitis and 1 case of acute diffuse peritonitis due to perforative appendicitis). The clinical response was rated as "excellent" in 1 case, "good" in 4 cases, "fair" in 1 case and "poor" in none. No adverse effects were observed in any of the patients. Six clinical isolates were obtained, and these consisted of 4 strains of Escherichia coli and 1 strain each of Klebsiella pneumoniae, and Bacteroides fragilis. The MICs of FOM were from 6.25 to 12.5 micrograms/ml for E. coli, 50 micrograms/ml for K. pneumoniae, and 100 micrograms/ml for B. fragilis. FOM-Na was administered to the 6 cases intravenously in a dose of 2 g before surgery, and tissue specimens and body fluid samples were taken during the operation. The FOM concentration was determined by bioassay with a Proteus sp. (MB 838) as the test organism. The mean FOM concentration in bile from the common bile duct was 61.85 +/- 17.13 micrograms/ml (n = 5) at 95 to 108 minutes after FOM-Na intravenous bolus injection. The mean FOM concentration in the gall bladder bile was 80.06 +/- 92.36 micrograms/ml, while that in the gall bladder wall was 146.65 +/- 39.10 micrograms/g. The mean FOM concentration in purulent ascites was 58.20 +/- 13.29 micrograms/ml, 36.22 +/- 14.63 micrograms/g in the appendix wall and 12.64 +/- 11.34 micrograms/ml in pus in the appendix. The FOM concentrations in the infected tissues and body fluids thus exceeded the MICs of FOM for the pathogenic bacteria. Therefore, FOM-Na appears to be a very useful drug when used for chemotherapy of infections encountered in the surgical field.