CLINICAL PRINTABLE
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A one-page Vaginitis clinical reference is on the way.
1 · Recognition / Alarm Features
- Bacterial vaginosis (BV): most common cause of vaginal discharge in reproductive-age women. Thin, gray-white, homogeneous discharge with fishy odor (especially after intercourse). Minimal or no itching. Vaginal pH >4.5. Clue cells on wet prep. Positive whiff test (amine odor with KOH). Amsel criteria: 3 of 4 criteria required for diagnosis.
- Vulvovaginal candidiasis (VVC): thick, white, cottage cheese-like discharge. Vulvar pruritus and burning (often severe). Erythema and edema of vulva and vagina. Vaginal pH normal (3.8–4.5). Pseudohyphae or budding yeast on KOH prep. Risk factors: antibiotics, diabetes, immunosuppression, pregnancy, oral contraceptives.
- Trichomoniasis: STI caused by Trichomonas vaginalis. Yellow-green, frothy, malodorous discharge. Vulvovaginal pruritus and irritation. Cervical petechiae ('strawberry cervix') — pathognomonic but seen in only 2–5%. Vaginal pH >4.5. Motile trichomonads on wet prep (sensitivity 60–70%). NAAT is most sensitive (>95%). Treat sexual partners.
- Amsel criteria for BV (3 of 4): (1) thin, homogeneous, gray-white discharge; (2) vaginal pH >4.5; (3) positive whiff test; (4) clue cells on wet prep (>20% of epithelial cells). Nugent score (Gram stain) is the gold standard for research but not required clinically.
- Recurrent VVC: ≥4 episodes per year. Evaluate for diabetes, immunosuppression, and non-albicans Candida species (C. glabrata, C. krusei — resistant to azoles). Culture and speciation required for recurrent or refractory VVC. Maintenance fluconazole therapy for recurrent VVC.
2 · Differential / Secondary Causes
Atrophic vaginitis (genitourinary syndrome of menopause)
Postmenopausal women. Vaginal dryness, dyspareunia, burning, discharge. Thin, pale vaginal mucosa with loss of rugae. Vaginal pH >5. Treat with topical estrogen (vaginal cream, ring, or tablet) or ospemifene (oral SERM). Systemic estrogen is an alternative.
Cervicitis
Mucopurulent cervical discharge, cervical friability, cervical motion tenderness. Caused by Chlamydia trachomatis or Neisseria gonorrhoeae. NAAT for GC/Chlamydia. Treat with ceftriaxone + doxycycline. Test and treat sexual partners.
Contact/irritant vulvovaginitis
Vulvar pruritus, burning, erythema without discharge. Caused by soaps, detergents, feminine hygiene products, spermicides, latex. Normal pH and wet prep. Treat by identifying and removing the irritant. Topical hydrocortisone for inflammation.
Desquamative inflammatory vaginitis (DIV)
Purulent vaginal discharge, vaginal erythema, dyspareunia. Elevated pH, parabasal cells on wet prep, no clue cells or yeast. Treat with intravaginal clindamycin or hydrocortisone. Refer to gynecology for refractory cases.
3 · Treatment Pathway
BV — treatment
Metronidazole 500 mg PO BID for 7 days (first-line). Metronidazole 0.75% vaginal gel once daily for 5 days (equivalent efficacy). Clindamycin 2% vaginal cream once daily for 7 days (alternative). Treat symptomatic pregnant women — BV is associated with preterm birth. Partner treatment is not recommended for BV (not an STI). Recurrence is common (50% at 12 months).
VVC — uncomplicated
Topical azoles (clotrimazole, miconazole, terconazole): OTC, effective, 1–7 day regimens. Fluconazole 150 mg PO single dose: preferred for convenience. Equivalent efficacy to topical agents. Avoid fluconazole in pregnancy (teratogenic in first trimester). Treat sexual partners only if symptomatic balanitis.
VVC — recurrent
Induction: fluconazole 150 mg every 72 hours for 3 doses. Maintenance: fluconazole 150 mg weekly for 6 months. Evaluate for diabetes, immunosuppression, and non-albicans Candida. Culture and speciation for refractory cases — C. glabrata requires boric acid or flucytosine.
Trichomoniasis — treatment
Metronidazole 500 mg PO BID for 7 days (preferred over single 2 g dose — higher cure rate). Tinidazole 2 g PO single dose (alternative). Treat all sexual partners. Test of cure not routinely recommended. Rescreen at 3 months (high reinfection rate). Avoid alcohol during and 24 hours after metronidazole (72 hours after tinidazole).
4 · Expected Response
- BV: symptom resolution within 3–7 days of treatment. Recurrence rate 50% at 12 months — consider maintenance metronidazole gel twice weekly for recurrent BV.
- VVC: symptom relief within 24–48 hours of fluconazole. Complete resolution in 3–7 days. Persistent symptoms after treatment: consider non-albicans Candida or alternative diagnosis.
- Trichomoniasis: cure rate >90% with 7-day metronidazole. Reinfection is common — rescreen at 3 months.
5 · Escalation
- Trichomoniasis: test for other STIs (GC, Chlamydia, HIV, syphilis). Report to public health as required. Treat and test all sexual partners.
- Recurrent VVC not responding to fluconazole: culture and speciation. Non-albicans Candida (C. glabrata) requires boric acid 600 mg intravaginal daily for 14 days or flucytosine cream. Refer to gynecology.
- Metronidazole-resistant trichomoniasis: tinidazole 2 g daily for 5 days. Refer to infectious disease or gynecology for refractory cases.
Apply It · Change One Detail
APPLY IT
A 28-year-old woman presents with thin, gray-white vaginal discharge with a fishy odor, worse after intercourse. Vaginal pH is 5.2. Wet prep shows clue cells (>20% of epithelial cells). Whiff test is positive. This is bacterial vaginosis — 3 of 4 Amsel criteria are met. Treat with metronidazole 500 mg PO BID for 7 days or metronidazole vaginal gel. Partner treatment is not recommended. Counsel that recurrence is common.
CHANGE ONE DETAIL
Change one detail — the same patient has yellow-green frothy discharge, vaginal pH of 5.8, and motile organisms on wet prep. This is trichomoniasis — an STI. Treat with metronidazole 500 mg BID for 7 days (preferred over single dose). Test for other STIs. Treat and test all sexual partners. Rescreen at 3 months — reinfection is common.
Bottom Line
Distinguish BV, VVC, and trichomoniasis by pH, wet prep, and clinical features before treating. BV: thin discharge, fishy odor, clue cells, pH >4.5. VVC: thick white discharge, pruritus, yeast on KOH, normal pH. Trichomoniasis: frothy discharge, motile trichomonads, pH >4.5 — treat partners.
EVIDENCE & REFERENCES
- Workowski KA, et al. Sexually Transmitted Infections Treatment Guidelines, 2021. MMWR Recomm Rep. 2021;70(4):1-187. doi:10.15585/mmwr.rr7004a1
- Sobel JD. Vulvovaginal candidosis. Lancet. 2007;369(9577):1961-1971. doi:10.1016/S0140-6736(07)60917-9
- Hillier SL, et al. Bacterial vaginosis. N Engl J Med. 2023;388(19):1795-1806. doi:10.1056/NEJMra2304523