Intro to Antibiotics and Resistance

Question 1

Identify the classes of antimicrobials

Answer 1

Antibacterial
Antiviral
Antifungal
Antiprotozoal

Question 2

Describe the classification of antibacterials

Answer 2

• Bactericidal (Kill) OR bacteriostatic (Stop replication)
• Broad OR narrow spectrum
• According to their target site (mechanisms of action)
• According to chemical structure

Question 3

What 7 questions do you ask when choosing which antibiotic to use

Answer 3

• Is it active against target
• does it reach infection site
• IV or Oral
• what is the half life (decides dosing frequency)
• does it interact with other drugs
• are there toxicity issues
• does it require monitoring

Question 4

What are the 4 mechanisms of action of antibacterial agents

Answer 4

Cell wall synthesis
Protein synthesis
Cell membrane function
Nuclei acid synthesis

Question 5

What are 3 types of antibacterial resistance

What are 3 mechanisms

Answer 5

Intrinsic
Acquired
Adaptive

Enzymatic modification of antibiotics
Enzymatic alteration of antibiotic targets
Mutations of bacterial target sites

Question 6

How do antifungals work
How do antivirals work

Give an example of a drug that combats both Protozoa and bacteria

Answer 6

F: inhibit cell-membrane synthesis
V: inhibit DNA polymerase

Metronidazole

Question 7

Which antibacterial classes affect cell wall synthesis

Answer 7

Beta- Lactams (Penicillins, Cephalosporins)

Glycopeptides

Question 8

Which antibacterial classes affect protein synthesis

Answer 8

Tetracyclines and doxycyclines
Aminoglycolides
Macrolides

Question 9

Which antibacterial classes affect cell membrane function

Answer 9

Polymixins

Question 10

Which antibacterial classes affect nucleic acid synthesis

Answer 10

Quinolones
Trimethoprim
Rifampicin

Question 11

Which drug is used to treat cellulitis

Which is used to treat a Urinary Tract Infection

Answer 11

Cellulitis: Flucloxacillin
UTI: Nitrofurantoin

Question 12

What are 3 mechanisms of antibiotic resistance

Answer 12

Natural resistance
Genetic mutation
Acquired mutation (From other bacteria)

Question 13

Name 3 consequences of antibacterial resistance

Answer 13

Treatment failure
Prophylaxis failure
Economic costs

Question 14

Describe the 3 definitions of antimicrobial resistance

Answer 14

MDR (Multi drug resistant);
- Non susceptibility to at least one agent in 3 or more antimicrobial categories

XDR (Extensively drug resistant);
- Non susceptibility to at least one agent in all but 2 or less categories

PDR (pan drug resistant);
- Non susceptibility to all agents in all antimicrobial categories