[In vitro activity of meropenem and seven other beta-lactam antibiotics against K.pneumoniae and enterobacteriaceae producing beta-lactamases with extended spectrum]

Pathol Biol (Paris). 1994 May;42(5):365-8.
[Article in French]

Abstract

Meropenem is a broad antibacterial spectrum carbapenem with a good activity on betalactam resistant Gram-negative bacilli. 120 non repetitive strains isolated from clinical samples from 1989 to 1992 were selected: 60 K. pneumoniae, 7 E. coli, 2 E. aerogenes and 1 S. marcescens with extended spectrum betalactamases (23 CTX-1, 18 SHV-2, 5 SHV-3, 16 SHV-4, 4 SHV-5, 3 CTX-1 + SHV-4, 1 CAZ-1), 10 K. pneumoniae with broad spectrum TEM-1 enzyme, and 40 K. pneumoniae with only SHV-1 chromosomal betalactamase. Determination of Minimal inhibitory concentrations (MIC) was done by agar dilution method for meropenem and 7 other betalactams (amoxicillin + clavulanic acid 2 mg/l, piperacillin + tazobactam 4 mg/l, cefoxitin, cefotetan, cefotaxime, ceftazidime, imipenem). All antibiotics except amoxicillin + clavulanic acid are active against strains with constitutive penicillinase. For strains with TEM-1 penicillinase, cephamycins, third generation cephalosporins and carbapenems are active. For strains with different extended spectrum betalactamases only cephamycins and carbapenems are efficious. There is no difference according to the period of isolation: 1989-90 or 1991-92. Meropenem has the best in vitro activity (MIC50 = 0.03 mg/l) for all strains independently of the nature of betalactamase.

MeSH terms

  • Anti-Bacterial Agents / pharmacology*
  • Carbapenems / pharmacology
  • Dose-Response Relationship, Drug
  • Enterobacteriaceae / drug effects*
  • Enterobacteriaceae / enzymology
  • Escherichia coli / drug effects
  • In Vitro Techniques
  • Klebsiella pneumoniae / drug effects*
  • Klebsiella pneumoniae / enzymology
  • Meropenem
  • Thienamycins / pharmacology*
  • beta-Lactamases / metabolism*

Substances

  • Anti-Bacterial Agents
  • Carbapenems
  • Thienamycins
  • beta-Lactamases
  • Meropenem