What are the differential diagnoses for vaginal pruritus and the recommended first‑line treatments?

Vaginal Itching: Diagnosis and Treatment

For vaginal itching, you should first obtain microscopic confirmation with a wet-mount preparation using 10% KOH and check vaginal pH before starting treatment, then treat with either a single 150 mg oral dose of fluconazole or short-course topical azole therapy (1-7 days) for uncomplicated vulvovaginal candidiasis, which achieves >90% response rates. 1

Differential Diagnoses

The most common causes of vaginal pruritus when a cause is identified include:

• Vulvovaginal candidiasis (VVC): 20-25% of cases, characterized by pruritus, erythema, and white discharge 2
• Bacterial vaginosis: 40-50% of cases, though itching is less prominent than odor 2
• Trichomoniasis: 15-20% of cases 2
• Noninfectious causes: 5-10% of cases, including atrophic vaginitis (especially in postmenopausal women), irritant/allergic reactions, and inflammatory vaginitis 2, 3

Diagnostic Approach

Obtain microscopic confirmation before treating—do not assume the diagnosis based on symptoms alone. 1

• Check vaginal pH: Normal pH (≤4.5) suggests candidiasis; pH >4.5 indicates bacterial vaginosis or trichomoniasis 1
• Perform wet-mount microscopy: Use 10% KOH preparation to visualize yeast or pseudohyphae for candidiasis diagnosis 1, 4
• Look for specific findings: Candida vaginitis shows yeasts or pseudohyphae on microscopy, with pruritus and erythema in the vulvovaginal area 4

Critical pitfall: Self-diagnosis is unreliable—approximately 10-20% of women harbor Candida without symptoms, so culture positivity alone without symptoms does not warrant treatment 4

First-Line Treatment for Uncomplicated VVC

For uncomplicated vulvovaginal candidiasis, use either oral or topical azole therapy—both achieve 80-90% cure rates. 4, 1

Oral Option (Most Convenient):

• Fluconazole 150 mg oral tablet as a single dose 4, 1

Topical Options (Multiple Effective Regimens):

• Clotrimazole 1% cream 5g intravaginally for 7-14 days (available OTC) 4
• Miconazole 2% cream 5g intravaginally for 7 days (available OTC) 4
• Terconazole 0.8% cream 5g intravaginally for 3 days 4
• Single-dose options: Tioconazole 6.5% ointment 5g intravaginally as single application 4

Important caveat: Oil-based creams and suppositories may weaken latex condoms and diaphragms 4, 1

Over-the-Counter Self-Treatment

Recommend OTC self-medication ONLY for women previously diagnosed with VVC who have recurrence of identical symptoms. 1, 4

• Available OTC preparations include clotrimazole, miconazole, butoconazole, and tioconazole 1, 4
• Any woman whose symptoms persist after OTC treatment or recur within 2 months should seek medical care 4
• Unnecessary OTC use can delay diagnosis of other conditions with adverse outcomes 4

Recurrent Vulvovaginal Candidiasis (≥4 Episodes/Year)

For recurrent VVC, use a two-phase approach: induction therapy for 10-14 days followed by maintenance therapy with fluconazole 150 mg weekly for 6 months. 1, 4

• Obtain vaginal cultures to identify non-albicans species (C. glabrata found in 10-20% of recurrent cases), which respond less well to conventional therapy 4
• Initial therapy: 7-14 days of topical azole or 150 mg oral fluconazole repeated 3 days later 4

Special Population Considerations

Pregnant Women:

Use ONLY topical azole therapy for 7 days in pregnancy—avoid oral fluconazole due to association with spontaneous abortion and congenital malformations. 1

• Metronidazole 2g single dose is safe for symptomatic trichomoniasis in pregnancy 4

HIV-Positive Patients:

Treatment regimens are identical to HIV-negative women with equivalent response rates. 1, 4

Postmenopausal Women:

Consider genitourinary syndrome of menopause (atrophic vaginitis) and dermatologic causes—start with emollients and topical steroids for at least 2 weeks if asteatotic eczema suspected. 1, 3

• Avoid sedating antihistamines in elderly patients 1

When to Refer or Reconsider Diagnosis

Refer to secondary care if diagnostic doubt exists or primary care management fails to relieve symptoms. 1

• Consider biopsy if diagnosis is uncertain, disease fails to respond to treatment, or neoplastic change is suspected 1
• Remember that VVC can occur concomitantly with STDs—test for all pathogens present 4, 1
• If symptoms persist after treatment, reconsider diagnosis and evaluate for desquamative inflammatory vaginitis, genitourinary syndrome of menopause, or vulvodynia 5

Follow-Up

Patients should return only if symptoms persist or recur within 2 months of initial symptom onset. 4