Chapter 106: Vaginal discharge

Vaginal discharge is a common complaint seen by family physicians, yet it is often difficult to solve, especially if it is recurrent or persistent. Women may complain of an increase in the amount of discharge, a change in the consistency or colour and the presence of an offensive odour. It is important to make a proper diagnosis, to differentiate between normal (physiological) and pathological discharge and to be aware of the considerable variation in secretion of vaginal fluid.

This variation extends to different age groups, with microbial causes less likely in prepubertal girls and the elderly, who more often present with dermatoses and symptoms related to reduced vaginal oestrogen.

The differential diagnoses should include consideration of normal discharge, vaginal candidiasis, bacterial vaginosis (BV), STIs, foreign body, vulval dermatoses, atrophic vaginitis and genital tract malignancy.

A summary of the diagnostic strategy model is presented in TABLE 106.1.

Probability diagnosis

The most common causes of vaginal discharge are physiological discharge, vulovaginal candidiasis and bacterial vaginosis.

Physiological discharge

Normal physiological discharge is usually milky-white or clear mucoid and originates from a combination of the following sources:

• cervical mucus (secretions from cervical glands)

• vaginal secretion (transudate through vaginal mucosa)

• vaginal squamous epithelial cells (desquamation)

• cervical columnar epithelial cells

• resident commensal bacteria

The predominant bacterial flora are lactobacilli, which produce lactic acid from glucose derived from the epithelial cells. The lactic acid keeps the vaginal pH acidic (<4.7). Other commensal bacteria include staphylococci, diphtheroids and streptococci.

With physiological discharge there is usually no odour or pruritus.

In addition, the egg-white discharge accompanying ovulation may be noted. Normal discharge usually shows on underwear by the end of the day. Clear or white, it oxidises to a yellow or brown on contact with air. It is often increased in pregnancy and during sexual arousal. Women using the combined oral contraceptive pill may notice less discharge.

Management is largely based on reassurance and explanation.

Important causative organisms

Vulovaginal candidiasis is caused by an overgrowth of yeasts, usually Candida albicans, or less commonly other species such as Candida glabrata, Candida tropicalis and Candida krusei.¹ Bacterial vaginosis is a polymicrobial condition characterised by changes in the normal vaginal flora, with a reduction in key Lactobacillus species and high concentrations of anaerobic bacteria such as Gardnerella vaginalis.² Trichomonas vaginalis is of high prevalence in some remote Aboriginal and Torres Strait Islander communities. The comparable features are outlined in TABLE 106.2.

Serious disorders not to be missed

The ‘not to be missed’ group includes cancer of the vagina, cervix or uterus and STIs, including PID caused by Chlamydia trachomatis, Neisseria gonorrhoeae and Mycoplasma genitalium. Vaginal discharge is the most common presenting symptom of these STIs in women; however, they are commonly asymptomatic. Benign and malignant neoplasia anywhere in the genital tract may produce a discharge. Usually it is watery and pink or blood-stained.

Inspection should include vigilance for fistulas that may be associated with malignancy, inflammation or post-irradiation.

Pitfalls

It is common to overlook contact dermatitis caused by topical preparations. Apart from the vaginal tampon, which may be retained (knowingly or otherwise), there is a variety of preparations that can induce a sensitivity reaction. These include deodorant soaps and sprays and spermicidal creams. Ironically, the various preparations used to treat the vaginitis may cause a chemical reaction.

Seven masquerades checklist

Of this group, diabetes mellitus leading to recurrent ‘thrush’ and drugs causing a local sensitivity have to be considered (see TABLE 106.1).

Psychogenic considerations

This question needs to be answered, especially if the discharge is normal. The problem could be related to sexual dysfunction or it may reflect a problematic relationship, and the issue may need to be explored diplomatically. Vaginal discharge is an embarrassing problem for the patient and any discussion needs to be handled thoroughly and sensitively.

History

The history is important and should include:

• nature of discharge: colour, odour, quantity

• onset and duration, relation to menstrual cycle

• irritation or itch and location

• associated dyspareunia

• pelvic or abdominal pain

• sexual history: STI risk factors, previous STIs

• use of chemicals, such as soaps, deodorants, pessaries and douches

• pregnancy possibility

• drug therapy (e.g. antibiotics, oral or topical corticosteroids)

• associated medical conditions (e.g. diabetes)

Examination

Inspection in good light includes viewing the vulva, introitus, urethra, vagina and cervix. Check the vulva for erythema, excoriation, lichenification, linear fissures and atrophic changes. Look for the discharge and specific problems such as polyps, warts, prolapses or fistulas. A mucopurulent discharge appearing from the endocervix may be the clue to an STI such as Chlamydia or gonorrhoea. Consider bimanual pelvic examination according to history, checking for adnexal, uterine and cervical motion tenderness.

Pitfalls to keep in mind include:

• A retained tampon may be missed in the posterior fornix, so the speculum should slide directly along the posterior wall of the vagina.

• Candida infection may not show the characteristic discharge.

• The ‘strawberry vagina’ of Trichomonas is uncommon and bubbles may not be seen.

Acetic acid 2% may be useful in removing discharge and mucus to enable a clearer view of the cervix and vaginal walls.

Investigations¹

• High vaginal swab for microscopy and culture

  • – for Candida species, bacterial vaginosis

• High vaginal swab for STIs Chlamydia trichomatis, N. gonorrhoea and Mycoplasma genitalium NAAT (i.e. PCR)

  • – consider Trichmonas vaginalis NAAT if patient from endemic region

• pH test of vaginal discharge

  • – use paper with a narrow range of pH 4–7

  • – result can be altered by semen, blood, cervical secretions and lubricating jelly

• Amine or ‘whiff’ test for BV: add a drop of 10% KOH to vaginal secretions smeared on glass slide, positive with release of fishy odour

• Wet-film microscopy of a drop of vaginal secretions (if microscope available)

• Consider PCR for herpes simplex virus if no other explanation

Preparation of a wet film

To make a wet film preparation³ (see FIG. 106.1), place one drop of normal saline (preferably warm) on one end of an ordinary slide and one drop of 10% KOH on the other half of the slide. A sample of the discharge needs to be taken with a swab stick, either directly from the posterior fornix of the vagina or from discharge that has collected on the posterior blade of the speculum during the vaginal examination. A small amount of the discharge is mixed with both the normal saline drop and the KOH drop. A cover slip is placed over each preparation. The slide is examined under low power to get an overall impression, and under high power to determine the presence of lactobacilli, polymorphs, trichomonads, spores, clue cells and hyphae. A summary of various findings on wet film examination is presented in TABLE 106.3. Lactobacilli are long, thin Gram-positive rods; clue cells are vaginal epithelial cells that have bacteria attached so that the cytoplasm appears granular and often the entire border is obscured. They are a feature of bacterial vaginosis. Trichomonads are about the same size as polymorphs; to distinguish between the two, one needs to see the movement of the trichomonad and the beating of its flagella under high power of the microscope. Warming the slide will often precipitate movement.

Refer to FIGURE 106.2.

Most newborn girls have some mucoid white vaginal discharge. This is normal and usually disappears by 3 months of age. From 3 months of age to puberty, vaginal discharge is usually minimal. Vulvovaginitis is the most common gynaecological condition of childhood, the causal factors being the normal thin mucosa of the prepubescent state, moisture and irritants.

If discharge is profuse or offensive, take an intraoital swab, which may reveal organisms such as group A Streptococcus, Haemophilus and Gardnerella. An appropriate antibiotic may help in this instance. Candida infection is unusual in children from 2 years until puberty.

Sexual abuse occasionally presents as vulvovaginitis.

Vaginal discharge in the elderly is most commonly due to atrophic vaginitis. Other causes include foreign bodies, bacterial vaginosis and neoplasia. It is important to exclude malignancy of the uterus, cervix and vagina in the older patient.

Vulvovaginal candidiasis does not occur in healthy, non-diabetic women who have not been taking antibiotics and lack oestrogen. However, it can occur in women taking menopause hormone therapy (MHT) and topical oestrogen. In this case, stop oestrogen treatment and treat for chronic vulvovaginal candidiasis until symptoms resolve. It may then be appropriate to recommence oestrogen therapy at a lower dose or continue the usual dose, but with intermittent treatment for candida.⁵

Atrophic vaginitis

In the absence of oestrogen stimulation, the vaginal and vulval tissues begin to shrink and become thin and dry. This renders the vagina more susceptible to bacterial attack because of the loss of vaginal acidity. Rarely, a severe attack can occur with a very haemorrhagic vagina and heavy discharge:

• yellowish, non-offensive discharge

• tenderness and dyspareunia

• spotting or bleeding with coitus

• the vagina may be reddened with superficial haemorrhagic areas

Treatment

• oestrogen cream or pessary (e.g. Ovestin, Vagifem) daily at bedtime for 2–3 weeks, then once or twice weekly

• or

• zinc and castor oil soothing cream

• Note: perform a careful speculum examination.

Vulvovaginal candidiasis

Candida species are commensal organisms of the gastrointestinal and genital tract. Most cases of candidal vulvovaginitis are infrequent episodes resulting from sporadic increases in vaginal candida. It occurs when the vagina is exposed to oestrogen and is especially common in women aged 20–30 years and during pregnancy. It is not sexually transmissible, although sexual intercourse may be a trigger. Recurrent candidal vulvovaginitis is defined as four or more acute episodes per year.

Some 10–20% of women may be colonised with candida without signs or symptoms. Treatment is not indicated for these women.

Clinical features

• Intense vaginal and vulval pruritus

• Vulval soreness

• Vulval fissures

• Vulvovaginal erythema (brick red)

• Vaginal excoriation and oedema

• White, curd-like discharge (see FIG. 106.3)

• Superficial dyspareunia

• Dysuria

Factors predisposing to vaginal candidiasis⁶

Endogenous

• Diabetes mellitus

• Pregnancy

• Immune deficiency, e.g. HIV

Exogenous

• Oral contraceptives (but cessation of the OCP does not usually improve candidiasis)

• MHT or topical oestrogen

• Antibiotics

• Corticosteroid therapy

• Immunosuppressants

• Orogenital/anogenital intercourse

• IUCD

• Tight-fitting jeans

• Nylon underwear

• Wet bathing suit

Treatment^5,7

Before starting treatment, take a swab to confirm the diagnosis and determine the species of Candida. For the first attack of candidiasis, it is appropriate to select one of the range of vaginal azole therapies (clotrimazole, miconazole) for 1–7 days, depending on strength. There appears to be no significant difference between azoles. Nystatin is best reserved for recurrent cases or if there is local reaction to the azoles.

Creams can be applied to the vulva if there are vulval symptoms. Combining azole therapy with a topical corticosteroid such as 1% hydrocortisone may also be useful.

Gentian violet (0.5% aqueous solution) is useful for rapid relief, if available.

Recommended initial regimen⁵

• clotrimazole 1%, 2% or 10% vaginal cream, 1 applicatorful intravaginally, at bedtime for 6 nights if 1%, 3 nights if 2% or once only if 10%

• or

• miconazole 2% vaginal cream, 1 applicatorful intravaginally, at bedtime for 7 nights

• or

• clotrimazole 100 mg or 500 mg pessary intravaginally, at bedtime for 6 nights if 100 mg, once only if 500 mg

An alternative regimen, especially for recurrent infections:

• nystatin vaginal cream (100 000 U per 5 g), 1 applicatorful intravaginally, at bedtime daily for 14 nights

If the patient does not tolerate vaginal therapy or prefers oral therapy, use fluconazole 150 mg (o) as a single dose

Chronic vulvovaginal candidiasis⁸

Patients with chronic vulvovaginal candidiasis are a less well-recognised and -managed group. The pathogenesis is unknown but may relate to an exaggerated immunological response to candida. Viewing the condition as a hypersensitivity reaction to the presence of candida, rather than infection, helps understanding and guides treatment. It may start at any age from menarche onwards and ceases at menopause provided MHT is not used.

The most common complaint is chronic itch with dyspareunia and pain. Vaginal discharge is common but may be absent and the typical cottage cheese exudate is not seen. Symptoms are often worse in the premenstrual week and improve during menses. Initial response to azole treatment is common but there is gradual resistance to topical therapy. Almost 95% of cases are caused by C. albicans.

When taking the swab, a low vaginal swab usually has a higher yield than a high vaginal swab. False negatives are common.

Treatment⁵

• fluconazole 50 mg (o) once daily

• or

• itraconazole 100 mg (o) once daily

The time to achieve remission varies from 2 weeks to 6 months. Review treatment after 3 months. A mild topical steroid is also appropriate to use in addition.

Note: There is no evidence to support routine screening or treatment of asymptomatic partners.¹ If a male partner is symptomatic (usually balanitis in an uncircumcised male), treat with clotrimazole 1% + hydrocortisone 1% topically, 12 hourly until 2 weeks after symptoms resolve.

Candida glabrata⁵

A significant number of cases of vulvovaginal candidiasis are due to non-albicans species of Candida. Candida glabrata is the commonest non-albicans species, which exhibits reduced susceptibility to azoles. In resistant infections, use boric acid 600 mg (in a gelatin capsule) intravaginally at bedtime for 14 days. Do not use in pregnancy.

General advice to patients with vaginal candidiasis^5,9

• Bathe the genital area with water and dry gently but thoroughly after showering or bathing.

• Wear loose-fitting, cotton underwear.

• Avoid wearing pantyhose, tight jeans or tight underwear.

• Do not use vaginal douches, powders or deodorants or take bubble baths.

Trichomonas vaginalis¹⁰

This flagellated protozoan, which is thought to originate in the bowel, infects the vagina, Skene’s ducts and lower urinary tract in women and the lower genitourinary tract in men. It is easily transmitted through sexual intercourse. In Australia, trichomonas is more common in older women and women from regional and remote areas, especially Aboriginal and Torres Strait Islander. If untreated, the infection is cleared more easily in men. NAAT test is available on vaginal swab and first-pass urine.

Clinical features

• Profuse, thin discharge (grey to yellow–green in colour) (see FIG. 106.4)

• Small bubbles may be seen in 20–30%

• Vulval itch

• Malodorous discharge

• Dyspareunia

• Diffuse erythema of cervix and vaginal walls

• Characteristic punctate appearance on cervix

Treatment

• oral metronidazole 2 g as a single dose (preferable) or 400 mg bd for 5 days (if relapse)

• or

• tinidazole 2 g as a single dose

• Sexual partners must be treated simultaneously

• No sexual contact is advised for 7 days after treatment for patient and partner

Bacterial vaginosis

Bacterial vaginosis is a clinical entity of mixed aetiology characterised by the replacement of the normal vaginal microflora (chiefly Lactobacillus) with a mixed flora (referred to as polymicrobial clinical syndrome) consisting of Gardnerella vaginalis, other anaerobes such as Atopobium vaginae, Mobiluncus species and Mycoplasma hominis. This accounts for the alkalinity of the vaginal pH.

Clinical features

• A white or grey, homogenous discharge (see FIG. 106.5)

• Malodorous

• No obvious vulvitis or vaginitis

• Liberates an amine-like, fishy odour on admixture of 10% KOH (the amine whiff test)

• Clue cells on wet preparation

• ± Dyspareunia and dysuria

• ± Pruritus (uncommon)

Note. About 50% of patients are asymptomatic.

Treatment⁵

Refer to TABLE 106.4.

• If symptomatic:

• metronidazole 400 mg (o) bd for 5 days (or 2 g stat)

• or

• 0.75% vaginal gel applied at bedtime for 5 days

Clindamycin 300 mg (o) bd for 7 days or 2% clindamycin cream, 1 applicatorful at bedtime for 7 nights, can be used for resistant infections or during pregnancy. Treating male partners has not been recommended; however, consider screening and treating female sexual partners.²

Group B Streptococcus vaginosis¹¹

Group B Streptococcus (S. agalactiae) is a commensal in up to 30% of healthy humans. It is a problem if detected in pregnant women because of the risk of serious infection in the neonate that is delivered vaginally. Other than in pregnancy, it is generally an incidental finding and should be ignored.

Rarely, Group B Steptococcus produces a symptomatic vulvovaginitis with an irritating discharge. However, other causes of vulvovaginitis are more common and should be considered. Suitable treatment for symptomatic patients includes clindamycin 2% vaginal cream, 1 applicatorful intravaginally at bedtime for 14 nights, and phenoxymethylpenicillin 500 mg orally, bd for 10 days.

Retained vaginal tampon

A retained tampon, which may be impacted and cannot be removed by the patient, is usually associated with an extremely offensive vaginal discharge. Its removal can cause considerable embarrassment to both patient and doctor.

Methods of removal

Using good vision the tampon is seized with a pair of sponge-holding forceps and quickly immersed under water without releasing the forceps. A bowl of water (an old plastic ice-cream container is suitable) is kept as close to the introitus as possible. This results in minimal malodour. The tampon and water are immediately flushed down the toilet if the toilet system can accommodate tampons. An alternative method is to grasp the tampon with a gloved hand and quickly peel the glove over the tampon for disposal.

Tampon toxic shock syndrome: staphylococcal infection

This rare, dramatic condition is caused by the production of staphylococcal exotoxin associated with tampon use for menstrual protection. The syndrome usually begins within 5 days of the onset of the period.

The clinical features include sudden onset fever, vomiting and diarrhoea, muscle aches and pains, skin erythema, hypotension progressing to confusion, stupor and sometimes death.

Management

Active treatment depends on the severity of the illness. Cultures should be taken from the vagina, cervix, perineum and nasopharynx. The patient should be referred to a major centre if ‘shock’ develops. Otherwise the vagina must be emptied, ensuring there is not a forgotten tampon, cleaned with a povidone iodine solution tds for 2 days, and flucloxacillin or vancomycin antibiotics administered.

Prevention

• Good general hygiene with care in handling and inserting the tampons.

• Change the tampon 3–4 times a day.

• Consider using an external pad at night during sleep.

• Evidence of sexual abuse in children (to an experienced sexual assault centre)

• Recurrent, recalcitrant infections

• Presence of cancer or fistula

• Staphylococcal toxic shock syndrome

Hand-out sheets from Murtagh’s Patient Education 7th edition:

• Vaginal thrush

• Vulvovaginal irritation in children