beta-Lactamase susceptibility and comparative activity of Sch 34343 and other beta-lactams for non-fermenters, Neisseria spp. and beta-lactamase-positive Enterobacteriaceae.
By means of a micro-dilution technique (10(5) cfu/cup) 30 strains of Pseudomonas spp. were found resistant to Sch 34343. The susceptibility of Acinetobacter spp. (20 strains) was greatest for imipenem, followed by Sch 34343 (MIC approximately 0.7 mg/l), ceftazidime and ceftriaxone. Ten Moraxella strains were very susceptible to Sch 34343, imipenem and ceftazidime. For 35 strains of Neisseria gonorrhoeae (ten beta-lactamase-positive) and ten strains of N. meningitidis we noted no resistance to Sch 34343 (MIC 0.015-0.06 mg/l), or to any of the other drugs tested. Sixty-two strains of Enterobacteriaceae producing various beta-lactamases were tested for their sensitivity to Sch 34343 and seven other beta-lactams. To an even greater extent than imipenem and Sch 34343, latamoxef and ceftazidime proved very active against all these strains. A PSE-4-producing Escherichia coli strain was resistant to Sch 34343. The inoculum effect (10(6) vs 10(4) cfu/ml) on Sch 34343 activity was usually small (1-4). Tests for the beta-lactamase susceptibility of Sch 34343 showed that only one PSE-3, one PSE-4 and one chromosomal beta-lactamase from a strain of Enterobacter cloacae were slightly active.
D000150:Acinetobacter / Q000187:drug effects / Q000201:enzymology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003470:Culture Media; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000201:enzymology; D007769:Lactams; D008826:Microbial Sensitivity Tests; D009016:Moraxella / Q000187:drug effects / Q000201:enzymology; D009343:Neisseria / Q000187:drug effects*; D011550:Pseudomonas aeruginosa / Q000187:drug effects; D001618:beta-Lactamases / Q000378:metabolism*; D047090:beta-Lactams
D000900:Anti-Bacterial Agents; D003470:Culture Media; D007769:Lactams; D047090:beta-Lactams; C044617:Sch 34343; D001618:beta-Lactamases