UK31214, a new aminoglycoside and derivative of kanamycin B

The in vitro activity of UK31214, a kanamycin B derivative, was studied against 250 recent isolates and compared with other aminoglycosides. Against the Enterobacteriaceae (with the exception of Proteus mirabilis and Providencia stuartii) UK31214 and amikacin had similar degrees of activity (mode minimum inhibitory concentration [MIC], 1 microgram/ml). Proteus mirabilis and P. stuartii strains were four- to eight-fold more susceptible to amikacin than to UK31214. Pseudomonas aeruginosa strains were equally susceptible to both amikacin and UK31214 (mode MIC, 4 microgram/ml), but tobramycin was the most active antimicrobial agent tested (mode MIC, 0.25 microgram/ml). The gentamicin-resistant strains of P. aeruginosa were equally susceptible to UK31214 and amikacin. Strains of Staphylococcus aureus were more susceptible to gentamicin or tobramycin than to UK31214 or amikacin (mode MIC, 0.5 microgram/ml). A synergistic interaction between UK31214 and carbenicillin was demonstrated.