Abstract
Laboratory and clinical investigations were performed on tobramycin (abbreviated as TOB) and the results were obtained as folows;
1) Sensitivity of clinically isolated strains to TOB was tested by agar plate dilution method and compared with that of gentamicin (GM) and 3', 4'-dideoxykanamycin B (DKB).
The minimum inhibitory concentrations of TOB against 50 strains of Staphylococci, 50 strains of E. coli and 28 strains of Proteus were 0.39 to 6.25 μg/ml, 1.56 to 12.5 μg/ml and 1.56 to 50 μg/ml respectively. Forty seven out of 50 strains of Klebsiella pneumoniae and 68 out of 70 strains of Pseudomonas aeruginosa were inhibited at the range of 0.39 to 6.25 μg/ml of TOB. The antibacterial activity of TOB was found supperior to that of GM or DKB against Pseudomonas aeruginosa.
2) Serum concentrations of 80 mg of TOB with single intramuscular injection reached to peak after 1 hour of administration, and the levels ranged from 5.2 to 9.2 μg/ml with mean concentration of 7.1 μ/ml. The growth of Pseudomonas aeruginosa was inhibited within 4 or 8 fold dilution of serum obtained after 1 hour of TOB administration.
3) Three cases out of 4 patients with respiratory tract infections treated with TOB showed effective clinical result. No side effect was observed in all patients.
