Vaginal Discharge
Vaginal discharge is usually a symptom of the reproductive years, but can occur at any age. It can be influenced by the menstrual cycle, use of ‘the pill’, age, pregnancy and sexual activity. Treatment is often simple, but if it fails, or if there are risk factors for STDs, it is sensible to refer to a GUM clinic.
Differential diagnosis
Common Diagnoses
- Excessive Normal Secretions
- Thrush
- Bacterial Vaginosis (BV)
- Trichomonal Vaginosis (TV)
- Cervicitis (Gonococcus, Chlamydia, Herpes)
Occasional Diagnoses
- Cervical Ectropion
- Cervical Polyp
- Lost Tampon, Ring Pessary or other Foreign Body
- IUCD
- Bartholinitis
- Salpingitis
Rare Diagnoses
- Vulvovaginal Neoplasia
- Cervical or Uterine Neoplasia
- Sloughing Intrauterine Fibroid
- Pyometra
- Pelvic Fistula
Ready reckoner
Key distinguishing features of the most common diagnoses
| Normal | Thrush | BV | TV | Cervicitis | |
|---|---|---|---|---|---|
| Intense Itch | No | Yes | No | Possible | Possible |
| Offensive Smell | No | No | Yes | Yes | Possible |
| Vulval Soreness | No | Yes | No | Yes | Possible |
| Yellow/Green/Grey (Mucopurulent) Discharge | No | No | Yes | Yes | Yes |
| Inflamed Cervix | No | No | No | Yes | Yes |
Possible investigations
Likely: High vaginal swab (HVS).
Possible: Endocervical swab, urethral swab, urine testing for Chlamydia, blood sugar or HbA1c.
Small Print: Other specialist investigations.
- Most GPs would confine themselves to the HVS, endocervical swab and urine test. Those with a special interest might undertake the microscopy themselves.
- HVS is simple and readily detects Candida, BV and TV.
- Wet saline microscopy shows clue cells in BV, motile trichomonads in TV.
- Gram stain of cervical or urethral exudate shows negatively staining diplococci in up to 85% of gonococcal infections.
- Endocervical swab for ELISA is the gold standard for detecting Chlamydia.
- DNA amplification testing of first-catch urine (not MSU) specimens for Chlamydia is noninvasive and relatively acceptable to patients.
- Blood sugar or HbA1c: To detect diabetes in severe or recurrent thrush.
- Specialist investigations might include D&C or hysteroscopy (for possible malignancy) and barium enema (for pelvic fistula).
Top Tips
- It is reasonable to diagnose and treat thrush empirically in a woman with classical symptoms who has had the problem before – many women successfully self-medicate and only attend to obtain their treatment free, via a prescription. But if in any doubt about the diagnosis, examine and investigate as appropriate.
- It is worth investing time with the patient suffering confirmed recurrent thrush – advice supplemented by written patient information may help minimise future problems.
- Make sure you have all the appropriate swabs (HVS, endocervical, urethral) to hand – you never know when you might need them.
- Excessive concern about normal secretions might mask a sexual problem or worry – enquire discreetly about this.
Red Flags
- Recurrent or florid thrush may be a presentation of undiagnosed diabetes mellitus. Ask about thirst, polyuria and tiredness and check a fasting glucose if any suspicion of underlying diabetes, or there is a positive family history of diabetes.
- Vaginal discharge is an uncommon symptom before puberty. Don’t forget the possibilities of abuse or a foreign body.
- Always conduct a full pelvic examination in the post-menopausal woman with vaginal discharge. Malignancy is one of the likeliest causes.
- A florid erosion is likely to be caused by chlamydial cervicitis – take a swab and treat appropriately.
- If you suspect a sexually transmitted disease, refer to the GUM clinic for full assessment and contact tracing. Refer urgently to the GUM clinic or duty gynaecologist if there are systemic flu-like symptoms and fever with pelvic pain and vaginal discharge.