Rachel's Notes Questions

Question 1

Penicillins act on gram negative or gram positive organisms?

Answer 1

Both gram positive and gram negative.

Question 2

Penicillins are safe in pregnancy. True/False?

Answer 2

True.

Question 3

How does penicillin work?

Answer 3

Inhibits cell wall synthesis with autolysins.

Autolysins degrade the cell wall and affect the osmotic pressure.

Question 4

Are cephalosporins safe in pregnancy?

Answer 4

Yes

Question 5

Give 2 examples of glycopeptides

Answer 5

Vancomycin and teicoplanin.

Question 6

How are glycopeptides given?

Answer 6

Intravenously, are not absorbed when given orally but can be given orally where they act on the gut lumen (this is ONLY for C Diff)

Question 7

Glycopeptides are used to treat gram__ organism?

Answer 7

Gram positive

Question 8

How are macrolides excreted?

Answer 8

Via the liver & biliary tree.

Question 9

What feature of macrolides allow them to pass through the cell membrane so easily?

Answer 9

They are lipophilic.

Question 10

Are macrolides safe in pregnancy?

Answer 10

No, with the exception of Erythromycin

Question 11

Give an example of an aminoglycoside and its route of administration.

Answer 11

Gentamicin (IV)

Question 12

Aminogycosides are used against gram___ organisms?

Answer 12

Gram negative

Question 13

What do broad spectrum antibiotics do?

Answer 13

Work on gram negative and gram positive organisms.

Question 14

What makes something produce endotoxin?

Answer 14

The presence of lipopolysaccharide.

Question 15

What does C diff produce when there is no competition due to the eradication of the gut’s natural flora?

Answer 15

Produce exotoxin leading to severe diarrhoea.

Question 16

What is Clindamycin used for?

Answer 16

A 2nd line treatment to treat staph/strep cocci in penicillin allergic patients.

Question 17

What is Chloramphenicol used to treat?

Answer 17

It is a topical treatment used for eye infections.

Question 18

Are tetracyclines bactericidal or bacteriostatic?

Answer 18

Both bactericidal and bacteriostatic.

Question 19

What does doxycycline do?

Answer 19

Treat atypical bacteria without a proper cell wall and some chest & skin infections in penicillin allergic patients.

Question 20

How does co-trimoxazole work?

Answer 20

Inhibit bacterial folic acid synthesis by binding to enzymes needed to form folic acid.

Question 21

Are fluoroquinolones bactericidal or bacteriostatic? In addition, what makes them special?

Answer 21

Bactericidal

They are broad spectrum antibiotics

Question 22

Give 2 examples of fluoroquinolones and 3 things they are used to treat.

Answer 22

Pseudomonas infection
Ciprofloxacin (IV or oral) is used to treat complicated UTIs
IV levofloxacin is used to treat severe CAP in penicillin allergic patients.

Question 23

What is the rare type of allergy to glycopeptides such as vancomycin called?

Answer 23

Red man syndrome.

Question 24

What does a TRUE hypersensitivity reaction involve? And what medications must these patients avoid?

Answer 24

Low BP, itchy rash, difficulty breathing, swelling at injection site.
Avoid penicillins and cephalosporins

Question 25

Which 2 medications should be avoided in the first trimester of pregancy?

Answer 25

Metranidazole and trimethoprim

Question 26

Which 3 medications should NOT be given to pregnant women at all?

Answer 26

Gentamycin, tetracycline and fluroquinolones.

Question 27

Give the 2 ways in which bacteria acquire resistance.

Answer 27

Genetic mutations - misreading DNA | Transfer of DNA that codes for antibiotic resistance from 1 bacterium to another.

Question 28

Name and describe the 3 mechanisms by which genes for antibiotic resistance are transferred to other bacteria.

Answer 28

Transformation (bacteria dies and releases free DNA, another bacterium incorporates this free DNA into their structure, acquiring resistance) Conjugation (2 bacteria are in close proximity, form a bridge called a "pilus", the plasmid replicates and one copy is transferred over) Transduction (virus ("phage") invades bacterium. The bacterium's resistant DNA is incorporated into the virus' DNA. When the bacterium dies, the virus is released and can transfer this DNA onto other bacterial cells).

Question 29

Name the 3 mechanisms of resistance.

Answer 29

Altered binding site Destruction or activation of antibiotic Increased efflux via efflux pumps channels meaning antibiotics are exported out of the bacterial cells.