Common Causative Organisms And Diseases

Question 1

What organisms can cause cellulitis?

Answer 1

Staphylococcus aureus or streptococcus pyogenes.

Question 2

What colour is gram positive on a gram stain?

Answer 2

Violet.

Question 3

What organism commonly causes tonsillitis?

Answer 3

Streptococcus pyogenes.

Question 4

What is the main causative organism of sepsis?

Answer 4

Neisseria meningitidis.

Question 5

What 2 organisms can cause a UTI?

Answer 5

E. Coli or Candida albicans.

Question 6

What organisms commonly infect patients having chemotherapy?

Answer 6

Shingles or Candida albicans.

Question 7

What causes shingles?

Answer 7

Reactivation of the varicella zoster virus.

Question 8

What organism is likely to have caused a skin abscess?

Answer 8

Staphylococcus aureus.

Question 9

How would you test for neisseria meningitidis?

Answer 9

Nasopharyngeal swab (as it is a commensal of the nasopharynx).

Question 10

Name a virulence factor of neisseria meningitidis.

Answer 10

Lipopolysaccharide capsule.

Question 11

Which bacteria commonly forms a biofilm and infects prosthetics?

Answer 11

Staphylococcus epidermidis.

Question 12

Which bacterial infection is associated with antibiotic usage?

Answer 12

Clostridium difficile.

Question 13

What organism causes community acquired pneumonia?

Answer 13

Streptococcus pneumoniae.

Question 14

What can viridans streptococci cause?

Answer 14

Tooth decay, bacterial endocarditis.

Question 15

Which organism is a coccobacilli?

Answer 15

Haemophilius influenzae

Question 16

What organism is the most common cause of travellers diarrhoea?

Answer 16

Salmonella typhi

Question 17

What is Legionnaire’s disease and what causes it?

Answer 17

Form of atypical pneumonia, caused by Legionella pneumophilia

Question 18

What diseases can be caused by Epstein Barr virus?

Answer 18

Glandular fever, Hodgkin’s lymphoma, gastric lymphoma, nasopharyngeal lymphoma

Question 19

Name 3 opportunistic infections of HIV.

Answer 19

Oral candidiasis
Kaposi’s sarcoma
Pneumocystitis pneumonia

Question 20

What T cell count means that HIV has progressed to AIDS?

Answer 20

T cell count < 200.

Question 21

What organism is known as the ‘winter vomiting bug’?

Answer 21

Norovirus

Question 22

What is Candida albicans a commensal of?

Answer 22

Mouth and vagina.

Question 23

What can aspergillosis cause?

Answer 23

This fungi can cause acute infection of the lungs.

Question 24

Which bacteria is coagulase positive?

Answer 24

Staphylococcus aureus

Question 25

Name a coagulase negative bacteria.

Answer 25

Staph. Epidermidis

Question 26

What test can differentiate between staph. Aureus and other staphylococci?

Answer 26

Coagulase test - staph. Aureus is coagulase positive.

Question 27

Is strep. Pyogenes group A or group B strep?

Answer 27

Group A

Question 28

How is endocarditis commonly caused?

Answer 28

Viridans streptococci causes tooth decay and gets into the bloodstream via the gums - it can cause aortic valve stenosis and endocarditis.

Question 29

What organism causes schistosomiasis?

Answer 29

Helminth's parasitic worms.

Question 30

Name 3 organisms that can cause pharyngitis.

Answer 30

EBV Adenovirus Strep. Pyogenes

Question 31

What bacteria is an iron dependent organism?

Answer 31

E. Coli

Question 32

What is the purpose of lactoferrin in breast milk?

Answer 32

Binds iron, preventing the proliferation of iron-dependent E. coli - protects newborn's immune system.

Question 33

Which organisms cause otitis externa?

Answer 33

Pseudomonas or staph