[Comparative study of the antibacterial activity of a number of new antibiotics and their combinations in relation to Pseudomonas aeruginosa].

Tobramycin and sisomycin proved to have the highest antibacterial activity against 156 clinical strains of Ps. aeruginosa and were 4--8 times more effective than monomycin, kanamycin, neomycin and to a lesser extent gentamicin. The combination of mecillinam and sisomycin had a synergistic effect with respect to 26 out of 50 strains of Ps. aeruginosa and the combination of mecillinam and tobramycin had a synergistic effect on 18 strains. An antagonistic effect was observed with the use of the above combinations in 3 cases. The effect of the combinations depended on sensitivity of Ps. aeruginosa cultures to the aminoglycoside antibiotic included into the compositions.