Human flora

Question 1

What is Normal Flora?

Answer 1

Microorganisms that’s live on another living organism without causing disease

Permanent/fixed microorganisms in particular anatomical sites in healthy human body

Question 2

What can alter the composition of NF

Answer 2

1) local envt. (Ph/temperature)
2) age/hormones
3) mode of birth
4) dietary/cultural habits
5) anti microbial use
6) lifestyle

Question 3

What are the main types of human body flora?

Answer 3

1) Resident/Normal Flora
2) Transient Flora

Question 4

Talk briefly about Resident Flora

Answer 4

1) reside within stratum corneum
2) relatively fixed
3) reestablishes itself when disturbed
4) can cause disease outside of its usual location

Question 5

Examples of Resident Flora

Answer 5

1) Staphylococcus Epidermidis
2) staphylococcus hominis
3) Malassezia species

Question 6

Talk briefly on Transient Flora

Answer 6

1) non pathogenic/potentially pathogenic
2) inhabit skin for hours/days/weeks
3) removed my routine surgical hand washing
4) acquired during HCWs contact with patients/beds, patient secretions

Question 7

Examples of Transient Flora

Answer 7

Staphylococcus aerus
Gram negative bacteria
Yeasts

Question 8

Relationships of NF & host

Answer 8

1) MUTUALISM - both benefit eg E.coli in gut receives nutrients & produces useful VitK
2) COMMENSALISM- one benefits, other neither benefits or is harmed
3) OPPORTUNISM- one takes advantage of the other

Question 9

Advantages of NF in health

Answer 9

(1) ecological niches
(2) prevents other more pathogenic bacteria from gaining foothold in body
(3) more efficient in competing for micronutrients
(4) gut bacteria responsible for its normal function & structure
(5) their metabolism produces vitamins esp B & K
(6) production of antibodies
(7) liberation of endotoxins
(8) production of bacteriocins

Question 10

Hallmarks of infection with members of the normal human flora

Answer 10

1) Caries - periodontal disease
2) abscesses, foul smelling discharge
3) endocarditis
4) peritonitis
5) urinary infection

Question 11

Value of bacterial flora of skin

Answer 11

10^2 - 10^4 organisms per cm^2

Question 12

Most common flora on the skin

Answer 12

1) Staph.Epidermidis
2) Diphtheroids
3) propionibacterium acnes (anaerobic GPB)
4) corynebacterium

Question 13

_ is often found in moist areas like axilla & groin

Answer 13

Coliforms

Question 14

Predominant organisms of the eye;

Answer 14

Moraxella spp
Diphtheroids
Staph Epidermidis
Nonhaemolytic streptococci

Question 15

What is the distribution of microorganisms in the GIT

Answer 15

1) Stomach - Low (10^3 - 10^6 orgs/g of content)
2) Duodenal - Sparse (0-10^3)
3) ileum - mixed (10^6 - 10^8 organisms/g)
4) large intestine - Dense(10^4 - 10^11)

Question 16

_ is the gatekeeper of the vaginal ecosystem

Answer 16

Lactobacillus aerophilius (btwn 4.5 +/- 5.0)

Absence = BV

Question 17

_ on the skin causes IV cannula infections

Answer 17

Staph Aerus

Question 18

Main organisms used as prebiotics

Answer 18

1) lactobacilli
2) bifidobacterium species
3) yeasts etc

Question 19

Probiotics

Answer 19

Contains live micro-organisms which when taken in adequate amounts alter the gut micro flora & confer health benefit on the host

Question 20

Prebiotics

Answer 20

Induce growth/activity of micro organisms that contribute to the well being of the host.