Part 11-1: Treatment of Infection

Question 1

Anti-infectious agents

Answer 1

Antibacterials
Antivirals
Antifungals
Others

Question 2

Anti-infectious agents common goal

Answer 2

Selective toxicity to invading organism

Question 3

Bacteria

Answer 3

Single cell microorganisms
Rigid cell membrane
Different ribosomes
Different nucleic acid metabolism

Question 4

Antibacterial drug categories

Answer 4

1. Inhibit cell wall synthesis and function
2. Inhibit protein synthesis
3. Inhibit DNA and RNA synthesis and function

Question 5

Inhibition of cell wall synthesis & function

Answer 5

Bacterial membrane contains peptidoglycans

Certain agents inhibit synthesis or create hole in lipid bilayer

Penicillins (inhibit peptidoglycan)

Cephalosporins (Inhibit peptidoglycan)

Polymixin B inhibition (create hole in phospholipids)

Question 6

Inhibition of protein synthesis

Answer 6

Bacterial ribosome slightly different

Agents bind to ribosome, inhibit protein synthesis

Tetracyclines, erythromycin, aminoglycosides

Question 7

Inhibition of DNA/RNA function

Answer 7

Nucleic acid metabolism different

Some drugs decrease DNA synthesis by inhibiting folic acid production

Others directly inhibit bacterial DNA/RNA synthesis/function

Question 8

DNA/RNA inhibition common examples

Answer 8

Sulfanomides (Wound care)
Fluoroquinolones (Anthrax)
Trimethroprim (Early synthesis)
Metronidazole (Directly to DNA)
Rifampin (Inhibit transcription)

Question 9

Bactericidal vs bacteriostatic

Answer 9

• cidal kills

- static slows reproductive function

Question 10

Antibacterial Spectrum

Answer 10

Broad effective against many types

Narrow effective against specific type

Question 11

Antibacterial Resistance

Answer 11

Strains develop natural defense against drugs via spontaneous mutation

Question 12

Common resistant strains

Answer 12

VRSA
MRSA
VRE
PRSP

Question 13

Common resistance mechanisms

Answer 13

Develop drug-destroying enzymes
Alter or mask binding site
Change enzymes
Decrease penetration
Develop drug efflux pumps

Question 14

Bacterial resistance prevention

Answer 14

Antibacterial stewardship (avoid overuse, use narrow spectrum whenever possible)

Question 15

Bacterial resistance treatment

Answer 15

Provide 2nd drug to overcome resistance

Question 16

Antibacterials adverse effects

Answer 16

Hypersensitivity; allergic rxns
UV sensitivity
Tendon Damage

Question 17

Fluoroquinolone tendon damage

Answer 17

Often large, wt bearing tendons
Risk increased in:
-older pt
-Renal Failure
-Taking glucocorticoids
-Hx of damage

Question 18

Tendon damage cause

Answer 18

Unclear (Oxidative damage?)
Onset can be rapid
Most cases within 1st month

Question 19

Virus characteristics

Answer 19

Viral DNA or RNA “core”

Surrounded by protein shell (Capsid)

Question 20

Viral Replication

Answer 20

Virus adsorbs onto host cell

Virus penetrates into host cell, releases genetic material

Viral DNA or RNA takes over host cell, uses cell to make new viruses

Symptoms related to loss of host function, other direct viral effects

Question 21

Viral Replication steps

Answer 21

1. Adsorption
2. Penetration & uncoating
3. Biosynthesis
4. Maturation & release

Question 22

Antiviral drugs

Answer 22

Fairly specific
Typically inhibit viral enzymes
Usually virustatic

Question 23

Interferons

Answer 23

Small proteins, produced endogenously
-Control cell division/differentiation
-Control immune responses
Possible antiviral role

Question 24

Specific Interferons

Answer 24

Interferon alfa n-3 (warts)
Interferon alfacon-1 (Hep-C)
Interferon alfa 2b: (warts, hep B, hep C)

Question 25

Antiviral Vaccines

Answer 25

Typically made from “modified” virus

Administered prior to exposure to virus

Stimulate immune system to produce virus-specific antibodies