[Fundamental and clinical studies on cefuzonam in the field of pediatrics].

Fundamental and clinical studies on cefuzonam (L-105, CZON), a newly semisynthesized cephem antibiotic, were carried out in the field of pediatrics and the following results were obtained. Antibacterial activities of CZON against clinically isolated strains of Staphylococcus aureus, S. epidermidis, Streptococcus pneumoniae, S. pyogenes, Escherichia coli, Klebsiella pneumoniae, Haemophilus parainfluenzae and H. influenzae were compared with those of cefmenoxime (CMX), latamoxef (LMOX), cefoperazone (CPZ), cefmetazole (CMZ), cefotiam (CTM) and cefazolin (CEZ). CZON was nearly as active as CEZ against S. aureus and S. epidermidis and superior to other antibiotics against other Gram-positive cocci. Against Gram-negative rods, CZON was as active as CMX and superior to other 5 antibiotics compared. Serum concentrations and urinary excretion rates after intravenous bolus injection of CZON at doses of 10 mg/kg, 20 mg/kg and 40 mg/kg for 5 minutes in 1, 5 and 4 cases, respectively, were determined. Mean serum concentrations of CZON at these dose levels were 11.0, 43.8 and 111.5 micrograms/ml at 15 minutes, 2.4, 10.3 and 30.3 micrograms/ml at 1 hour and 0.17, 0.72 and 1.28 micrograms/ml at 4 hours, with serum half-lives of 1.79, 0.88 and 1.19 hours, respectively. Mean cumulative urinary excretion rates within 6 hours after administration were 47.9, 56.3 and 40.3%, respectively. Thirty-four pediatric patients with various bacterial infections (tonsillitis 2, acute bronchitis 1, pneumonia 14, pyothorax 1, sepsis 1, suppurative lymphadenitis 1, UTI 13 and enteritis 1) were treated with CZON at a daily dose of 40-94 mg/kg t.i.d. or q.i.d.. The overall clinical efficacy rate was 94.1%. No adverse reactions were observed except 2 cases with mild diarrhea. Abnormal laboratory findings were also mild; slight elevation of GOT and GPT in 2, eosinophilia in 1 and thrombocytosis in 1. These results clearly indicate the usefulness of CZON in the treatment of bacterial infections in children.