9.1 Microbiology of the GI tract

Question 1

Where in the GI tract is anaerobic?

Answer 1

Deep tongue, small bowel, colon

Question 2

What are the functions of colonic bacteria?

Answer 2

Excrete vitamins eg. vitamin K and B12
Prevent colonisation by pathogens
Kill non-indigenous bacteria
Stimulate the natural production of antibodies

Question 3

Name 3 pathogens found naturally in the mouth

Answer 3

Streptococci
Staphylococci
Lactobacillus
Candida

Question 4

What causes oral thrush?

Answer 4

Candida albicans

Question 5

What is parotitis?

Answer 5

Swollen parotid glands caused by a S. aureus infections

Question 6

Name 2 bacteria present in the throat

Answer 6

Neisseria meningitidis

Strep viridans

Question 7

What are the cause of 70% of tonsilitis?

Answer 7

Viruses- adenovirus and rhinovirus

Question 8

What is a common bacteria found in the stomach?

Answer 8

H. pylori

Question 9

Name 2 bacteria always present in the colon

Answer 9

E.coli

Bacteroides fragilis

Question 10

Why are prophylactic antibiotics given before GI surgery?

Answer 10

To reduce the chance of wound infections

Question 11

Give 2 examples of bacteria that live on the perineal skin

Answer 11

E.coli

Lactobacillus