Antimicrobials

Question 1

What are antimicrobials

Answer 1

Drugs that kill or inhibit the growth of micro-organisms

Question 2

What are examples of antimicrobials

Answer 2

Antibiotics 
Antiviral drugs 
Anti fungal drugs 
Anti protozoa 
Anti parasitc drugs

Question 3

What are sites to where of groups of antibiotics can work

Answer 3

Bacterial cell wall and membrane
Nucleic acid synthesis
Protein synthesis

Question 4

What types of antibiotics target the bacterial cell wall and and membrane

Answer 4

Penicillins 
Cephalosporins 
Carbapenems 
Monobactams 
Glycopeptides
Polymxins

Question 5

Which type of antibiotics target nucleic acid synthesis

Answer 5

Folate antagonists
Dna gyrase: Quinolones
Rna polymerase: rifmycins

Question 6

Which type of antibiotics target protein synthesis

Answer 6

50s subunit:

• macrolides
• lincomycins
• oxozolidiones
• chroamphenicol

30s subunit:

• tetracylines
• aminoglycosides

Question 7

Which type of bacteria lack a membrane

Answer 7

Gram positive bacteria

Question 8

Which type of bacteria have a membrane

Answer 8

Gram negative

Question 9

How do antibiotics inhibit the cell wall synthesis i.e target the cell wall and membrane

Answer 9

By creating beta lactam rings

Question 10

Which antibitoics are beta lactam antibiotics

Answer 10

Penicillin
Chephalosporins
Carpanenems
Monobactams

Question 11

What does glycopeptide target

Answer 11

target gram positive organism

Question 12

What are examples of folate synthesis inhibitors

Answer 12

Sulfonamides

Trimethoprim

Question 13

What do sulfonamide target in folate synthesis

Answer 13

PABA (structural analogues) so they compete

Question 14

What are trimethoprim

Answer 14

Strucutrual analogues of folate so they compete with it

Question 15

Is trimethoprim and sulfonamide safe in pregnancy

Answer 15

No because babies require folate

Question 16

How can we measure the effectiveness of antibiotics

Answer 16

In vitro

In vivo

Question 17

What is the minimum inhibitory concentration

Answer 17

The minimum in vitro concentration which an antibiotic can inhibit growth

Question 18

What is the minum bactericidal concentration

Answer 18

The minimum in vitro concentration which an antibiotic can kill bacteria

Question 19

How can we measure in vitro antibiotic effectiveness

Answer 19

By looking at:
Minimum inhibitory concentration
Minimum bactericidal concentration

Question 20

How can we detect resistance mutation

Answer 20

By PCR

Question 21

What do we need to consider in invivo effectiveness

Answer 21

Pharmacokinetics
Pharmacodynamics
Drug interaction 
Foreign material
Source control
Host immune response

Question 22

What are the factors in pharmokinetics

Answer 22

Absorption
Distribution
Metabolism
Excretion

(ADME)

Question 23

What is distribution

Answer 23

The volume of distribution that relates to the concentration of drug in blood relative to the dose given

Question 24

Where does metabolism of drugs occur

Answer 24

in the liver

Question 25

Where are the sites of excretion

Answer 25

Renal excretion | Biliary or gut

Question 26

What is a small volume of distribution due to

Answer 26

Durg being plasma bound

Question 27

What is a large volume of distribution due to

Answer 27

Fat soluble drug

Question 28

What is antimicrobial resistance

Answer 28

The ability of the microbe to resist the effects of medication that once could successfully treat the microbe

Question 29

What are the mechanism of antimicrobial resistance

Answer 29

1. Production of enzymes 2. Changes to target sites or metabolic pathways 3. Efflux pumps

Question 30

What are the 3 main pathogens restant

Answer 30

MRSA VRE ESBL

Question 31

What are examples of production of enzymes for antimicrobial resistance

Answer 31

Beta lactam enzymes can be produced which hydrolyse beta lactam molcule so the antibiotics cant work

Question 32

How can we stop production of beta lactam enzyme

Answer 32

Give decoy substrates that bind to the enzyme

Question 33

What are the ways in having changes to target sites of metbolic pathways

Answer 33

``` Mutation to stop binding of beta lactams Methylation of rRNA Mutations in the gene for DNA gyrase Mutation in porin channles Use of exogenous thymidine or thymidine for DNA synthesis ```

Question 34

How do efflux pumps cause antimicrobial resistance

Answer 34

Efflux pumps pump out the antibiotic from the bacterial cell via porins

Question 35

What are the 4 main drug immune mediated reactions

Answer 35

Type 1 Type 2 Type 3 Type 4

Question 36

What is type 1 immune mediated reactions

Answer 36

Ige mediated response

Question 37

What is type 2 immune mediated reactions

Answer 37

Cytotoxic production resulting in drug induced haemolysis

Question 38

What are type 3 immune mediated reactions

Answer 38

Immune complexes resultsin in serum sickness like (fever, rash, arthralgia) reactions after several days

Question 39

What is type 4 immune mediated reaction

Answer 39

Delayed hypersensitivity

Question 40

What does type 1 immune mediated response cause

Answer 40

Urticaria, angioedema, or anaphalyaxis reaction

Question 41

Which antibiotics are safe in pregnancy

Answer 41

``` Penicillins Cephalosporins Clindamycin Glycopeptides Metronidazole ```