Susceptibility of group B streptococci to 16 beta-lactam antibiotics, including new penicillin and cephalosporin derivatives

Antimicrob Agents Chemother. 1982 Nov;22(5):897-900. doi: 10.1128/AAC.22.5.897.

Abstract

The susceptibility of 100 group B streptococci to 16 beta-lactam antibiotics was tested by agar dilution. Penicillin G and N-formimidoyl thienamycin were the most active agents tested, both having a 90% minimal inhibitory concentration (MIC90) of 0.06 microgram/ml. Ceftriaxone, cefotaxime, cefamandole, and SCH 29482 were almost as active, all having an MIC90 of 0.12 microgram/ml, and ampicillin, cephalothin, and mezlocillin all had an MIC90 of 0.25 microgram/ml. The MIC90 for piperacillin, cefoperazone, and ceftazidime was 0.5 microgram/ml. Least active were carbenicillin, ticarcillin, cefoxitin, and moxalactam, with MIC90s of 1, 2, 4, and 8 micrograms/ml, respectively. No penicillin-tolerant strains were detected.

MeSH terms

  • Anti-Bacterial Agents / cerebrospinal fluid
  • Anti-Bacterial Agents / pharmacology*
  • Anti-Bacterial Agents / therapeutic use
  • Cephalosporins / pharmacology*
  • Humans
  • Infant, Newborn
  • Infant, Newborn, Diseases / drug therapy
  • Meningitis / drug therapy
  • Microbial Sensitivity Tests
  • Penicillins / pharmacology*
  • Streptococcus agalactiae / drug effects*

Substances

  • Anti-Bacterial Agents
  • Cephalosporins
  • Penicillins