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Antimicrobials and BRD

Mike Apley1

  • 1Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA. mapley@ksu.edu

Animal Health Research Reviews
|December 17, 2009
PubMed

Insights

Pharmacodynamics and antimicrobial susceptibility testing offer limited precision for individual animal therapy due to complex biological factors. However, these methods remain valuable for assessing antimicrobial effectiveness within animal populations.

Area of Science:

  • Veterinary Pharmacology
  • Microbiology
  • Pharmacodynamics

Background:

  • Pharmacodynamics (PD) presents challenges in predicting therapeutic outcomes due to factors like drug binding, concentration variations (tissue vs. plasma), degradation, microbial differences, and infection site environment.
  • Antimicrobial susceptibility testing (AST) also shows limitations when applied to individual animals, hindering precise treatment guidance.

Purpose of the Study:

  • To evaluate the limitations of current pharmacodynamic principles in guiding veterinary antimicrobial therapy.
  • To assess the precision and applicability of antimicrobial susceptibility testing in individual animal treatment versus population-based assessments.

Main Methods:

  • Review of existing literature on pharmacodynamics and antimicrobial susceptibility testing in veterinary medicine.
  • Analysis of factors influencing drug efficacy and microbial response in animal models and clinical settings.

Main Results:

  • Pharmacodynamics is significantly complicated by unbound drug states, variable drug concentrations, drug metabolism, pathogen diversity, and localized infection environments, limiting precise therapeutic predictions.
  • Antimicrobial susceptibility testing demonstrates imprecision for individual animal treatment decisions.

Conclusions:

  • Current pharmacodynamic models and antimicrobial susceptibility testing require further refinement for precise individual animal therapy guidance.
  • Antimicrobial susceptibility testing remains a valuable tool for epidemiological surveillance and understanding antimicrobial resistance patterns in animal populations.

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