Genital Tract Infections - Bacterial Vaginosis

Question 1

What is Bacterial Vaginosis?

Answer 1

Overgrowth of anaerobic bacteria in the vagina - not an STI.

Question 2

Epidemiology of Bacterial Vaginosis.

Answer 2

Seen exclusively in sexually active women (though it isn’t an STI).

Question 3

Aetiology of Bacterial Vaginosis.

Answer 3

Loss of Lactobacilli in Vagina.

Question 4

Physiology of Vaginal Flora.

Answer 4

1. Lactobacilli - main component of healthy bacterial flora.
2. Produce Lactic Acid to keep Vaginal pH low (under 4.5).
3. Acidic Environment - prevents growth of other bacteria.

Question 5

Pathophysiology of Bacterial Vaginosis.

Answer 5

1. Reduced Numbers of Lactobacilli.
2. pH rises.
3. Alkaline Environment - Anaerobic Bacteria multiply.

Question 6

Species Associated with Bacterial Vaginosis (3).

Answer 6

GMP :

1. Gardnerella vaginalis (commonest).
2. Mycoplasma hominis.
3. Prevotella species.

Question 7

Risk Factors of Bacterial Vaginosis.

Answer 7

1. Multiple Sexual Partners.
2. Excessive Vaginal Cleaning (Douching, Use of Cleaning Products, Vaginal Washes).
3. Recent Antibiotics.
4. Smoking.
5. Copper Coil.

Question 8

Protective Factors of Bacterial Vaginosis.

Answer 8

1. COCP.

2. Condom Use.

Question 9

Clinical Features of Bacterial Vaginosis.

Answer 9

1. ‘FISHY-SMELLING’ Watery-Grey/White Vaginal Discharge.

2. 50% Asymptomatic.

Question 10

Clinical Features that Suggest Other Causes.

Answer 10

1. Itching.
2. Irritation.
3. Pain.

Question 11

Investigations of Bacterial Vaginosis.

Answer 11

1. Speculum Examination with High Vaginal Swab (not necessary if typical symptoms and low risk of STIs).
2. Vaginal pH (Swab and pH Paper).
3. Vaginal Swab + Microscopy (High Vaginal during Speculum or Low Vaginal Self-Taken).

Question 12

Vaginal pH and Abnormal Results.

Answer 12

1. Normal : 3.5-4.5.

2. Bacterial Vaginosis : 4.5+.

Question 13

Microscopy Results of Bacterial Vaginosis.

Answer 13

CLUE CELLS - Stippled Squamous Epithelial Cells from the cervix that have bacteria stuck inside them - coated with large amounts of bacilli.

Question 14

Diagnostic Criteria of Bacterial Vaginosis.

Answer 14

Amsel’s Criteria (at least 3/4) :

1. Thin White Homogenous Discharge.
2. Clue Cells on Microscopy.
3. Vaginal pH > 4.5.
4. Positive Whiff Test.

Question 15

What is Whiff Test?

Answer 15

Addition of Potassium Hydroxide results in fishy odour.

Question 16

Management of Bacterial Vaginosis.

Answer 16

1. Asymptomatic - No Treatment.
2. Antibiotic of Choice : ORAL or Vaginal Gel Metronidazole 5-7 days (Targets : Anaerobic bacteria).
3. Alternative : Clindamycin.

Question 17

Additional Management in Bacterial Vaginosis.

Answer 17

1. Assess Risk of Additional Pelvic Infections e.g. Swabs.

2. Advice and Information on Risk Factors.

Question 18

Important Consideration of Metronidazole Antibiotic.

Answer 18

Avoid Alcohol whilst on Metronidazole - Risk of Disulfiram-Like Reaction :

1. Nausea and Vomiting.
2. Flushing.
3. Severe Symptoms of Shock and Angioedema.

Question 19

Main Complication of Bacterial Vaginosis.

Answer 19

Increased Risk of Developing STIs.

Question 20

Complications of Bacterial Vaginosis in Pregnancy (6).

Answer 20

1. Miscarriage.
2. Preterm Delivery.
3. Premature Rupture of Membranes.
4. Chorioamnionitis.
5. Low Birth Weight.
6. Postpartum Endometritis.