Bacterial Vaginosis and Yeast Flashcards
Vaginitis?
Inflammation of the vaginal epithelium
Chlamydia and gonorrhea usually present how?
Cervicitis - inflammation of the endocervix with mucopurulent discharge
This is the case unless the female is pre-pubescent or post menopausal.
Besides cervicitis, how can chlamydia and gonorrhea present?
Urethritis with mucopurulent discharge. We see this in men and women.
Vaginosis?
Distinct syndrome of vaginal irritation, pruritis, and odor generally without a PMN response (this is key)
Candidiasis?
Inflammation associated with overgrowth of the yeast Candida Albicans
Trichomoniaisis??
Vaginal inflammation associated with infection by Trichomonas vaginalis
What sign and symptoms do we associate with Bacterial Vaginosis?
- Lower abdominal pain
- Pruritis
- Red vaginal wall and labia
- Thin grayish/white discharge
- Odor
There is significant impact on reproductive health with Bacterial Vaginosis. What are they?
- Preterm delivery
- Increased fetal mortality
- Postpartum infection
- Post surgical infection
- Increased risk of STDS
Bacterial vaginosis is significant in effect due to the imbalance of normal flora. What causes this imbalance?
- Change in hormone status (high estrogen favors lactobacillus colonization)
- Change in sexual activity
- Antibiotic therapy/douching that alters normal flora
What microbiology do we see with bacterial vaginosis, secondary to these imbalances?
- Lots of lactobacilli, proliferation of other anaerobes
- Increased Mobiluncus species (anaerobe)
- Increased gardnerella vaginalis (facultative anaerobe)
Describe these numerous lactobacilli we see under histology
Large or pleomorphic gram POSITIVE rods
- Produce acid by fermentation
- Produce H2O2
Discuss the diagnostic findings for BV
- Elevated vaginal pH (normally 4-4.5)
- Clue cells (epithelial cells coated with small gram + rods accompanied by infrequent inflammatory cells)
- Amine odor (Whiff test with 10% KOH)
- Culture positive for Gardnerella vaginalis (beta hemolytic susceptible to metronidazole disk)
Symptoms of yeast infection and how we distinguish it from BV
- Vulvo-vaginal itching
- Discharge (thick, white)
- Burning on urination
Difficult ti distinguish. Yeast are not pH sensitive (they like the acid) and will have hyphae on staining.
What is the structure of trichomonas vaginalis? How does it replicate? How do we describe it?
- Flagellated protozoan that is an aerotolerant anaerobe
- Replicates by binary fission (no cyst stage)
BV and Trichomoniasis have many similarities. However, they have one important difference. What is it?
They both increase vaginal pH, disturb the normal flora, give similar symptoms of abdominal pain and itching and discharge, and both cause similar reproductive risks of premature birth, post partum complications and increased risk of other STDs.
HOWEVER, Trichomoniasis gives us an inflammatory response.
Link HIV to the inflammatory response in Trichomoniasis:
- Intense cell mediated response causes recruitment of CD4+ lymphocytes susceptible to HIV.
- Presence of pinpoint hemorrhaging in vaginal mucosa increases access of virus to host
- T. vag degrade secretory leukocyte protease inhibitor (a product known to block HIV cell attachment)
- Trichomonas infection increases shedding of HIV in women and men
We have this T-cell mediated response to Trichomonas! Yay! That means we can develop protective immunity right?!
Nope.
Reinfection with other strains occurs due to phase variation among T. vaginalis surface molecules (cysteine proteases and adhesins).
Phase variation in surface antigens is augmented by T. vaginalis infection with dsRNA viruses.
Proteinases are produced that digest antibodies.
How do we diagnose Trichomoniasis?
- Visualize motile protozoans on wet mount
- Dip stick
- PCR
- Cx - 48-72 hours
Treating Trichomonas
You guessed it, metronidazole.
Alright so we seem to keep using this metronidazole thing. Describe its structure and how it works
Imidazole ring is a prodrug activated by reduction reactions, then attacking DNA. Due to the need for reduction, it works best where redox potential is really low, like with anaerobic bacteria and anaerobic protozoans like Trichomonas which have an organelle “hydrogenosome,” where anaerobic respiration occurs.
