Clinical Study of the Use of the New Aminoglycoside Tobramycin for Therapy of Infections Due to Gram-Negative Bacteria

Tobramycin, a new aminoglycoside antimicrobial, was evaluated as therapy for infections due to gram-negative bacilli in 15 seriously ill patients with underlying diseases. Three of 10 patients with gram-negative bacteremias also had urinary tract infections. Two patients had respiratory tract infections, one had cellulitis, one had a urinary tract infection, and another had septic phlebitis. Twelve patients were cured of their infections. Eosinophilia was observed in one patient and another developed superinfection with Staphylococcus aureus after 6 days of tobramycin therapy. There were five isolates of Escherichia coli, five of Klebsiella sp., two of Pseudomonas sp., and one each of Enterobacter agglomerans, Serratia marcescens, and Enterobacter cloacae. The average serum concentration of tobramycin 2 h after a parenteral dose of 1.0 to 1.5 mg/kg was 5.1 mug/ml; higher concentrations of tobramycin were present in urine. Tobramycin proved to be an effective antimicrobial in these patients.