Abnormal vaginal discharge

Abnormal vaginal discharge is a change in the amount, colour, consistency or odour of vaginal secretions, with or without itch, soreness, dysuria, dyspareunia or bleeding. Physiological discharge is clear to white and mucoid, varies with the menstrual cycle, and the vagina is lactobacillus dominated with a pH of 3.8 to 4.5.

Epidemiology. Bacterial vaginosis is the commonest cause in women of reproductive age, affecting roughly one in four in many settings. Up to three quarters of women have vulvovaginal candidiasis at least once. Trichomoniasis, gonorrhoea, chlamydia and Mycoplasma genitalium are sexually transmitted.

Classification by anatomy. Vaginitis, cervicitis, upper genital tract infection (pelvic inflammatory disease), or discharge from a non infective lesion or fistula.

Classification by character.

• Thin grey and offensive: bacterial vaginosis.
• Thick white and curdy: candidiasis.
• Frothy yellow green: trichomoniasis.
• Mucopurulent: cervicitis.
• Watery: atrophy, tubal or cervical neoplasia, amniotic fluid, fistula.
• Blood stained or brown: neoplasia, polyp, ectropion, retained foreign body.

Classification by group. Prepubertal, reproductive age, pregnancy and postmenopausal.

Mechanisms. Loss of lactobacilli and a rising pH allow anaerobic overgrowth in bacterial vaginosis. Candida overgrowth follows high oestrogen, antibiotics, diabetes or immunosuppression. Low oestrogen thins the epithelium and raises pH in atrophic vaginitis.

History.

• Onset, duration, colour, odour, amount, itch, soreness, dysuria, dyspareunia.
• Intermenstrual or postcoital bleeding, pelvic pain, fever.
• Cycle timing, last menstrual period, possibility of pregnancy.
• Contraception (intrauterine device, retained tampon or condom), sexual history (new partner, number of partners, condom use, partner symptoms), previous sexually transmitted infections.
• Recent antibiotics, douching, hygiene products, diabetes, HIV, immunosuppression.
• Cervical screening status, menopause and hormone therapy, previous episodes and treatment.

Examination.

• Abdominal tenderness. Vulva: erythema, fissures, ulcers, warts.
• Speculum: discharge character and source, cervical mucopurulent discharge, friability, ectropion, polyp, ulcer or mass, strawberry cervix, foreign body.
• Bimanual: cervical motion, uterine or adnexal tenderness, adnexal mass.
• Vaginal pH and sample collection.
• Pregnancy: sterile speculum to look for pooling of fluid; no digital examination when rupture of membranes is suspected.
• Prepubertal child: external inspection only, assess for foreign body and safeguarding.

Red flags.

• Lower abdominal pain, fever, cervical motion tenderness (pelvic inflammatory disease).
• Fluid leakage or contractions in pregnancy.
• Postmenopausal, intermenstrual or postcoital bleeding with discharge (cervical or endometrial cancer).
• Offensive discharge with fever, rash or hypotension (retained tampon, toxic shock).
• Continuous urinary leakage after obstetric or pelvic surgery (fistula).
• Discharge in a child. Immunosuppression. Recurrent treatment failure.

Infective.

• Bacterial vaginosis, vulvovaginal candidiasis, trichomoniasis.
• Cervicitis from Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, herpes simplex.
• Pelvic inflammatory disease, aerobic vaginitis, desquamative inflammatory vaginitis, toxic shock syndrome.
• Genital schistosomiasis in endemic regions, genital tuberculosis.

Non infective.

• Physiological (ovulation, pregnancy, hormonal contraception), mucus plug and lochia.
• Retained foreign body (tampon, condom, pessary), intrauterine device.
• Atrophic vaginitis (genitourinary syndrome of menopause).
• Allergic or irritant vaginitis (douches, spermicide, latex).
• Cervical ectropion and polyp, cervical, endometrial, vaginal and vulval cancer.
• Vesicovaginal and rectovaginal fistula (obstructed labour, pelvic surgery, radiation), prolapse with ulceration.
• Ruptured membranes (amniotic fluid).

Children. Foreign body, threadworm, nonspecific vulvovaginitis, group A streptococcal and Shigella vaginitis, urethral prolapse, sexual abuse.

1. Pregnancy test. Speculum and bimanual examination. Check vaginal pH.
2. Saline and KOH wet mount: clue cells, motile trichomonads, yeast and hyphae, whiff test. Gram stain with Nugent score (0 to 3 normal, 4 to 6 intermediate, 7 to 10 bacterial vaginosis). Amsel criteria: 3 of 4 (thin homogeneous discharge, pH over 4.5, positive whiff test, clue cells).
3. Nucleic acid amplification tests (vaginal, endocervical or first void urine) for chlamydia, gonorrhoea and trichomonas, which is far more sensitive than wet mount (about 50% to 60%). Test for Mycoplasma genitalium in persistent cervicitis or pelvic inflammatory disease.
4. Culture for Candida when recurrent or after treatment failure, to identify non albicans species.
5. HIV, syphilis and hepatitis B serology. Cervical screening if due.
6. Pelvic ultrasound for pain or mass. Colposcopy and biopsy for suspicious cervical lesions. Endometrial sampling for abnormal bleeding.
7. Fistula: methylene blue tampon test, cystoscopy, CT urogram.
8. Suspected ruptured membranes: nitrazine (pH over 6.5), ferning, and an immunoassay for placental alpha microglobulin or insulin-like growth factor binding protein 1.

Limits. Candida colonises 10% to 20% of asymptomatic women; do not treat without symptoms. Bacterial vaginosis can be asymptomatic. Wet mount and speculum findings can be misleading, so confirm with nucleic acid tests.

General. Avoid douching and perfumed products. Treat partners in sexually transmitted infection. Offer contraception and screening.

Bacterial vaginosis. Metronidazole 400 mg orally twice daily for 5 to 7 days, or metronidazole 0.75% gel 5 g intravaginally once daily for 5 days, or clindamycin 2% cream 5 g intravaginally nightly for 7 days (weakens latex condoms). Avoid alcohol during and for 48 hours after metronidazole. Recurrent episodes (3 or more in 12 months): metronidazole 400 mg twice daily for 7 days then metronidazole gel twice weekly for 4 to 6 months. Metronidazole is acceptable in pregnancy.

Vulvovaginal candidiasis. Clotrimazole 500 mg pessary once, or fluconazole 150 mg orally once. Severe disease: fluconazole 150 mg repeated after 72 hours. Recurrent: fluconazole 150 mg every 72 hours for three doses then weekly for 6 months. Pregnancy: clotrimazole 100 mg pessary nightly for 7 days; fluconazole is contraindicated. Non albicans species: specialist care, for example boric acid 600 mg intravaginally daily for 14 days (never swallowed, not in pregnancy).

Trichomoniasis. Metronidazole 500 mg orally twice daily for 7 days. Treat partners and abstain until treatment is complete. Retest at 3 months.

Cervicitis. Doxycycline 100 mg orally twice daily for 7 days; add ceftriaxone 1 g intramuscularly once when gonorrhoea is likely or proven (500 mg in some regimens). In pregnancy use azithromycin 1 g orally once. Partner notification and test of cure in pregnancy.

Pelvic inflammatory disease.

• Outpatient: ceftriaxone 1 g intramuscularly once, plus doxycycline 100 mg orally twice daily for 14 days, plus metronidazole 400 mg orally twice daily for 14 days.
• Inpatient: ceftriaxone 1 to 2 g intravenously daily, plus doxycycline 100 mg twice daily, plus metronidazole 500 mg intravenously every 8 hours. Continue for 24 hours after clinical improvement then complete 14 days orally.

Other causes.

• Atrophic vaginitis: oestradiol 10 micrograms vaginal tablet daily for 2 weeks then twice weekly, or oestriol 0.5 mg cream.
• Foreign body: remove, then assess for toxic shock and infection.
• Suspected cancer: urgent colposcopy or gynaecological oncology referral.
• Fistula: urgent referral. A small fresh fistula may close with continuous bladder drainage for 4 to 6 weeks; otherwise surgical repair.
• Suspected ruptured membranes: urgent obstetric assessment, no digital examination.
• Children: paediatric assessment with safeguarding enquiry.

Monitoring. Review at 2 to 4 weeks for persistent symptoms. Repeat testing after treatment of trichomoniasis (retest at 3 months) and gonorrhoea.

Referral and escalation. Gynaecology or genitourinary medicine for recurrent episodes, treatment failure, atypical findings, suspected neoplasia or fistula. Obstetric services for any pregnancy complication.

Admission. Severe pelvic inflammatory disease (high fever, vomiting, tubo-ovarian abscess, pregnancy, failed oral treatment at 72 hours), toxic shock, ruptured membranes or preterm labour, haemodynamic instability.

Special groups. Pregnancy: bacterial vaginosis is treated with metronidazole 400 mg orally twice daily for 5 to 7 days and candidiasis with clotrimazole 100 mg pessary nightly for 7 days (fluconazole is contraindicated); screen for sexually transmitted infection. Postmenopause: look for atrophy but exclude cancer if bleeding. Diabetes and HIV: control glucose, expect recurrent candidiasis. Breastfeeding: metronidazole single doses are preferred, otherwise a short interruption of feeding is usual.