3.7 Commensal Flora of the Genitals

Question 1

What key factors determine the composition of the commensal microflora?

Answer 1

Local defenses (innate ad acquired) 
Temperature 
pH 
Availability of oxygen 
sources of nutrients (host secretions, dead cells, metabolites produced by other members of commensal flora)

Question 2

What are the local defences of the Genitals?

Answer 2

Cervical mucociliary escalator
Mucus (contains antimicrobial proteins, serves as source of microbial nutrients, protects cells from microbial adhesions, serves as a target for microbial adhesions)

Question 3

What is the availability of oxygen in the genitals?

Answer 3

Microaerophilic (2% of typical air)

Question 4

What factors affect the availability of air in female genitals?

Answer 4

Hormones, tampons, contraceptives

Question 5

What are the energy and nutrient sources of the female genitals?

Answer 5

mucus, vaginal fluid, menstrual fluid, glycogen (only in reproductive years) and sexual fluids

Question 6

Describe lactobacilli

Answer 6

Gram positive, non spore forming, non motile, obligate anaerobe, acidophilic, mesophilic
COMMENSAL

Question 7

What is associated with decreased lactobacilli in the vagina?

Answer 7

vaginal candidiasis and bacterial vaginosis

Question 8

What is the most common cause of vaginal candidiasis

Answer 8

Candida albicans (yeast)

Question 9

What can be caused as a result of candida albicans?

Answer 9

vulvovaginitis/vagintis

Question 10

what are the risk factors for candida vaginitis?

Answer 10

recent antibiotic therapy 
pregnancy 
hormone replacement (OCT,HRT) 
diabetes (more glucose) 
use of condoms 
frequent sexual activity

Question 11

Symptoms and diagnosis for candida vaginitis

Answer 11

inflammation, burning, itching and cheesy discharge

Question 12

treatment o candida vaginitis

Answer 12

change reversible factors, topical or oral antifungal agents

Question 13

What factors can lead to bacterial vaginosis?

Answer 13

decrease/change in lactobacilli 
onset of menses 
use of vaginal medications 
use of spermicides 
increased number/frequency f of sexual partners/intercourse and oral sex

Question 14

Symptoms and diagnosis of bacterial vaginosis

Answer 14

Excessive malodorous vaginal discharge (metabolic activities of anaeroves may be implicated in iritation)
Whiff test (fishy odour)
pH > 4.5
Loss of lactobacilli
increase in gram variable coccobacilli
clue cells - squamous cells coated with bacteria

Question 15

treatment of bacterial vaginosis

Answer 15

Metronidazole

Clindamycin

Question 16

How can foetal infections occur?

Answer 16

Haematogenous dissemination
direct infection by endogenous or exogenous pathogens
Infection during delivery

Question 17

What does group B strep cause in newborns? and which strep?

Answer 17

neonatal septicemia and meningitis

Strep. agalactiae

Question 18

How does group B strep cause infection in babies?

Answer 18

Able to traverse the placental membranes and may lead to rupture/pre term birth and may access the foetal lungs though aspiration of infected amniotic fluid or neonatal lungs via aspiration of vaginal fluid during delivery

Question 19

What is the commensal flora of the female genital tract?

Answer 19

Lactobacilli