Hospital acquired infection and antibiotic resistance Flashcards Preview

YEAR 1: MCD - Microbiology > Hospital acquired infection and antibiotic resistance > Flashcards

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

What is the breakpoint?

A

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
Q

Name some major antibiotic resistant Gram-negative bacterial pathogens.

A
Pseudomonas aeruginosa
Klebsiella
Salmonella
Acinetobacter baumanii
Neisseria gonorrheae
3
Q

Name some major antibiotic resistant Gram-positive bacterial pathogens.

A
Staphylococcus aureus (MRSA)
Streptococcus pneumoniae
Clostridium dificile
Enterococcus spp.
Mycobacterium tuberculosis
4
Q

Name 7 types of antibiotic.

A
Beta-lactams
Aminoglycosides
Chloramphenicol
Tetracycline
Quinolones
Sulphonamides
Macrolides
5
Q

How do beta-lactams work? Give some examples.

A

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
Q

How do quinolones work?

A

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

7
Q

How do macrolides work? Give an example.

A

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

8
Q

How do aminoglycosides work? Give some examples.

A

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

9
Q

How do sulphonamides work?

A

Inhibits the folate pathway

10
Q

How does tetracycline work?

A

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

11
Q

How does chloramphenicol work?

A

Inhibits the peptidyl transfer step

Binds to the 50S subunit

12
Q

What are the four main mechanisms of antibiotic resistance?

A

Altered target site
Inactivation of antibiotic
Altered metabolism
Decreased drug accumulation