Wk6 Vagina and Penis micro Flashcards
Dominant normal microbe of the vagina (and penis):
lactobacilli
3 ways lactobacilli provide defense against invading pathogens:
- decrease pH
- H2O2
- Bacteriocins
Lactobacilli rxn that decreases pH:
Glucose –> pyruvate
What do MCT’s do?
excrete H+ with lactate to increase extracellular pH
What is a bacteriocin?
bacteria produced antibacterial
Cause of bacterial vaginosis?
disruption of normal flora
Must abundant bacteria in bacterial vaginosis?
Gardnerella
Tx for bacterial vaginosis?
metronidazole
Mech of metronidazole?
- interfere’s with bacteria’s fuel metabolism
2. generates reactive nitrogen –> damages nucleic acids
Only bugs that can activate metronidazole?
anaerobes
“clue cells”
PID
What change occurs in the epithelial cell surfaces in PID?
loss of cilia
Most common causes of PID
N. gonorrhea
Chlamydia
Tx for PID:
ceftriaxone + doxycycline
Bug causing most toxic shock syndrome?
S. aureus
S. aureus VF for TSS?
superantigen (TSST-1)
Mech of disease for S. aureus superantigen?
bind T-cells and Mac’s — activates ALL T-cells
Will you see bacteremia in TSS?
no – only toxin has desseminated systemically
HOw do some S. aureus get TSST-1?
SaPI1 pathogenicity island from bacteriophages
What’s it called when a bacteria gets some DNA from a phage?
transduction
DO patient’s with S. aureus sepsis get TSS?
not usually
Prevention of HIV in males associated with?
curcumcision
**shifts normal microbiota away from anaerobes to more aerobes – less inflammation – less Mac’s to infect
Where does HIV infect the penis?
urethra and inner foreskin
**no keratinized epithelium
First cells infected by HIV?
Mac’s
