In vitro activity of imipenem-relebactam and ceftolozane-tazobactam against resistant gram-negative bacilli

Suzannah M. Schmidt-Malan, Avisya J. Mishra, Ammara Mushtaq, Cassandra L. Brinkman, Robin Patel

Research output: Contribution to journalArticle

11 Scopus citations

Abstract

Understanding which antimicrobial agents are likely to be active against Gram-negative bacilli can guide selection of antimicrobials for empirical therapy as mechanistic rapid diagnostics are adopted. In this study, we determined the MICs of a novel -lactam–-lactamase inhibitor combination, imipenem-relebactam, along with ceftolozane-tazobactam, imipenem, ertapenem, meropenem, ceftriaxone, and cefepime, against 282 drug-resistant isolates of Gram-negative bacilli. For isolates harboring blaKPC (n 110), the addition of relebactam to imipenem lowered the MIC50/MIC90 from 16/ 128 g/ml for imipenem alone to 0.25/1 g/ml. For isolates harboring blaCTX-M (n 48), the MIC50/MIC90 of ceftolozane-tazobactam were 0.5/16 g/ml (83% susceptible). For isolates harboring blaCMY-2 (n 17), the MIC50/MIC90 of ceftolozane-tazobactam were 4/8 g/ml (47% susceptible). Imipenem-relebactam was active against most KPC-producing (but not NDM- or IMP-producing) Enterobacteriaceae and is an encouraging addition to the present antibiotic repertoire.

Original languageEnglish (US)
Article numbere00533-18
Pages (from-to)1DUMMY
JournalAntimicrobial Agents and Chemotherapy
Volume62
Issue number8
DOIs
StatePublished - Aug 1 2018

Keywords

  • Antimicrobial resistance
  • Gram-negative bacilli

ASJC Scopus subject areas

  • Pharmacology
  • Pharmacology (medical)
  • Infectious Diseases

Fingerprint Dive into the research topics of 'In vitro activity of imipenem-relebactam and ceftolozane-tazobactam against resistant gram-negative bacilli'. Together they form a unique fingerprint.

  • Cite this