Abstract
Cefepime (CFPM) is a new aminothiazole-methoxyimino cephalosporin which bears a quaternized 1-methylpyrrolidine attached to the 3-position methylene. The usefulness of CFPM in the treatment of bacterial respiratory tract infection was evaluated. The antimicrobial activity (50% minimum inhibitory concentration: MIC50) of CFPM against major respiratory pathogenic organisms was 0.05μg/ml against Streptococcus pneumoniae, 0.2μg/ml against Haemophilus influenzae, 0.39μg/ml against Branhamella catarrhalis, 6.25μg/ml against Staphylococcus aureus, and 6.25μg/m; against Pseudomonas aeruginosa. The concentrations in serum, sputum and bronchial secretion were determined by bioassay using Morganella morganii IFO 3848 as a test organism in patients with respiratory infection receiving i.v. drip infusion of CFPM (1g b.i.d.). The maximal concentrations of CFPM in serum (n=2) were 74.3 and 85.2 μg/ml. Serum half-lives (n=3) ranged from 2.3 2.9 h. The sputum levels (n=2) ranged from 0.25-1.48 μg/ml and the bronchial secretion level (n=1) was 4.3 genii. The ratio of maximal sputum level to maximal serum level as a percentage in one case was 1.74%. Nineteen cases of respiratory infection were subjected to clinical evaluation with CFPM, and received i.v. drip infusion of CFPM (1g b.i.d.). Bacteriological eradication rate was 100% for all S. pneumoniae (8), H. influenzae (3), B. catarrhalis (1), Klebsiella sp.(2) and Escherichia coli (1), isolates. Two strains of P. aeruginosa, one strain each of S. aureus and Xanthomonas maltophilia were not eradicated. The overall eradication rate and clinical efficacy for CFPM were 78.9%(15/19 strains) and 84.2%(16/19 cases), respectively. No adverse drug side effects or abnormalities of laboratory findings were seen in these cases. In summary, CFPM is a most effective cephalosporin antibiotic in the treatment of bacterial respiratory infection.
