09.1 Microbiology of the GI Tract

Question 1

What are obligate anaerobes?

Answer 1

Die in the presence of oxygen

Examples include bactericides fragilis and chlorstridial organisms

Question 2

What are facultative anaerobes?

Answer 2

Prefer O2 but can live without it

Examples include E. coli and staphylococci

Question 3

What positive things can bacteria have on the gut?

Answer 3

Synthesise and excrete vitamins (K, B12 and Thiamine)
Prevent colonisation by pathogens
Kill non indigenous bacteria
Stimulate development of MALT
Stimulation of natural antibodies (bacteroides)

Question 4

What can chlostridium perfringens cause?

Answer 4

Wet/gas gangrene

Question 5

What is travelers diarrhoea?

Answer 5

Three or more unformed stools passed by a traveler within 24 hours

Question 6

What is the main cause of traveller’s diarrhoea?

Answer 6

Enterotoxic E. coli

Others include Shigella spp, salmonella spp, vibrio cholerae

Question 7

What are obligate aerobes?

Answer 7

Must have oxygen

Examples are pseudomonas and TB