Bacterial vaginosis Flashcards
Is Bacterial Vaginosis a sexually transmitted disease?
- it’s non-sexually transmitted disease
- it occurs due to disturbance of a normal vaginal flora → vaginal pH is increased
Pathophysiology of Bacterial Vaginosis (BV)
disruption of a normal vaginal flora → lactobacilli reduce in number → other bacteria can grow freely as pH raises
What’s the role of lactobacillus?
Lactobacilli:
- large rod-shaped organisms
- produce hydrogen peroxide to help maintain the acidic pH of the vagina <4.5 hence inhibiting the growth of other microorganisms.
3 most common organisms that grow when lactobacilli is reduced
- Gardnerella Vaginallis
- anaerobes
- mycoplasma
Risk factors for BV infection
Many risk factors for BV are those associated with a change in the normal vaginal flora:
- Sexual activity – particularly a new partner or multiple sexual partners
- The use of a contraceptive intrauterine device (IUD)
- Receptive oral sex
- Presence of an STI
- Vaginal douching, or the use of scented soaps/vaginal deodorant
- Recent antibiotic use
- Ethnicity – more common in black women
- Smoking
Signs and symptoms of BV
50% asymptomatic
Symptoms:
- offensive, fishy smelling discharge
- usually no soreness, itchiness or irritation
Signs:
- Thin, white/grey, homogenous /jednordny/ vaginal discharge
Differences in discharge in:
- Candidiasis
- Trichomonas vaginalis
- Bacterial Vaginosis
- Vaginal Candidiasis – profuse thick white, itchy curd-like discharge
- Trichomonas vaginalis – thin, frothy /spieniony/, offensive discharge, with associated irritation, dysuria and vaginal inflammation
- Bacterial vaginosis - thin, white/grey homogenous, offensive/ fishy smelling’ usually no sore, itch or irritation
What does Dx of BV relies on? (3)
- history
- examination (vaginal)
- microscopy
What can be seen on microscopy with BV? (3)
High vaginal smear (HVS) is gram stained and evaluated for:
- ‘clue cells’
- reduced number lactobacilli
- absence of pus cells
What are clue cells?
Clue cells
vaginal epithelial cells coated with gram variable coccobacillus e.g. Gardnerella vaginalis or other anaerobic bacteria causing BV
What else, apart from microscopy, may be diagnostic of BV?
- diagnosis can also be made based on a vaginal pH >4.5
- KOH whiff test – whereby the addition of alkali (KOH) to the vaginal discharge causes release of a strong fishy odour (rarely done in practice)
Management of bacterial vaginosis
- asymptomatic → may not have any treatment
- Metronidazole (oral or intravaginal gel)
- Clindamycin or Tinidazole can also be used
Advice (apart from drug Rx) given to a woman diagnosed with BV
- avoid vaginal douching, scented shower gels, antiseptic agents and shampoos in the bath
- removal of an IUD that may be contributing to the BV should also be considered
Prognosis for BV
- symptoms usually resolve with treatment, and so a follow up test of cure is not necessary.
- recurrent BV can occur, with more than half of successfully treated women finding that symptoms have returned, usually within three months
Can BV cause complications in pregnancy?
Untreated symptomatic BV can increase the risk of pregnancy-related complications such as:
- premature birth
- miscarriage
- chorioamnionitis
What’s that?
Bacterial Vaginosis
