Lecture 12: Antibiotics Part 1 Flashcards
Antibacterials are produced by organisms to do what?
To eliminate bacterial competitors and predators
How do selectively toxic antibiotics work?
- Target cell structure, enzymes, or pathways that are unique to bacteria
- Don’t harm human cells
How do broad spectrum antibiotics work? In what situation would they be given?
- Inhibit/kill many species/classes of bacteria
- Can kill Gram-positive and Gram-negative bacteria
- Given first when infection is suspected but ID is not available
How do narrow spectrum antibiotics work?
- Inhibit/kill a few species/classes of bacteria
- Often correlated with cell wall type
- Typically kills Gram-positive OR Gram-negative bacteria
Why are Gram-negative bacteria typically more resistant to antibiotics?
Because of their restrictive double membrane
Antibiotics can be bacteriostatic and/or bactericidal. What does bacteriostatic vs. bactericidal mean?
- Bacteriostatic: inhibits bacterial cell division and can be reversed when the antibiotic is removed
- Requires the immune system to clear the bacteria - Bactericidal: kills the bacteria and will not grow even in the absence of the antibiotic
Define minimum inhibitory concentration (MIC).
Lowest concentration of an antimicrobial that will inhibit the detectible growth of a microorganism after overnight incubation
_____ will determine if a particular bacterium is resistant, intermediate, or susceptible to an antibiotic.
MIC breakpoints
Where can you find guidelines for breakpoints and antibiotics?
Clinical and Laboratory Standards Institute (CLSI) documents
What parts of bacteria could antibiotics target?
Give an overview of the history of antibiotics.
How are antibiotics prescribed (i.e. what things to consider)?
- Not all drugs have breakpoints and not all drugs work for all sites
- What antibiotic to report and when to report are determined by CLSI and hospital/clinical lab
- Hospitals don’t carry all antibiotics
- Patient allergies and tolerance to the antibiotic
What is antibiotic stewardship?
The effort to measure and improve how antibiotics are prescribed by clinicians and used by patients
Antibiotics are responsible for what fraction of emergency department visits for adverse drug effects?
1 out of 5
Antibiotics are the most common cause of emergency department visits for what in children under 18?
Adverse drug events
What are 5 reasons why antibiotics can be toxic?
