Hospital acquired infection and antibiotic resistance Flashcards Preview

MCD - Microbiology- Laz > Hospital acquired infection and antibiotic resistance > Flashcards

Flashcards in Hospital acquired infection and antibiotic resistance Deck (12):
1

What is the breakpoint?

The concentration of antibiotic that can be achieved in a clinical setting
If the bacteria can divide at a concentration at or higher than the breakpoint, it is deemed resistant

2

Name some major antibiotic resistant Gram-negative bacterial pathogens.

Pseudomonas aeruginosa
Klebsiella
Salmonella
Acinetobacter baumanii
Neisseria gonorrheae

3

Name some major antibiotic resistant Gram-positive bacterial pathogens.

Staphylococcus aureus (MRSA)
Streptococcus pneumoniae
Clostridium dificile
Enterococcus spp.
Mycobacterium tuberculosis

4

Name 7 types of antibiotic.

Beta-lactams
Aminoglycosides
Chloramphenicol
Tetracycline
Quinolones
Sulphonamides
Macrolides

5

How do beta-lactams work? Give some examples.

Penicillin and Methicillin
They have a beta-lactam ring that is a similar shape to a precursor of peptidoglycan in the bacterial cell wall and hence interferes with the synthesis of the cell wall

6

How do quinolones work?

Quinolones inhibit the functioning of DNA gyrase (Gram-negative) and topoisomerase (Gram-positive) hence hampering the unravelling of DNA during replication

7

How do macrolides work? Give an example.

Only Gram-positive infections
Targets the 50S ribosomal subunit and prevents the peptidyl transfer step
Erythromycin

8

How do aminoglycosides work? Give some examples.

Aminoglycosides affect RNA proofreading leading to misfolded proteins
Some of these proteins get incorporated into the membrane and cause leakage
Gentamycin and Streptomycin

9

How do sulphonamides work?

Inhibits the folate pathway

10

How does tetracycline work?

Prevents charged amino-acyl tRNAs from binding to the mRNA/ribosome complex

11

How does chloramphenicol work?

Inhibits the peptidyl transfer step
Binds to the 50S subunit

12

What are the four main mechanisms of antibiotic resistance?

Altered target site
Inactivation of antibiotic
Altered metabolism
Decreased drug accumulation