netilmicin and micronomicin

Antimicrobial activity of dactimicin, a pseudo-disaccharide aminoglycoside antibiotic, was compared with those of dibekacin, netilmicin, sisomicin and micronomicin using clinical isolates of four Gram-positive and sixteen Gram-negative bacteria. Dactimicin was more active than the reference amino-glycosides against Serratia marcescens, especially gentamicin-resistant Serratia sp., Proteus vulgaris, P. rettgeri and Klebsiella oxytoca, but less active against Pseudomonas aeruginosa and P. mirabilis. Dactimicin was equally active as the references excepting netilmicin against Gram-positive bacteria and some Gram-negative bacteria including Escherichia coli, K. pneumoniae, Morganella morganii, Haemophilus influenzae, Citrobacter freundii, Enterobacter aerogens, E. cloacae, Acinetobacter calcoaceticus and Campylobacter jejunii. Dactimicin was active against resistant strains possessing various aminoglycoside-modifying enzymes including AAC(3)-1, by which dactimicin was acetylated.

Topics: Aminoglycosides; Anti-Bacterial Agents; Bacteria; Bacterial Infections; Dibekacin; Drug Resistance, Microbial; Gentamicins; Microbial Sensitivity Tests; Netilmicin; Sisomicin

A high-performance liquid chromatographic method for monitoring serum levels of the aminoglycoside antibiotics sisomicin, netilmicin, astromicin, and micronomicin, using an amino acid analysis system is described. The procedure involves sample preparation with a CM-Sephadex column, and quantitation using internal standards chosen from each of the other aminoglycosides. The aminoglycosides were separated by reversed-phase ion-pair chromatography on Zorbax C8 and ODS columns, and detected by the post-column derivatization technique. The calibration curves of serum concentration for sisomicin, netilmicin, astromicin, and micronomicin were linear over the ranges 0.32-22.8 micrograms/ml, 0.17-11.6 micrograms/ml, 0.1-6.3 micrograms/ml, and 1.0-30 micrograms/ml, respectively. The coefficients of variation were 2.5, 2.8, 3.1 and 1.9%, at the serum concentrations of 1.3, 1.45, 1.58 and 2.5 micrograms/ml, respectively (n = 6). Determination by the internal standard method using another aminoglycoside gives accurate and reproducible results. This method is applicable also to other aminoglycoside antibiotics.

Topics: Aminoglycosides; Anti-Bacterial Agents; Chromatography, High Pressure Liquid; Gentamicins; Humans; Netilmicin; Sisomicin