Management of Vaginal Discharge
The diagnosis of vaginal discharge requires measuring vaginal pH and performing microscopic examination to differentiate between the three most common causes—bacterial vaginosis, vulvovaginal candidiasis, and trichomoniasis—followed by targeted treatment based on the specific pathogen identified. 1
Diagnostic Algorithm
Initial Office-Based Testing
Measure vaginal pH using narrow-range pH paper applied directly to vaginal secretions: pH >4.5 indicates bacterial vaginosis or trichomoniasis, while pH ≤4.5 suggests vulvovaginal candidiasis 1, 2
Perform saline wet mount microscopy to identify motile trichomonads (trichomoniasis) or clue cells (bacterial vaginosis) 3, 1
Perform 10% KOH preparation to identify yeast or pseudohyphae (candidiasis); the KOH disrupts cellular material that might obscure fungal elements 3, 1
Conduct whiff test: A fishy odor immediately after applying KOH confirms bacterial vaginosis or trichomoniasis 3, 1
Common pitfall: Avoid treating based on symptoms alone, as discharge characteristics overlap significantly between conditions and microscopy is essential for accurate diagnosis 4, 5
Treatment by Specific Diagnosis
Bacterial Vaginosis
Clinical criteria require 3 of 4 findings: homogeneous white noninflammatory discharge adhering to vaginal walls, clue cells on microscopy, vaginal pH >4.5, and positive whiff test 3
Recommended Treatment:
- Metronidazole 500 mg orally twice daily for 7 days (95% cure rate, preferred regimen) 1
- Alternative: Metronidazole 2 g orally as single dose 3
- Alternative: Clindamycin 2% cream intravaginally 3
- Alternative: Metronidazole gel 0.75% intravaginally 6
Critical point: Only treat symptomatic bacterial vaginosis; asymptomatic cases do not require treatment unless the patient is undergoing surgical abortion or other invasive uterine procedures 3
Partner management: Do not treat male sexual partners, as this does not prevent recurrence 3, 1
Important caveat: Patients must avoid alcohol during metronidazole treatment and for 24 hours after completion 3
Vulvovaginal Candidiasis
Diagnostic features: Pruritus, vulvovaginal erythema, white discharge, normal pH (≤4.5), and visualization of yeast or pseudohyphae on KOH preparation 3, 2
Recommended Treatment:
- Fluconazole 150 mg orally as single dose (55% therapeutic cure rate, standard treatment) 3, 1
- Alternative intravaginal options: Clotrimazole, miconazole, terconazole, or butoconazole in various formulations for 1-7 days 3
For recurrent vulvovaginal candidiasis (≥4 episodes/year):
- Initial treatment with 7-14 day course of topical azole or fluconazole 7
- Followed by maintenance therapy: Fluconazole 150 mg weekly for 6 months 1, 7
Critical pitfall: Do not treat asymptomatic Candida colonization, which occurs in 10-20% of women; treatment is only indicated when symptoms are present 3, 7
Partner management: Partner treatment is not recommended for candidiasis 1
Trichomoniasis
Clinical presentation: Yellow-green discharge, malodor, vulvovaginal irritation, pH >4.5, and motile trichomonads on saline wet mount 3, 7
Recommended Treatment:
- Metronidazole 2 g orally as single dose (90-95% cure rate) 3, 1
- Alternative: Tinidazole 2 g orally as single dose (92-100% cure rate) 8
Essential requirement: Sexual partners must be treated simultaneously to prevent reinfection 3, 1
Important instruction: Patients and partners should avoid sexual contact until both complete therapy and are asymptomatic 3
Special Populations
Pregnant Women
- Use only 7-day topical treatments for bacterial vaginosis and candidiasis; avoid oral agents in first trimester 1, 7
- Metronidazole 2 g single dose is acceptable for trichomoniasis in pregnancy 3
HIV-Infected Women
Follow-Up Recommendations
Return only if symptoms persist after treatment or recur within 2 months; routine test-of-cure is not necessary if symptoms resolve 1, 7
Recurrence of bacterial vaginosis is common (50-80% within one year) but does not change initial management approach 1
Critical caveat: Women with persistent symptoms after over-the-counter antifungal treatment should seek medical evaluation, as self-diagnosis is often inaccurate 3, 7