Chemotherapy Flashcards
Why do antibiotics select for resistant strains?
If resistance is present, the antibiotics will always win GIVEN that it is the correct antibiotics for that resistant strain
What is the role that chemotherapy has on microorganism load, and what does this allow for the body to do?
Chemotherapy lowers the microorganism load, allowing the body’s defense system to rid of the foreign organism
Which four medications or classes of medications exhibit renal toxicity?
- Cephalosporins
- Vancomycin
- Aminoglycosides
- Sulfa drugs
Which four medications or classes of medications exhibit hepatic toxicity?
- Tetracyclines
- Erythromycin
- Clindamycin
- Sulfa drugs
Which two medications or classes of medications exhibit ototoxicity?
- Aminoglycosides
- Vancomycin
Which two medications or classes of medications exhibit hemopoietic toxicity?
- Chloramphenicol
- Sulfa drugs
Which two medications or classes of medications exhibit hemolytic anemia as an adverse side effect?
- Sulfa drugs
- Nitrofurantoin
Which three medications or classes of medications exhibit photosensitivity as an adverse side effect?
- Tetracyclines
- Fluoroquinolones
- Sulfa drugs
What are the three primary mechanisms by which antibiotics select for drug resistance (MOR)?
- Inactivate drug itself
- Modify drug target
- Efflux pumps
What are three methods by which antibiotic resistance is acquired (not natural)? Which one requires cell-to-cell contact?
- Transduction
- Transformation
- Conjugation: requires cell-to-cell contact
Describe transduction.
Bacteriophages
Describe transformation.
Incorporation of free DNA
Describe conjugation.
Transfer of genes via sex pili
When should empirical therapy be started?
BEFORE the pathogen is known
Which antibiotic susceptibility involves cell death?
Bactericidal
Which antibiotic susceptibility involves inhibition of growth?
Bacteriostatic
Why would you use bactericidal over bacteriostatic?
Bacteriostatic are NOT effective in immunocompromised
- Must use bactericidal (does not rely on immune system)
If you have an immunocompromised patient and the only non-resistant antibiotic option is bacteriostatic, what does this mean?
They will need to be on life-long bacteriostatic abx therapy
Is maintenance of constant blood levels more important with bacteriostatic or bactericidal agents? Why?
Maintenance of constant blood levels is more important with bacteriostatic because this helps to prevent the development of resistance
What are two antibiotic examples of concentration dependent killing, and what type of agents are these?
- Aminoglycosides (bactericidal)
- Fluoroquinolones (bactericidal)
What is concentration dependent killing?
Rate and extent of killing is dependent on drug concentration
What are two antibiotic examples of time dependent killing, and what type of agents are these?
- Vancomycin (bactericidal)
- Beta-lactams (bactericidal)
What is time dependent killing?
Rate and extent of killing is dependent on time of exposure to antibiotic
- Killing is NOT increased with increased concentrations
What type of agent primarily effects protein synthesis or THF synthesis?
Bacteriostatic
