[Susceptibilities of clinical isolates to aminoglycoside antibiotics. Susceptibility of clinical isolates from patients with complex and refractory infections].

Four hundred strains (13 species, 8 genera) were obtained from patients with complicated and intractable infections. The antibiotic sensitivities of these isolates were determined in relation to aminoglycoside (AGs) (GM, DKB, AMK, HBK), beta-lactam (SBPC, PIPC, CMZ), and FOM. 1. The frequency of clinical isolates that were resistant to GM and DKB in this study was high level in the case of S. aureus, Enterobacter spp., S. marcescens, Proteus spp. (indole positive) and P. aeruginosa. And some of them were also resistant to AMK and HBK. However HBK had potent antibacterial activity to S. aureus. The inactivating enzyme contributing to AGs resistance was AAC for almost Gram-negative bacillis and APH + AAC for S. aureus. But AGs was not permeable only to P. maltophilia. 2. Almost similar resistant patterns were seen to SBPC and PIPC. However, the frequency of resistant strains of S. aureus to SBPC was less than one of PIPC, while that of Citrobacter spp. to PIPC was less than SBPC. Among of other bacteria, P. aeruginosa and Proteus spp. (indole positive) had moderate sensitivity to SBPC and PIPC. 3. CMZ had poor antibacterial activity to Enterobacter spp. and S. marcescens and no activity to P. aeruginosa. It had moderate activity to Citrobacter spp. and potent activity to S. aureus, E. coli, K. pneumoniae and Proteus spp. (indole positive). 4. FOM had antibacterial activity to all the bacteria tested. Almost FOM-sensitive bacteria had moderate MICs (6.25-25 micrograms/ml).