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Postantibiotic leukocyte enhancement of meropenem against gram-positive and gram-negative strains

A Novelli1, S Fallani, M I Cassetta

  • 1Dipartimento di Farmacologia Preclinica e Clinica, Università degli Studi di Firenze, Florence, Italy. novelli@server1.pharm.unifi.it

Antimicrobial Agents and Chemotherapy
|October 19, 2000
PubMed

Insights

Meropenem demonstrated a stronger postantibiotic effect on leukocyte enhancement (PALE) than imipenem against common bacteria. This suggests meropenem may be more effective in boosting immune cell activity after antibiotic exposure.

Area of Science:

  • Microbiology
  • Immunology
  • Pharmacology

Background:

  • The postantibiotic effect (PAE) describes the suppression of bacterial growth after antibiotic exposure.
  • Leukocyte enhancement is a critical component of the host immune response to bacterial infections.

Purpose of the Study:

  • To compare the postantibiotic leukocyte enhancement (PALE) of meropenem and imipenem in vitro.
  • To evaluate the impact of carbapenem pre-exposure on polymorphonuclear cell (PMN) phagocytic activity.

Main Methods:

  • In vitro evaluation of meropenem and imipenem.
  • Exposure of 24 Gram-positive and Gram-negative bacterial strains to carbapenems at four times the minimum inhibitory concentration (MIC) for 2 hours.
  • Assessment of subsequent polymorphonuclear cell phagocytic killing.

Main Results:

  • Pre-exposure to carbapenems generally enhanced polymorphonuclear cell phagocytic killing.
  • Meropenem exhibited a significantly greater PALE compared to imipenem across tested bacterial strains.

Conclusions:

  • Meropenem shows superior efficacy in enhancing leukocyte function post-exposure compared to imipenem.
  • These findings highlight potential differences in the immunomodulatory effects of carbapenems, with implications for infection treatment strategies.

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