[Dibekacin--a novel aminoglycoside antibioticl. Antimicrobial activity and parallel resistance in vitro]

Dibekacin (Orbicin) is a new aminoglycoside antibiotic which chemically differs from tobramycin only by lack of an OH-group. The activity of dibekacin against E. coli, Klebsiella, Enterobacter, Serratia, Proteus indol-negative and indol-positive and Pseudomonas aeruginosa was compared with that of gentamicin, sisomicin, tobramycin and amikacin by tube dilution procedure. Dibekacin showed a high activity against P. aeruginosa including gentamicin-resistant strains. The development of resistance and cross-resistance in vitro in E. coli, Klebsiella, Proteus and P. aeruginosa to the five aminoglycosides was investigated. The experimentally produced resistance under increasing aminoglycoside concentrations was developing by multiple-step mutation. The frequency of cross-resistance is of great importance for the first choice of an aminoglycoside antibiotic in the hospitals. These in vitro studies have yielded that dibekacin and gentamicin are well suited for the first choice of an aminoglycoside in P. aeruginosa infection.