[6] Bacterial Vaginosis Flashcards
What is bacterial vaginosis?
A non-sexually transmitted infection of the lower genital tract in females
How common is bacterial vaginosis?
The most common cause of abnormal vaginal discharge in women of childbearing age
What happens to the normal vagina to lead to bacterial vaginosis?
There is a disturbance in the normal vaginal flora leading to a reduction in the number of lactobacilli bacteria
What type of bacteria are lactobacilli?
Large rod-shaped organisms that produce hydrogen peroxide to help maintain the acidic pH of the vagina
What is the normal pH of the vagina?
< 4.5
What is the result of the acidic nature of the vagina?
Prevents overgrowth of other microorganisms
What happens to the pH of the vagina when lactobacilli numbers are reduced?
pH increases
What does the increase in pH in bacterial vaginosis allow?
Overgrowth of other microorganisms
What are the most common organisms found in bacterial vaginosis?
- Gardnerella vaginalis
- Anaerobes
- Mycoplasmas
What are the risk factors for bacterial vaginosis?
- New or multiple sexual partners
- Use of IUD
- Receptive oral sex
- Presence of STI
- Vaginal douching
- Use of scented soaps/vaginal deodorants
- Recent antibiotic use
- Black ethnicity
- Smoking
What % of bacterial vaginosis cases are asymptomatic?
Up to 50%
What is the most common symptom of bacterial vaginosis?
Offensive, fishy smelling discharge
What symptoms are NOT usually associated with bacterial vaginosis?
- Soreness
- Itching
- Irritation
What are the examination findings in bacterial vaginosis?
Thin, white/grey homogenous vaginal discharge
What are the differentials for bacterial vaginosis?
- Other vaginal infections
- Other benign causes of vaginal discharge
- Tumours of the vulva, vagina, cervix or endometrium
- Atrophic vaginitis
What other vaginal infections can be differentials for bacterial vaginosis?
- Candida
- Trichomoniasis
- Chlamydia
- Gonorrhoea
- Herpes simplex
What benign causes of vaginal discharge are differentials for bacterial vaginosis?
- Physiological discharge
- Chemical irritants
- Foreign body
- Pregnancy
- Cervical ectropion
How is bacterial vaginosis diagnosed?
- History
- Vaginal examination
- Microscopy
How is a sample obtained for microscopic testing for bacterial vaginosis?
High vaginal swab
What will be seen on gram stained microscopy of bacterial vaginosis?
- Clue cells
- Reduced number of lactobacilli
- Absence of pus cells
What are the clue cells seen in bacterial vaginosis?
Vaginal epithelial cells studded with gram variable coccobacilli
Isolation of what is not sufficient to diagnose bacterial vaginosis?
Gardnerella vaginalis
Why is isolation of Gardnerella vaginalis not diagnostic of bacterial vaginosis?
It can be cultured from 50% of uninfected women
What are some other diagnostic investigations for bacterial vaginosis?
- pH >4.5
- KOH Whiff test
What is the KOH Whiff test for bacterial vaginosis?
Addition of potassium hydroxide (KOH) causes vaginal discharge to release a strong fishy odour
Do asymptomatic bacterial vaginosis patients require treatment?
Only if they are pregnant
What is the most common treatment for bacterial vaginosis?
Metronidazole
What regimes of metronidazole are available for bacterial vaginosis?
- 400mg BD for 5-7 days
- OR single dose of 2g
- OR gel applied to vagina
What are the alternative antibiotics for bacterial vaginosis?
- Clindamycin
- Tinidazole
How should breastfeeding women be treated for bacterial vaginosis?
Vaginal metronidazole
What should patients avoid after diagnosis of bacterial vaginosis?
- Vaginal douching
- Scented shower gels
- Anti-septic agents
- Shampoos in bath
What should be considered if bacterial vaginosis is present with an IUD?
Removal of IUD
What % of people with bacterial vaginosis have return of symptoms within 3 months of treatment?
> 50%
What are the complications of bacterial vaginosis following TOP?
- Endometriosis
- PID
What are the potential complications of bacterial vaginosis in pregnancy?
- Late miscarriage
- Preterm delivery
- Premature rupture of membranes
- Low birth weight
- Post partum endometriosis
What is a potential complication of bacterial vaginosis in all women?
Can increase the risk of acquiring HIV and other STIs
