Antimicrobials

Question 1

Antibacterial soap that target cell wall

Answer 1

Beta lactams

Glycopeptides

Question 2

Mechanism of action of beta lactams

Answer 2

Bind to penicillin binding protein that forms cross links holding the cell wall together, preventing cell wall synthesis.

Question 3

Glycopeptides mechanism

Answer 3

Bind to end of cell wall polypeptide chain preventing penicillin binding protein from adding cross links

Question 4

Examples of antimicrobials that interfere with protein synthesis

Answer 4

Amino glycosides
Tetracycline
Macrolides

Question 5

Example of antimicrobials that interfere with nucleic acid synthesis

Answer 5

Quinolones

Question 6

3 mechanisms of drug resistance

Answer 6

Drug inactivating enzyme
Altered target
Altered uptake

Question 7

Give examples of beta lactams

Answer 7

Penicillin
amoxicillin
Cephalosporins
Carbapenems

Question 8

Describe coamoxiclav and tazocin

Answer 8

Beta lactams + beta lactams even inhibitors

Strep/staph/anaerobes/gram negs

Question 9

Give 4antibacterials with anaerobes activity

Answer 9

Coamoxiclav
Tazocin
Carbapenem e.g. Meropenem
Metronidazole

Question 10

What is used for meningitis

Answer 10

Centriaxone, cephalosporin
Gram neg activity
Good activity in CSF crosses blood brain barrier

Question 11

What beta lactams used in penicillin allergy

Answer 11

Meropenem
Broadest spectrum
Carbapenem

Question 12

Activity of glycopeprides

Answer 12

Only Gram positive

Question 13

Example of glycopeptide

Answer 13

Vancomycin

Question 14

Treatment of C. difficile

Answer 14

Metronidazole in mild mod
Vancomycin in severe
Not absorbed orally

Question 15

Treatment of UTI

Answer 15

Tetracyclines
Doxycycline
Trimethoprim (folic acid inhibition)

Question 16

Treatment of legionella

Answer 16

Tetracycline

Question 17

Example of amino glycoside

Answer 17

Gentamicin

Question 18

Macrolide example

Answer 18

Erythromycin

Question 19

Treatment of H pylori

Answer 19

Triple therapy
Azithromycin
Cephalosporins 
Omeprazole
Ranitidine

Question 20

Action of quinolone mechanism

Answer 20

Inhibit DNA topiosomerase and DNA gyrate to prevent supercooling of DNA so there is reduced space for further DNA production

Question 21

Quinolones action

Answer 21

Gram negative

Question 22

Example quinolone

Answer 22

Ciprofloxacin

Question 23

Treatment of influenza

Answer 23

Oseltamivir

Question 24

Treatment of varicella zoster

Answer 24

Aciclovir

Question 25

Treatment of candida

Answer 25

Fluconazole

Question 26

Treatment of malaria

Answer 26

``` Plasmodium falciparum Quinine artemisinin Vivax, ovale, malariae Chloroquine Primaquine (ROS g6pdd screen) ```

Question 27

Targets for antimicrobial action

Answer 27

Cell wall synthesis Protein synthesis Nucleic acid synthesis Membrane function

Question 28

Treatment of Atypical Pneumonia

Answer 28

Don't have cell wall so beta lactams don't work Macrolides - Clarythromycin Tetracyclines - doxycycline

Question 29

Treatment of community acquired pneumonia

Answer 29

Moderate - co-amoxiclav or erythromycin (macrolide) | Severe - Both

Question 30

Treatment of hospital acquired pneumonia

Answer 30

More likely to be gram negative | Co-amoxiclav

Question 31

Treatment of pnemonia

Answer 31

``` Oral/IV fluid Antipyretic Analgesic Antibiotic Oxygen ```

Question 32

Treatment of pneumocystis pneumonia

Answer 32

Pneumocystis jiroveci | Cotrimoxazole

Question 33

How do surface infection microorganisms evade antibiotics?

Answer 33

Formation of biofilm through quorum sensing. Secrete slime layer in which substances can diffuse and protects the bacteria colony. Dense extracellular matrix and outer layer of cells protect the interior community. Allows for spread of antibiotic resistance through quorum sensing. Lateral gene transfer is greatly increased.

Question 34

Describe biofilm formation.

Answer 34

Adhesion using pili and fimbriae. Growth and colonisation. Quorum sensing to secrete extracellular matrix slime. Nutrients diffuse into matrix. Dispersion - biofilm is established and spread occurs.

Question 35

What is quorum sensing?

Answer 35

``` Coordination of bacteria in colony based on population density through a series of stimuli and responses. Used to coordinate Biofilm formation Spore formation Resistance Increased virulence ```

Question 36

Anaerobic activity

Answer 36

Metronidazole, co-amoxiclav, meropenem, tazocin