What are the symptoms and treatment options for bacterial vaginosis?

Bacterial Vaginosis: Symptoms and Treatment

Bacterial vaginosis (BV) is characterized by a homogeneous, white, non-inflammatory discharge that adheres to vaginal walls, fishy odor (especially after adding KOH), vaginal pH greater than 4.5, and the presence of clue cells on microscopic examination. 1

Symptoms of Bacterial Vaginosis

BV occurs when normal hydrogen peroxide-producing lactobacilli in the vagina are replaced by high concentrations of anaerobic bacteria, Gardnerella vaginalis, and Mycoplasma hominis. Key symptoms and signs include:

• Vaginal discharge characteristics:

  • Homogeneous, white discharge that smoothly coats vaginal walls 2
  • Non-inflammatory in nature 2
  • Often thin in consistency 3

• Odor:

  • Fishy or musty odor, especially noticeable after intercourse or during menstruation 1
  • Positive "whiff test" - fishy odor becomes more pronounced when 10% KOH is added to vaginal discharge 2

• Other clinical findings:

  • Elevated vaginal pH (>4.5) 2, 1
  • Presence of clue cells (epithelial cells covered with bacteria) on microscopic examination 2, 1
  • Absence of significant inflammation 2

• Important note: Approximately 50% of women with BV are asymptomatic despite meeting clinical criteria for the condition 1, 4

Diagnosis

Diagnosis is based on meeting at least 3 of 4 Amsel criteria:

1. Homogeneous, white discharge adhering to vaginal walls
2. Vaginal pH > 4.5
3. Positive whiff test (fishy odor with KOH)
4. Presence of clue cells on microscopy 2, 1

Alternatively, Gram stain (Nugent score ≥4) showing markedly reduced lactobacilli morphology and predominance of Gardnerella morphotype can confirm diagnosis 1, 5.

Treatment Options

First-line Treatment Options:

1. Metronidazole regimens:

   • Oral metronidazole 500 mg twice daily for 7 days (95% cure rate) 1
   • Metronidazole gel 0.75% intravaginally once daily for 5 days 1

2. Clindamycin regimen:

   • Clindamycin cream 2% intravaginally at bedtime for 7 days 2, 1

3. Alternative regimen:

   • Metronidazole 2g orally in a single dose (84% cure rate) 2, 1
   • Tinidazole 2g once daily for 2 days or 1g once daily for 5 days 5

Important Treatment Considerations:

• Patients using metronidazole should avoid alcohol during treatment and for 24 hours afterward 2, 1
• Clindamycin cream is oil-based and may weaken latex condoms and diaphragms 1
• Treatment of male sexual partners is not recommended as it does not influence treatment response or recurrence rates 2, 1
• High recurrence rate (50-80% within one year) is common despite appropriate treatment 6

Special Considerations

Pregnancy:

• BV during pregnancy is associated with adverse pregnancy outcomes 2
• Treatment may be considered for high-risk pregnant women (those with history of preterm delivery) even if asymptomatic 2

Before Invasive Procedures:

• Consider treatment before surgical abortion procedures as BV has been associated with post-abortion PID 2
• BV has been linked to complications after gynecologic procedures including endometrial biopsy, hysterectomy, and IUD placement 2

Recurrent BV:

• Extended course of metronidazole (500 mg twice daily for 10-14 days) is recommended for recurrent cases 7
• If ineffective, metronidazole vaginal gel 0.75% for 10 days, followed by twice weekly for 3-6 months can be used 7
• Newer approaches being investigated include probiotics, vaginal microbiome transplantation, pH modulation, and biofilm disruption 6

Prevention Strategies

• Avoid douching 1
• Consider consistent condom use 6
• Smoking cessation may help reduce risk 6
• Hormonal contraception may offer some protection 6

By understanding the symptoms and following appropriate treatment regimens, most cases of bacterial vaginosis can be effectively managed, though patients should be counseled about the high likelihood of recurrence.