Investigate a patient presenting with vaginal discharge and ulcers

Clinical overview

Vaginal discharge and genital ulcers are two of the most common presentations to South African primary care and to gynaecology outpatients. They are also the entry points to South Africa's syndromic STI management approach, which has been a cornerstone of public health for decades. The registrar must be able to (1) apply the syndromic approach with appropriate algorithmic confidence; (2) know when to depart from it (atypical presentations, complications, treatment failures, immunocompromise); (3) interpret common microbiological tests; (4) integrate STI management with HIV care and partner notification.

Core knowledge

Syndromic approach — South African framework

The SA NDoH STI Management Guidelines use syndromes (clusters of symptoms) to guide empirical treatment without waiting for laboratory confirmation. This is necessary in high-burden, resource-limited settings where same-day treatment reduces transmission and morbidity.

The main syndromes:

1. Vaginal discharge syndrome (VDS) — abnormal vaginal discharge ± itch, dysuria, dyspareunia.
2. Lower abdominal pain syndrome (LAP) — see Acute pelvic infection.
3. Genital ulcer syndrome (GUS) — ulceration of the genital area.
4. Inguinal bubo — inguinal lymphadenopathy.

Each has an algorithm with empirical antibiotic combination treating the likeliest pathogens.

Causes of vaginal discharge

Tap to enlarge Typical visual patterns for BV, Candida, trichomoniasis, and mucopurulent cervicitis.

Physiological:

• Normal vaginal secretions (cyclical changes, increased mid-cycle and pre-menstrual, pregnancy).
• White, non-odorous, no associated symptoms.

Infective:

• Bacterial vaginosis (BV): thin grey-white discharge, fishy odour (especially after intercourse), pH > 4.5, clue cells, positive whiff test. Caused by overgrowth of anaerobes (Gardnerella vaginalis, Atopobium, Mobiluncus) replacing lactobacilli.
• Candidiasis: thick white "cottage cheese," intense itch, vulval erythema, normal pH. See Candidiasis.
• Trichomoniasis: frothy yellow-green discharge, strawberry cervix, intense itch, dysuria. Trichomonas vaginalis — protozoan, sexually transmitted.
• Cervicitis (chlamydia, gonorrhoea): mucopurulent endocervical discharge, contact bleeding, often co-existing with vaginitis. See STI pathology.
• Mycoplasma genitalium: cervicitis; emerging recognition; PCR diagnosis; treatment increasingly difficult due to macrolide resistance.

Non-infective:

• Atrophic vaginitis (postmenopausal).
• Foreign body (forgotten tampon — classic causes of foul discharge).
• Allergic/irritant contact vulvitis.
• Cervical polyps, ectropion.
• Malignancy (especially in postmenopausal bleeding/discharge — exclude endometrial or cervical cancer).
• Fistula — vesicovaginal or rectovaginal (see Gynaecological fistulas).