Clinical overview
Vulvovaginal candidiasis (VVC) is one of the most common reasons women self-medicate, present to pharmacists, and arrive at gynaecology clinics. Up to 75% of women will experience at least one episode in their lifetime; ~10% develop recurrent (≥4 episodes per year) disease, the management of which is more nuanced than acute single episodes. The pathology — fungal colonisation transitioning to symptomatic infection in the right immunological and microbial milieu — explains why it is so common and why it recurs.
Core knowledge
Aetiology
- Candida albicans — 80–90% of clinically symptomatic episodes.
- Non-albicans Candida species: C. glabrata, C. krusei, C. parapsilosis, C. tropicalis — more common in recurrent disease, immunocompromise, postmenopausal women, and after antifungal exposure; often more resistant to azoles.
Candida is part of normal gut and sometimes vaginal flora. Symptomatic infection arises when:
- Local immune environment changes (high oestrogen, pregnancy, COC, glucocorticoids, immunosuppression).
- Antibiotic use disrupts protective lactobacilli.
- Glycaemic control deteriorates (diabetes).
- Local barrier disruption (irritants, tight clothing).
- HIV infection with low CD4 — recurrent candidiasis is one of the WHO clinical staging signs.
Pathology
Candida yeast and pseudohyphae adhere to damaged vaginal epithelium while PMNs drive itch, erythema and oedema.
- Yeast-to-hyphal phenotype switch is associated with virulence; hyphal forms invade epithelium.
- Adhesion via candidal adhesins (Als family proteins) to vaginal epithelial cells.
- Epithelial damage, breakdown of barrier, exposure of nerves → itch and burning.
- Inflammatory response with PMN infiltration, oedema, erythema.
- Biofilm formation in chronic/recurrent disease; biofilm enhances antifungal resistance.
Clinical features (correlating pathology to presentation)
- Thick, white, "cottage-cheese" discharge — pseudohyphal mass and shed epithelial cells.
- Intense itch and burning — inflammatory cytokine release and epithelial damage.
- Vulval erythema and oedema — local inflammation.
- Fissures and excoriations — from scratching plus epithelial fragility.
- Vulval dyspareunia, external dysuria — irritation of inflamed vulval skin by intercourse or urine contact.
- Normal vaginal pH (<4.5) — distinguishing feature from BV/trichomonas (pH > 4.5).
Recurrent VVC (RVVC)
- Defined as ≥4 episodes in 12 months.
- Often C. albicans with predisposing factors rather than non-albicans (do not assume resistance).
- Predisposing factors: diabetes, immunosuppression, HIV, exogenous oestrogens, frequent antibiotic use, sexual practices, vaginal douching.
- Investigation: confirm diagnosis with culture (not just microscopy); HbA1c; HIV status if not known; consider rare immunodeficiency in atypical cases.
Special situations
- Pregnancy: more common (high oestrogen, increased vaginal glycogen). Often treatment-resistant. Use topical only; avoid oral fluconazole (especially high-dose; some teratogenicity signal at high cumulative doses).
- Diabetes: more frequent and severe; optimise glycaemic control.
- HIV (CD4 <200): oesophageal candidiasis may co-occur; consider systemic disease.
- Postmenopausal: atypical presentation; lower threshold for atrophic vaginitis as differential.
Assessment
History
- Discharge: amount, consistency, smell (typically odourless).
- Itch, burning, dyspareunia.
- Previous episodes; frequency; previous treatments.
- Antibiotic use, contraceptive method, diabetes, immunosuppression, HIV status.
- Pregnancy possibility.
- Sexual history and partner symptoms (uncommon in male partners but balanitis possible).
Examination
- Vulval erythema, oedema, fissures, scratch marks.
- Speculum: thick white discharge adherent to vaginal walls; vaginal mucosa erythematous; cervix normal (unlike cervicitis).
Investigations
- Wet mount: pseudohyphae, spores (~70% sensitivity in symptomatic women).
- pH < 4.5 (normal); pH ≥ 4.5 suggests alternative diagnosis (BV, trichomonas) — note that mixed infections occur.
- Culture (Sabouraud or chromogenic medium): confirms diagnosis, identifies species, and allows antifungal sensitivity — useful for recurrent or treatment-resistant cases.
- Don't routinely culture in uncomplicated single episodes.
Management
Acute uncomplicated VVC
- Topical: clotrimazole 500 mg pessary single dose, or clotrimazole 100 mg pessary nightly × 6 nights; ± clotrimazole 1% cream for vulval symptoms.
- Oral: fluconazole 150 mg single dose (avoid in pregnancy).
- Cure rate ~90% with either route; choice based on patient preference, pregnancy status, severity.
Severe VVC (intense symptoms)
- Topical clotrimazole 100 mg nightly × 7 nights or fluconazole 150 mg × 2 doses 3 days apart.
Pregnancy
- Topical only — clotrimazole 100 mg pessary nightly × 7 nights, or clotrimazole 500 mg pessary single dose.
- Avoid oral antifungals; fluconazole at high cumulative doses associated with risk; emergency single dose probably safe but topical preferred.
Recurrent VVC
- Confirm diagnosis with culture and species.
- Induction: fluconazole 150 mg every 72 hours × 3 doses, then maintenance.
- Maintenance: fluconazole 150 mg weekly × 6 months.
- ~90% suppressed during therapy; ~50% remain in remission 6 months after stopping.
- Address predisposing factors (glycaemic control, HIV care).
- Treat partner only if symptomatic balanitis.
Non-albicans species (especially C. glabrata)
- Often azole-resistant.
- Boric acid intravaginal capsules 600 mg nightly × 14–21 days (highly effective; specialist prescribing; not for use in pregnancy).
- Topical nystatin 100,000 IU × 14 nights.
- Consult specialist.
General measures
- Avoid douching, scented soaps, tight non-breathable underwear.
- Probiotics — limited evidence; not first-line.
- Treat constitutional symptoms; ensure HIV testing if recurrent.
Red flags / pitfalls
- Repeated empirical antifungal treatment without diagnosis confirmation — biopsy/culture for chronic or recurrent symptoms.
- Missing HIV in recurrent disease.
- Treating "candida" that is actually atrophic vaginitis in postmenopausal women.
- Oral fluconazole in pregnancy — substitute topical.
- Failing to address glycaemic control in diabetes.
- Assuming all recurrent disease is non-albicans-resistance — most is C. albicans with predisposition.
- Not considering coexistent BV or trichomonas — pH > 4.5 should prompt full STI screen.
Evidence anchors
- CDC STI Treatment Guidelines 2021 (Vulvovaginal Candidiasis section).
- BASHH UK National Guideline for the Management of Vulvovaginal Candidiasis (2019).
- South African National Department of Health STI Management Guidelines (latest; SAHCS 2022 STI Guidelines support).
- South African National HIV Guidelines (2023) — recurrent candidiasis as WHO stage 3 marker.
- Sobel JD. Recurrent vulvovaginal candidiasis. Am J Obstet Gynecol — classical reference; recurrent management.
- WHO Classification of Female Genital Tumours and Inflammatory Disease — histology references.
- NICE Clinical Knowledge Summaries — Candida (Female).