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SUMMARY
Pharmacodynamic concepts should be applied to optimize
antibiotic dosing regimens, particularly in the face of
some multidrug resistant bacterial infections. Although
the pharmacodynamics of most antibiotic classes used in
the hospital setting are well described, guidance on how
to select regimens and implement them into an antimi-
crobial stewardship program in one’s institution are more
limited. The role of the antibiotic MIC is paramount in
understanding which regimens might benefit from imple-
mentation as a protocol or use in individual patients. This
review article outlines the pharmacodynamics of amino-
glycosides, beta-lactams, fluoroquinolones, tigecycline,
vancomycin, and polymyxins with the goal of providing a
basis for strategy to select an optimized antibiotic regimen
in your hospital setting.
Key words: Gram-negative bacteria, resistance,
pharmacokinetics, MIC, prolonged infusion.
INTRODUCTION
Antibiotic resistant infections are a worldwide public health
problem. As a result of emerging resistance in both Gram-
positive and Gram-negative bacteria, pathogens that
remain susceptible to most currently available antibiotics
OPTIMIZING ANTIMICROBIAL
PHARMACODYNAMICS: A GUIDE FOR
YOUR STEWARDSHIP PROGRAM
JOSEPH L. KUTI, PHARMD (1)
(1) Center for Anti-Infective Research and Development, Hartford Hospital, Hartford, CT USA.
Correspondence: Center for Anti-Infective Research and Development, Hartford Hospital, Connecticut, USA.
Email:
Item received: 25-07-2016
Article approved for publication: 26-08-2016
are diminishing and few antibiotics are in development to
address these multidrug resistant (MDR) bacteria (1). Among
Gram-positive bacteria, Staphylococcus aureus that are
resistant to beta-lactams [i.e., methicillin-resistant S. aureus
(MRSA)] can be found in as many as 50-60% of isolates
(2). We are at the point clinically, whereby if S. aureus is a
suspected cause of the infection, empiric therapy with an
anti-MRSA antibiotic has become essential. On the Gram-
negative side, Pseudomonas aeruginosa continues to be
a problematic pathogen due to its high prevalence in the
hospital setting; however, the emergence of carbapenem
resistant enterobacteriaceae (CRE) and carbapenem resistant
Acinetobacter baumannii (CRAB) has rightly stolen headlines
and are considered Urgent and Serious threats, respectively,
by the Centers for Diseases Control (2,3). The lack of new
antibiotics is particularly problematic in countries outside
of the United States and European Union. Many of these
countries have regulatory requirements that significantly
delay the approval of new drugs, or in extreme cases, never
make them available. As a result, the countries that often
have the direst levels of MDR organisms seldom have the
newest, most potent antibiotics in their armamentarium.
In addition to encouraging the continued development
of new antibiotics, efforts must be made within the
hospital setting to limit the emergence and spread of
[REV. MED. CLIN. CONDES - 2016; 27(5) 615-624]