Microbiology

Question 1

Name 3 gram positive cocci:

Answer 1

Staphylococcus, streptococcus, enterococcus

Question 2

Name 4 gram positive bacilli:

Answer 2

Listeria, clostridium, bacillus, corynebacterium

Question 3

Name a gram negative cocci:

Answer 3

Neisseria

Question 4

Name 5 gram negative bacilli:

Answer 4

E. coli, Klebsiella, salmonella, pseudomonas, bacteroides.

Question 5

Which drugs inhibit cell wall synthesis?

Answer 5

Beta-lactams: penicillins, cephalosporins, carbapenems.

Glycopeptides: vancomycin, teicoplanin

Question 6

Which drugs inhibit protein synthesis?

Answer 6

Amino glycosides: gentamicin, tobramycin
Tetracyclines: doxycycline
Lincosamides: clindamycin
Macrolides: azithromycin
Fusidic acid
Linezolid

Question 7

Which drugs are inhibitors of nucleic acid synthesis?

Answer 7

Folic acid synthesis inhibitor: trimethoprim, sulphonamides.
Fluroquinolones: ciprofloxacin
Rifampicin
Metronidazole

Question 8

Name 3 agents which cause atypical pneumonia?

Answer 8

Legionella haemophilia, Coxiella burnetii (Q fever),

Mycoplasma

Question 9

How can you differentiate typical and atypical pneumonia?

Answer 9

Atypical pneumonia: typically sick with non resp symptoms for longer. ~ 4 days of malaise and fevers before cough and SOB etc.

Question 10

What gram stain is a more likely result for hospital acquired pneumonia?

Answer 10

Gram -

Question 11

What is the commonest cause of typical pneumonia?

Answer 11

Strep. Pneumoniae

Question 12

In which people is it difficult to differentiate between typical and atypical pneumonia?

Answer 12

V. Young and v. Old

Question 13

What are 4 narrow spectrum penicillins?

Answer 13

Penicillin G - benzylpenicillin
Penicillin V - phenoxymethylpenicillin (available orally)
Procain penicillin
Benzathine penicillin (IM)

Question 14

Name 2 moderate spectrum penicillins

Answer 14

Amoxicillin and ampicillin

Question 15

Name 2 broad spectrum penicillins, when you would give them, and how.

Answer 15

Piperacillin and ticarcillin.
Give if px is very sick or pseudomonas aeruginosa infection is suspected. Often combined with beta lactamases.
IV

Question 16

Name 2 organisms that produce beta-lactamases and 2 beta lactamase inhibitors.

Answer 16

Staph aureus and Klebsiella.

Tazobactam and clavulanic acid.

Question 17

What is augmentin?

Answer 17

Amoxycillin- clavulanate

Question 18

If you have EBV, you’re on penicillin, and you develop a rash, is it definitely an allergic reaction to penicillin?

Answer 18

No

Question 19

If a px becomes anaphylactic to penicillin, what drugs should you use instead?

Answer 19

Cephtriaxone, fluroquinolone

Question 20

Which group of bacteria are intrinsically resistant to cephalosporins?

Answer 20

Enterococci

Question 21

Which antibiotics have intracellular activity and when are they used?

Answer 21

Tetracyclines - doxycycline.
Macrolides - azithromycin
Fluroquinolones - ciprofloxacin
Used against strep. pneumoniae, atypical pneumonia or in case of allergies.

Question 22

Which antibiotics are anti-staphylococcal penicillins?

Answer 22

Flucloxycillin, methicillin, dicloxacillin

Question 23

Anti-staphylococcal cephalosporins?

Answer 23

Cephazolin IV/IM
Cephalothin IV/IM
Cephalexin PO

Question 24

What is the incubation fever of typhoid fever?

Answer 24

2-3 weeks

Question 25

Which antibiotics have gram -ve activity?

Answer 25

• Beta lactams: moderate spectrum penicillins - Amoxycillin, 1st and 2nd generation cephalosporins - cephazolin.
• Penicillin/beta lactamase combinations.
• 3rd and 4th gen cephalosporins
• Gentamycin
• Fluroquinolones

Question 26

What is metronidazole used for?

Answer 26

Anaerobes

Question 27

What do you prescribe if enterococcus infection is suspected?

Answer 27

Ampicilin

Question 28

If someone develops diarrhoea, abdominal pain and fever after antibiotic treatment, what should you suspect?

Answer 28

Clostridium Difficile

Question 29

Why should you not prescribe Aminoglycosides unless really necessary?

Answer 29

Risk of reversible tubular damage to kidneys and irreversible inner ear damage.

Question 30

When should you treat asymptomatic bacteruria?

Answer 30

When px is pregnant or undergoing urological procedure.

Question 31

Where does staph aureus love to infect?

Answer 31

Bones, especially the back.

Question 32

When do you give vancomycin orally?

Answer 32

For clostridium difficile infection. It isn’t absorbed and goes straight to the gut.

Question 33

What are recurrent rigors commonly caused by?

Answer 33

Bacterial infection

Question 34

What could be a cause of severe muscle pain, even without fever?

Answer 34

Sepsis

Question 35

What is fever in the elderly rarely caused by?

Answer 35

Viruses

Question 36

Sepsis in the elderly man may not present with…

Answer 36

Fever- the older the colder

Question 37

What is a medical emergency worse than a septic px with fever?

Answer 37

One with hypothermia

Question 38

If a px has fever post-operatively, what is the most likely cause?

Answer 38

The surgery

Question 39

What symptoms are rarely displayed in viral hepatitis?

Answer 39

Jaundice in a febrile px.

Question 40

Generalised rashes that also include the hands and the feet are likely to be caused by…

Answer 40

Viral infection, drugs, rickettsial infections or Syphilus.

Question 41

What disease needs to be excluded from a febrile patient returning from SE Asia or Africa?

Answer 41

Malaria

Question 42

Staph aureus in the urine is a sign of what, until proven otherwise?

Answer 42

Staphylococcal bacteremia

Question 43

What should you think of in a px complaining of acute sore throat, trouble swallowing and/or hoarse voice?

Answer 43

Acute Bacterial epiglottitis

Question 44

What should you think of in a febrile px with back pain?

Answer 44

Vertebral osteomyelitis and epidural abscess.

Question 45

How do you confirm viral meningitis?

Answer 45

PCR