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:
- Vaginal discharge syndrome (VDS) — abnormal vaginal discharge ± itch, dysuria, dyspareunia.
- Lower abdominal pain syndrome (LAP) — see acute-pelvic-infection.
- Genital ulcer syndrome (GUS) — ulceration of the genital area.
- Inguinal bubo — inguinal lymphadenopathy.
Each has an algorithm with empirical antibiotic combination treating the likeliest pathogens.
Causes of vaginal discharge
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).
Causes of genital ulcers
Sexually transmitted:
- Herpes simplex virus (HSV-1, HSV-2): multiple, painful, vesicular → ulcerated; prodrome (tingling); inguinal lymphadenopathy with primary; recurrent episodes.
- Syphilis (Treponema pallidum): primary chancre — painless, indurated, single (typically), regional lymphadenopathy. Secondary syphilis: condylomata lata, mucous patches.
- Chancroid (Haemophilus ducreyi): painful, ragged-edged, multiple, soft (non-indurated), tender inguinal nodes.
- Lymphogranuloma venereum (LGV — Chlamydia trachomatis L1-3 serotypes): small transient ulcer, then prominent inguinal/femoral lymphadenopathy ("groove sign"); proctitis if anal exposure.
- Granuloma inguinale (donovanosis — Klebsiella granulomatis): rare; beefy-red painless ulcers; tropical climates.
Non-STI:
- Aphthous ulcers — vulval aphthosis (Behçet's-like), idiopathic.
- Behçet's disease: recurrent oral + genital ulcers, ocular and systemic involvement.
- Crohn's disease: vulval involvement uncommon.
- Trauma — sexual or otherwise; FGC.
- Malignancy: vulval cancer often presents as a persistent ulcer.
- Drug eruption: fixed drug eruption may involve genital mucosa.
Examination
- Vulva: inspect with good lighting; look for redness, oedema, lesions, ulcers, dermatoses, FGC.
- Speculum: visualise vaginal walls (atrophy, lesions, foreign body), cervix (mucopus, ectropion, polyps, contact bleeding, lesions).
- Bimanual: cervical motion tenderness, uterine size and tenderness, adnexal mass.
- Inguinal lymph nodes: tender (HSV, chancroid), non-tender firm (syphilis).
- Document with diagram.
Investigations
Discharge:
- Wet mount microscopy: clue cells (BV), trichomonads (motile flagellates), candida hyphae/spores, WBCs.
- pH and whiff test: pH >4.5 + positive whiff (fishy odour with KOH) → BV.
- Endocervical swab for PCR: chlamydia, gonorrhoea, Mycoplasma genitalium, trichomonas.
- Culture: gonorrhoea (for antibiotic sensitivity given resistance).
- Vaginal swab Gram stain: Amsel/Nugent criteria for BV.
Ulcers:
- HSV PCR: from base of fresh ulcer; gold standard.
- Syphilis serology: RPR/VDRL (non-treponemal) + TPHA/EIA (treponemal); dark-field microscopy of chancre material if available.
- HIV test: always.
- Bacterial culture: chancroid (special media — Mueller-Hinton with vancomycin); difficult to grow.
- Biopsy: for persistent unexplained ulcers (rule out malignancy, granulomatous disease).
Diagnostic criteria for BV (Amsel criteria, ≥3 of 4)
- Thin homogeneous grey discharge.
- pH >4.5.
- Positive whiff test (fishy odour with KOH).
- Clue cells on microscopy (≥20%).
Or Nugent score on Gram stain: 7–10 = BV.
Assessment
History
- Discharge: amount, colour, consistency, odour, duration, relationship to cycle.
- Ulcers: number, location, pain, duration, recurrence, prodrome.
- Sexual history: new/multiple partners, condom use, partner symptoms, sexual practices.
- Itch, dysuria, dyspareunia, abnormal bleeding.
- Systemic symptoms: fever, malaise, rash, joint pain, mouth ulcers (Behçet's, secondary syphilis).
- Pregnancy possibility.
- HIV status.
- Previous STIs, treatment history.
- Allergies, medications.
Examination — as above
Management
Vaginal discharge syndromic management (SA NDoH)
Empirical treatment for VDS:
- Ceftriaxone 500 mg IM single dose (cover gonorrhoea — dose raised from 250 mg to 500 mg per SAHCS 2022 / CDC 2021; local resistance to oral options high).
- Doxycycline 100 mg PO 12-hourly × 7 days (cover chlamydia).
- Metronidazole 2 g PO single dose (cover BV and trichomonas).
- ± Antifungal if candida suspected: clotrimazole pessary 500 mg single dose, or fluconazole 150 mg PO.
Modify based on findings:
- Pure candidiasis: clotrimazole or fluconazole alone.
- Pure BV: metronidazole.
- Pure trichomonas: metronidazole 2 g stat (treat partner).
- Mucopurulent cervicitis: full cervicitis treatment.
Partner notification: mandatory; treat partner empirically with same antibiotics.
Genital ulcer syndromic management (SA NDoH)
Cover HSV + syphilis simultaneously, since clinical distinction is unreliable:
- Aciclovir 400 mg PO 8-hourly × 7 days (HSV).
- Benzathine penicillin 2.4 MU IM single dose (syphilis); doxycycline 100 mg 12-hourly × 14 days if penicillin allergic.
- ± Azithromycin 1 g PO stat (covers chancroid and LGV).
Modify based on lab findings:
- HSV PCR positive: continue aciclovir; consider suppressive therapy if frequent recurrences (≥6/year).
- Syphilis confirmed: complete treatment per stage (primary/secondary: single dose; latent >1 year or unknown: 3 weekly doses).
- HSV resistant to aciclovir (rare; HIV with chronic ulcers): foscarnet IV (specialist).
HIV testing
Always offered with any STI presentation. SA practice: opt-out approach.
Partner notification
Statutory in SA for syphilis and HIV. Encouraged for all STIs. Provide contact slip; partner treated empirically.
Notification
Some STIs (syphilis, chancroid, gonorrhoea, donovanosis) are notifiable to the National Institute for Communicable Diseases (NICD). Submit per local protocol.
Special situations
Pregnancy:
- Doxycycline contraindicated → use azithromycin 1 g PO stat for chlamydia, erythromycin 500 mg QID × 7 days for cervicitis.
- Aciclovir safe in pregnancy.
- Treat syphilis adequately to prevent congenital syphilis — penicillin desensitisation if allergic.
- Trichomonas in pregnancy: metronidazole 2 g stat (formerly considered unsafe in first trimester, now considered safe per WHO).
HIV co-infection:
- More severe and atypical presentations.
- Longer treatment courses for severe HSV.
- Treatment failure more common — confirm cure and re-screen.
Recurrent HSV:
- Episodic treatment (early in flare).
- Suppressive treatment if ≥6 episodes/year: aciclovir 400 mg PO 12-hourly daily.
- Reduces transmission to partner.
Atypical or unresolving ulcer:
- Biopsy — rule out malignancy, granulomatous disease, Behçet's.
Foreign body:
- Removal under analgesia/anaesthesia.
- Treat any associated infection.
- Counsel about prevention (especially adolescents).
Red flags / pitfalls
- Treating without HIV testing — every STI is an opportunity.
- Inadequate partner notification — re-infection and ongoing transmission.
- Doxycycline in pregnancy — substitute with azithromycin/erythromycin.
- Missing penicillin for syphilis in pregnancy — desensitise; penicillin only proven prevention of congenital syphilis.
- Treating "thrush" without examination — miss other diagnoses.
- Persistent ulcer dismissed as HSV — biopsy if doesn't heal.
- Postmenopausal discharge ignored — exclude endometrial cancer.
- Foul discharge in young woman — exclude retained foreign body.
- Treating gonorrhoea with single oral agent — SA resistance to oral cephalosporins/quinolones — use ceftriaxone IM.
- Forgetting to screen for other STIs when one is found.
- Mycoplasma genitalium not considered — increasingly recognised; PCR; treatment difficult.
Evidence anchors
- South African National Department of Health STI Management Guidelines (latest edition).
- South African NDoH Standard Treatment Guidelines and Essential Medicines List.
- WHO Sexually Transmitted Infections Treatment Guidelines.
- CDC STI Treatment Guidelines (2021).
- BASHH UK National Guidelines for the management of STIs.
- Amsel R, et al. Nonspecific vaginitis: diagnostic criteria. Am J Med 1983 (foundational BV diagnostic criteria).
- Nugent RP, et al. Reliability of diagnosing bacterial vaginosis is improved by a standardized method of gram stain interpretation. J Clin Microbiol 1991.
- South African HIV Clinicians Society Adult ART Guidelines (2023).