Antibiotics Flashcards
(68 cards)
1
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Staphylococcus
A
Gram positive
Coccus
Aerobic
2
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Streptococcus
A
Gram positive
Coccus
Aerobic
3
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Enterococcus
A
Gram positive
Coccus
Aerobic
4
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Peptostreptococcus
A
Gram positive
Coccus
Anaerobic
5
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Propionibacterium
A
Gram positive
Coccus
Anaerobic
6
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Listeria
A
Gram positive
Bacillus
Aerobic
7
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Clostridium
A
Gram positive
Bacilllus
Anaerobic
8
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Bacillus
A
Gram positive
Bacillus
Aerobic
9
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Corynebacterium
A
Gram positive
Bacillus
Aerobic
10
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Neisseria
A
Gram negative
Coccus
Aerobic
11
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Coliforms
A
Gram negative
Bacillus
Aerobic
12
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Haemophilus
A
Gram negative
Coccobacillus
Aerobic
13
Q
For the following bacteria, describe
- Gram stain
- Shape
- Air requirement
Bordetella
A
Gram negative
Coccobacillus
Aerobic
14
Q
What antibiotic classes are inhibitors of cell wall synthesis?
A
Beta-lactams
Glycopeptides
15
Q
What antibiotic classes are inhibitors of the 30S ribosomal subunit?
A
Aminoglycosides
Tetracyclines
16
Q
What antibiotic classes are inhibitors of the 50S ribosomal subunit?
A
Lincosamides
Macrolides
Fusidic acid
Linezolid
17
Q
What antibiotic classes are inhibitors of folic acid synthesis?
A
Trimethoprim
Sulphonamides
18
Q
What antibiotic classes are inhibitors of DNA gyrase?
A
Fluoroquinolones
19
Q
What antibiotic classes are inhibitors of RNA polymerase?
A
Rifamycins
20
Q
What antibiotic classes are disrupts of DNA strands?
A
Nitroimidazoles
21
Q
What antibiotic classes are inhibitors of cell membrane function?
A
Colistin
Daptomycin
22
Q
What antibiotic classes are bactericidal?
A
Penicillins Cephalosporins Carbapenams Glycopeptides Fluoroquinolones Rifamycins Aminoglycosides Metronidazole
23
Q
What antibiotic classes are bacteriostatic?
A
Macrolides Lincosamides Tetracyclines Trimethoprim Sulphonamides
24
Q
What sort of infection does discoloured sputum suggest?
A
Bacterial, rather than viral
25
What are the typical causes of community acquired pneumonia?
```
Streptococcus pneumoniae
Haemophilus influenzae type b
Staphylococcus aureus
Streptococcus pyogenes
Moraxella catarrhalis
Anaerobes
Aerobic and facultative Gram negative rods
```
26
What are the atypical causes of community acquired pneumonia?
```
Mycoplasma pneumoniae
Legionella
Chlamydophila pneumoniae
C psittaci
Chlamydia trachomatis
Coxiella burnetii
```
27
What are examples of narrow spectrum penicillins?
```
Penicillin G
Penicillin V
Procaine penicillin
- Procaine slows absorption rate
Benzathine pencillin
```
28
What are examples of moderate spectrum penicillins?
Amoxycillin
| Ampicillin
29
What are examples of broad spectrum penicillins?
Piperacillin
| Ticarcillin
30
Against which bacteria do broad spectrum penicillins have?
Pseudomonas aeruginosa
31
When would you use broad spectrum penicillins?
If complicating factors present
32
What do beta-lactamase inhibitors do?
Inhibit most beta-lactamases produced by bacteria
33
What are examples of beta-lactamase inhibitors?
Clavulanic acid
| Tazobactam
34
What are examples of beta-lactam/beta-lactamase inhibitor combinations?
Amoxycillin-clavulanate
Piperacillin-tazobactam
Ticarcillin-clavulanate
35
If a patient develops a rash within 24 hours of commencing penicillin, which antibiotics would you use?
Cephalosporins
36
What should you keep in mind when using cephalosporins as an alternative antibiotic in people with penicillin allergies?
Some cross-reactivity between true penicillin allergy and some cephalosporins
Rare
37
What are examples of first generation cephalosporins?
```
Oral
- Cephalexin
IV
- Cephazolin
- Cephalothin
```
38
What is the spectrum of first generation cephalosporins?
Gram positives
| Some common Gram negatives; eg: E coli
39
What are examples of second generation cephalosporins?
Oral
- Cefuroxime
- Cefaclor
40
What is the spectrum of second generation cephalosporins?
Same as 1st generation
| Slightly enhanced activity against Gram negatives; eg: H influenzae
41
What are examples of third generation cephalosporins?
IV
- Ceftriaxone
- Cefotaxime
42
What is the spectrum of third generation cephalosporins?
Enhanced Gram negative activity
| Less Gram positive activity, especially against S aureus
43
What are examples of fourth generation cephalosporins?
IV
- Ceftazidime
- Cefepime
44
What is the spectrum of ceftazidime?
Gram negatives, including Pseudomonas aeruginosa
| Poor against Gram positives, especially S aureus
45
What is the spectrum of cefepime?
Gram negatives, including P aeruginosa
| Some Gram positive activity, including against Streptococcus and S aureus
46
When are fourth generation cephalosporins used a lot?
Febrile neutropaenia
47
What are examples of fifth generation cephalosporins?
IV
- Ceftaroline
- Ceftolozane
48
What is the spectrum of ceftaroline?
Gram positives, including MRSA
| Gram negatives except Pseudomonas
49
What is the spectrum of ceftolazane?
Pseudomonas
| Gram negative activity
50
Which antibiotic classes have intracellular activity?
Tetracyclines
Macrolides
Fluoroquinolones
51
What differential diagnoses should you consider when considering community acquired pneumonia?
```
Upper respiratory tract infections
Acute exacerbation of chronic bronchitis
Cardiac failure
Pulmonary embolus
Endocarditis
Liver abscess
```
52
What antibiotic classes have Gram negative activity?
```
Minimal/some
- Moderate spectrum penicillins
- 1st and 2nd generation cephalosporins
Penicillin/beta-lactamase inhibitor combinations
3rd and 4th generation cephalosporins
Gentamicin
Fluoroquinolones
```
53
What antibiotic classes have anaerobic activity?
```
Penicillin
Metronidazole
Beta-lactam/beta-lactamase inhibitor combinations
Carbapenems
Clindamycin
Moxifloxacin
```
54
Why is vancomycin given orally in the treatment of Clostridium difficile?
Oral vancomycin not absorbed very well > stays in gut - where you need it
Also undergoes 1st pass hepatic metabolism, so not much enters systemically
55
What cause true rigors?
Influenza
| Bacteria
56
Is there a clinical benefit in treating asymptomatic bacteriuria?
No
Exceptions
- Pregnancy
- Patients undergoing urology procedures
57
Why is asymptomatic bacteriuria usually not treated?
Exposes patient to complications
| Promotes antibiotic resistance
58
Signs of splinter haemorrhages and Janeway lesions suggest what?
Infective endocarditis
59
What is MRSA resistant to?
All beta-lactams
60
Describe penicillin G
Beta-lactam
Also called benzylpenicillin
Narrow spectrum
Mainly active against Gram positive bacteria
Inactivated by beta-lactamases
IV administration
Treatment of choice for susceptible infections; eg: pneumococcal pneumonia
61
Describe flucloxacillin
```
Beta-lactamase
Food impairs absorption
Dosed at 6-hourly intervals
Usually well tolerated
Rarely associated with
- Cholestatic jaundice, especially in older patients on prolonged therapy
IV/oral
```
62
Describe ceftriaxone
3rd generation cephalosporin
Broad spectrum
- Including majority of community-associated enteric Gram negative rods
- Less active against Staphylococcus
Inactive against MRSA
Anti-staphylococcal activity dose dependent
Not useful against enterococci
Effective in meningitis
Risk-benefit ratio in neonates
Shouldn't be mixed with Ca-containing IV solutions
63
Describe gentamicin
Aminoglycoside
Broad spectrum activity against Gram negative bacteria
- Including P aeruginosa
64
Describe ciprofloxacin
```
Quinolone
Reserved for
- Infections resistant to other drugs
- Oral therapy when alternative antibiotics not available
Broad spectrum activity against Gram negative bacteria
- Haemophilus influenzae
- Enteric Gram negative rods
- P aeruginosa
- Gram negative cocci
- Some Gram positive cocci
- Legionella
- Several mycobacteria
Not active against anaerobes
Poor activity against streptococci
```
65
Describe vancomycin
Glycopeptide
Broad spectrum activity against Gram positive bacteria
Primary indication: treatment for
- MRSA
- Methicillin-resistant coagulase negative staphylococci; eg: S epidermidis
- Enterococcus faecium
Used in people with penicillin hypersensitivity
Oral vancomycin reserved for severe cases/those not responding to metronidazole when treating C difficile
- To avoid development of VRE
66
Describe metronidazole
```
Nitroimidazole
Broad spectrum activity against
- Gram negative anaerobic bacteria
- Gram positive anaerobic bacteria
- Helicobacter pylori
- Protozoa
Can cause disulfiram-like reaction when used with alcohol
- Abstain during treatment for up to 72 hours after completing course
```
67
Describe doxycycline
Tetracycline
Broad spectrum
- Gram positive and negative bacteria
- Chlamydia
- Rickettsia
- Mycoplasma
- Spirochetes
- Some non-TB mycobacteria
- Some protozoa; eg: malaria-causing Plasmodium
Can cause oesophagitis
Should be taken with food and full glass of water
Can cause photosensitivity
Tooth discolouration and enamel dysplasia in children
- Reactions minimal if single short courses used
68
Describe acyclovir
```
Nucleic acid analogue
Primarily used for treatment of
- HSV
- Chickenpox (VZV)
- Shingles (VZV)
Other uses
- Prevention of CMV infections after transplant
- Severe complications of EBV
IV/oral
```
