Microbiology and Infectious Diseases Flashcards Preview

Clinical Pathology > Microbiology and Infectious Diseases > Flashcards

Flashcards in Microbiology and Infectious Diseases Deck (51):
1

Inhibit bacterial growth by inhibiting protein synthesis

Bacteristatic

2

Kill bacteria

Bactericidal

3

Minimum Inhibitory Concentration

Minimum concentration of antibiotic at which visible growth is inhibited

4

Give a syndergistic example of 2 types of antibiotics used to treat streptococcal endocarditis

Aminoglycoside and beta lactam

5

Which types of antibiotics target the bacterial cell wall?

Beta lactams and glycopeptides

6

What is the name of the major constituent of bacterial cell walls and name the 2 glucose derivatives that it is made up of

Peptidoglycan
N-acetyl muramic acid (NAM)
N-acetyl glycosamine (NAG)

7

Describe the beta lactam ring

C-C-C-N in a ring structure. Structural analogue of D-alanyl D-alanine

8

How do beta lactams work?

Interfere with the function of the 'penicillin binding proteins' (transpeptidase enzymes) involved in the peptidoglycan cross linking

9

Name 4 types of beta lactams

Penicillins, cephalosporins, carbapenems,monobactams

10

Amoxicillin is an example of what type of antibiotic?

Penicillin- beta lactam

11

cefuroxime is an example of what type of antibiotic?

cephalosporin-beta lactam

12

meropenem is an example of what type of antibiotic?

carbapenem

13

azteronam is an example of what type of antibiotic?

monobactam

14

Give an example of a glycopeptide

Vancomycin

15

How do glycopeptides work?

Bind directly to terminal D-alanyl-D-alanine on NAM to prevent binding of transpeptidases and thus peptidoglycan cross linking

16

Glycopeptides work on what sort of bacteria?

Gram +ve- unable to penetrate outer membrane on gram -ves

17

Name the different antibiotics that act as protein synthesis inhibitors

Aminoglycosides
Macrolides, Lincosamides, streptogramins (MLS)
Tetracyclines
Oxazolidinones
(others e.g. mupirocin, fusidic acid)

18

Name an example of an aminoglycoside

Gentamycin

19

How do aminoglycosides work?

Bind to 30s ribosomal subunit

20

Name an example of a macrolide

Erythromycin

21

How do MLS antibiotics work?

Bind to 50S ribosomal subunit

22

Name an example of a tetracycline

doxytetracycline

23

How do tetracyclines work?

Bind to 30S ribosomal subunit, and interfere with binding of tRNA to rRNA

24

Name an example of an oxazolidinone

Linezolid

25

How do oxazolidinones work?

Bind to 50S ribosomal subunit and inhibits assembly of initiation complex.

26

Name the types of DNA Synthesis inhibitors

Trimethoprim and Sulfonamides
Quinolones and Fluoroquinolones

27

How do trimethoprim and sulfonamides work?

Inhibit folate synthesis- folic acid is a purine synthesis precursor.

28

What is the target enzyme in DNA synthesis that trimethoprim targets?

Dihdydrofolate reductase

29

What is the target enzyme in DNA synthesis that sulfonamides target?

Dihydropteroate synthetase

30

Give an example of a trimethoprim/sulfonamide antibiotic

Co-trimoxazole (trimethoprim/sulfomethoxazole)

31

How do quinolones and fluoroquinolones act?

Inhibit enzymes involved in remodelling of DNA during DNA replication

32

Give an example of a quinolone/fluoroquinolone

Ciprofloxacin

33

What categories of antibiotics act as RNA synthesis inhibitors?

Rifampicin

34

How does rifampicin work?

RNA polymerase inhibitor- prevents synthesis of RNA

35

What adverse effects are common with aminoglycosides?

reversible renal impairment and ototoxicity -toxic to ear

36

What adverse effects commonly occur with beta lactams?

Allergic reactions and rashes

37

What adverse effects commonly occur with linezolid

Bone marrow depression

38

Safe to use which beta lactams in patients with non-severe penicillin allergy?

Cephalosporins and carbapenems

39

Safe to use which beta lactam in patients with severe penicillin allergy?

Aztrenam (unicycle)

40

What is the name of the hypervirulent strain of C.Diff?

027

41

C.Diff may be precipitated by any antibiotic, but which 4 most commonly?

Co-amoxiclal cephalosporin, ciproflaxin, clindamycin

42

Clindamycin belongs to what group of antibiotics?

Lincosamide

43

3 strategies of antibiotic use- in order of specificity

Empiric, targeted, susceptibility guided

44

What antibiotic is used to treat staph A

Flucloxacillin

45

What antibiotic is used to treat steptococcus pyogenes

Benzylpenicillin

46

What class of antibiotic is used to treat gram -ve bacilli

Cephalosporins

47

What type of antibiotic is used to treat anaerobes?

Metronidazole

48

What antibiotic is used to treat gram +ves?

Vancomycin

49

What antibiotic is used as a last option to treat multi-resistant gram negatives?

Colistin

50

What antibiotics are used to treat CSF infections?

beta lactams

51

What antibiotics are used to treat urine infections?

Trimethoprim and beta lactams