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Phase 2a medicine > Microbiology > Flashcards

Flashcards in Microbiology Deck (36)
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1
Q

What test differentiates between gram positive cocci?

A

Catalase test

2
Q

What is catalase positive?

A

Staphylococcus

3
Q

What is catalase negative?

A

Streptococcus

4
Q

How are staphylococcus arranged?

A

Clusters

5
Q

How are streptococcus arranged?

A

Chains

6
Q

What is the coagulase test?

A

An enzyme produced by staph aureus coverts soluble fibrinogen into insoluble fibrin

7
Q

What is positive for the coagulase test?

A

S.aureus

8
Q

What is negative for the coagulase test?

A

Staph epidermidis and saprophyticus

9
Q

What is alpha haemolytic strep?

A

Greening on blood agar

10
Q

What is beta haemolytic strep?

A

Clear on blood agar

11
Q

What is gamma haemolytic strep?

A

No lysis on blood agar

12
Q

Name beta haemolytic strep?

A

S.pyogenes

13
Q

What test differentiates between alpha haemolytic strep?

A

Optochin test

14
Q

Sensitive to optochin disc?

A

S.pneumonia

15
Q

Resistant to optochin disc?

A

Viridans strep

16
Q

Gamma haem strep?

A

Enterococcus

17
Q

Gram positive rods?

A

Corneybacteria, mycobacteria, listeria, bacillus, nocardia

18
Q

Which gram negative bacilli appear pink on maccconkey?

A

E.coli and klebsiella

19
Q

What type of bacteria are pink on MacConkey?

A

Lactose fermenting

20
Q

What type of bacteria are white on MacConkey?

A

Non-lactose fermenting

21
Q

Non lactose fermenting bacteria?

A

Shigella, salmonella, pseudomonas, proteus

22
Q

Which test differentiates between the non-lactose fermenting bacteria?

A

Oxidase test

23
Q

What is oxidase positive?

A

Pseudomonas

24
Q

What is oxidase negative?

A

Shigella, salmonella and proteus

25
Q

Gram negative cocci?

A

Neisseria, moraxella

26
Q

Antibiotics to treat shigella?

A

Quinolones, Azithromycin

27
Q

Antibiotics to treat salmonella?

A

Amoxicillin, quinolones, macrolides

28
Q

Antibiotics to treat neisseria?

A

Cephalosporins

29
Q

Antibiotics to treat MRSA?

A

Gentamicin, Vancomycin

30
Q

Treatment for bacterial meningitis?

A

Cephalosporins: IV cefotaxime/ IV ceftriaxone

31
Q

What type of antibiotics should you use for gram positive and why?

A

Usually use penicillins as they have thick walls and they inhibit cell wall synthesis/

32
Q

What antibiotic would you give to someone with a penicillin allergy?

A

A macrolide

33
Q

Give 2 examples of a macrolide?

A

Clarithromycin and erythromycin

34
Q

Which antibiotic should you not give to pregnant women?

A

Trimethoprim as it inhibits folic acid synthesis

35
Q

What should you treat UTI’s with?

A

Nitrofurantoin and trimethoprim

36
Q

What stain is used for Mycoplasm tuberculosis?

A

Ziehl-Neelsen stain (stains red)