2. What is meant by antimicrobial resistance? Susceptibility?
3. Why are pure cultures used for antimicrobial susceptibility testing?
4. Would it be acceptable to use a mixed culture for this test? Why?
5. List three factors that can influence the accuracy of the test.
6. When performing a broth dilution test, why is it necessary to include a
growth control tube? A sterility control tube?
7. How can the
minimum bactericidal concentration of an antimicrobial agent
be determined from an MIC assay?
8. Could an organism that is susceptible to an antimicrobial agent in
laboratory testing fail to respond to it when that drug is used to treat the
9. Are antibacterial agents useful in viral infections? Explain.
10. Why is it better to use the word
susceptible rather than the word sensitive
in describing an organism’s response to a drug? When speaking of the
patient, what does the term
drug sensitivity mean?
11. Describe a mechanism of bacterial resistance to antimicrobial agents.
12. If the laboratory isolates
S. aureus from five patients on the same day, is it
necessary to test the antimicrobial susceptibility of each isolate? Why?