The complaint of chronic abnormal vaginal discharge (VD) is a frequent presentation to gynaecologists and women’s health GPs. Many women worry about whether VD is normal and variations typically provoke concerns about STIs, cancer, self-image and sexual confidence. It is important to know what is normal, what is abnormal, and how to make an accurate diagnosis that will lead to correct advice.

The vulval epithelium extends to the hymen. Inflammatory conditions of the vaginal introitus, for example psoriasis, produce desquamation and oedema fluid. This can be mistaken for heavy vaginal discharge.

There are many conditions that affect the vulva and the vagina that can cause an abnormal VD. Although infection is usually considered first, virtually any inflammatory condition may be implicated.

Normal vaginal discharge

Normal VD is a mixture of vaginal wall transudate, cervical mucus, sweat and vulval and vaginal skin squames. This means that VD may be modified by not only vaginal, but also vulval factors.

Normal VD during the menstrual years is clear to white or light yellow in colour. It is cyclical: minimal post-menstrually, very clear and stretchy at mid-cycle and then becoming progressively thicker until the onset of the next period. It is not associated with vulval soreness or itch.

Premenarchal girls have very little VD. After the menopause, VD volume gradually reduces along with falling oestrogen levels and becomes more yellow in colour. Pregnancy makes physiological VD heavier. The combined oral contraceptive pill results in loss of the stretchy appearance of mid-cycle ovulatory VD, but otherwise does not substantially change the nature of VD.

VD is highly variable from woman to woman. It can be very light to very heavy. The age of menarche will effect the age at which adult VD commences. This means that the woman whose periods started at age 17 will have the mentality of an adult by the time her normal VD begins. She may be more likely to be concerned that her physiological VD is abnormal than a woman whose menarche was at age 12.

Characteristics of abnormal vaginal discharge

The following is a list of possible abnormalities of VD:

• Abnormal colour; brown, green, blood-stained (a green VD prior to puberty can be normal)
• Abnormal consistency; thicker, more watery
• Loss of cyclical pattern
• Abnormal smell
• Association with other symptoms; itch, soreness, dyspareunia.

Causes of chronic abnormal vaginal discharge

Causes of abnormal VD are listed in Table 1. Table 2 lists those most likely to be seen in Australian metropolitan practice. Infections are the most common, especially in general practice. These are well recognised and very adequately dealt with elsewhere. The rest of this article discusses the less well-recognised non-infective causes of VD.

Personal hygiene practices

It is important to ask women about their personal habits regarding cleaning, hair removal and deodorising. Some of these habits may trigger or promote abnormal discharge by causing an irritant contact dermatitis. Unless these practices are identified and eliminated, treating the original problem will then be ineffective, with resulting confusion for the clinician and disappointment for the patient.

Enquiry about personal practices can be difficult if the patient is embarrassed. Even when the clinician is able to identify these habits, many patients cannot accept that these might be causing or exacerbating their abnormal discharge.

The use of pads for urinary or faecal incontinence can also cause or exacerbate an abnormal discharge. Some women have allergic contact dermatitis reactions to some brands of pads and this possibility should be investigated. An attempt should be made to reduce the use of pads whenever possible, for example when the patient is at home. Any therapy that might reduce incontinence should of course be  implemented.

Chronic vulvovaginal candidiasis

Patients with acute and recurrent vulvo-vaginal candidiasis are, by definition, normal in between episodes. In contrast, patients with chronic vulvovaginal candidiasis (CVVC) have a continuously symptomatic vulvo-vaginitis that is worst pre-menstrually and improves during the period. CVVC is thought to represent a vaginal mucosal hypersensitivity reaction to the candida organism rather than a chronic infection and this means that vaginal culture may not always be positive. The following validated criteria are used to make the diagnosis.1

Diagnostic: One major + five minor criteria
Presumptive: One major + three to four minor criteria

Major criterion:

• Chronic non-erosive, non-specific vulvovaginitis.

Minor criteria:

• Positive vaginal swab either on presentation or in the past
• Soreness
• Cyclicity
• Dyspareunia
• Previous response to antifungal therapy even if incomplete
• Exacerbation with antibiotics
• Swelling
• Discharge.

Continuous daily treatment with fluconazole 50–100mg for three to six months is usually effective. However, these women are at risk of relapse, especially with the use of antibiotics, and often need ongoing suppressive therapy.

Desquamative inflammatory vaginitis

Desquamative inflammatory vaginitis (DIV) is a non-infective vulvovaginitis with the typical clinical appearance of erythematous glazed and/or petechial patches on the mucosal surface of the labia minora. It is possibly the same entity as Zoon vulvitis and Plasma Cell vulvitis.

Like lichen planus, with which it is often confused, DIV involves the vagina and mucosal surface of the labia minora. However, unlike lichen planus, it does not extend to involve the vulval skin or the oral mucosa and does not produce scarring. The aetiology is not certain, but is possibly a disturbance of normal vaginal homeostasis, leading to a reduction in lactobacilli and commensal overgrowth. There is often a trigger, for example, diarrhoea, antibiotic use or pelvic surgery.2

DIV usually presents with soreness, dyspareunia and VD. The examination shows erythematous patches within the introitus and speculum examination may also show patchy vaginitis. Vaginal culture is negative for pathogens. (Group B streptococcus is often cultured, but may not be clinically relevant in this context.) Rapid improvement occurs with a four-week course of low-dose clindamycin vaginal cream every night. About 50 per cent of women are then cured, but others experience recurrent episodes.

Vulval psoriasis

Psoriasis is not uncommon on the vulva.3 It causes accelerated skin turnover and the resulting squames mix with physiological VD, making it heavy and often malodorous. On external hair-bearing vulval skin, psoriasis is usually easy to recognise. However, when it effects the modified mucous membrane of the labia minora and vaginal introitus, clinical recognition is more difficult, and the resulting itch and soreness can be mistakenly thought to be vaginal.

Psoriasis often also involves perianal and natal cleft skin, and this can help to make the diagnosis, as can a personal or family history of psoriasis. Correctly identifying psoriasis apart from dermatitis is important, as psoriasis is usually a very long-term condition that cannot be cured (unlike many types of dermatitis) and must be managed to give the patient the best chance of a good quality of life.

We recommend a regimen consisting of six weeks of:

• Methylprednisolone fatty ointment applied at night
• Two per cent LPC (coal tar solution) in emulsifying ointment applied in the morning.

Thereafter, topical corticosteroid is ceased and LPC is applied morning and night as maintenance therapy. Topical corticosteroid is used to manage flare ups, which are expected in any chronic skin disease. Refer to a dermatologist in cases that are not straightforward.

Contact vaginitis and vulvitis

History-taking in cases of suspected contact vulvovaginitis can be difficult, firstly because the patient does not always make the association between the use of a certain product and her abnormal VD, but also because of her reluctance to admit to what she has been using. Furthermore, it is not always a product which has caused the vaginitis or vulvitis. Many women over-clean their vulval and vaginal skin, and this either causes or exacerbates the problem.

Clothes are an important cause of vulval dermatitis, particularly lycra, tight jeans and other occlusive garments.

Patients who suffer from hyperhidrosis may develop maceration of the skin, leading to dermatitis, and this coupled with heavy sweating can be mistaken for abnormal VD.

Lichen planus

Even though this is a rare cause of VD, it is important to identify lichen planus because of the devastating scarring that occurs if it is left untreated. Patients typically present with heavy VD and pain, especially with intercourse. On the vulva, lichen planus usually involves the modified mucous membranes and the vaginal mucosa. Although the typical appearance is an erythematous rash with erosions, they are often very subtle and easily missed. Biopsy is frequently unhelpful. Most cases require ultra-potent topical corticosteroids and/or systemic immunosuppressants for adequate control.4 We recommend referral to a specialist if the diagnosis is suspected.

Perceptual issues

Every women’s health practitioner will be familiar with the (often young) woman who presents with the complaint of chronic heavy VD, but with no other abnormal symptoms, and with an entirely normal examination and negative testing for infection. Such patients are often concerned about malodour as well, but admit that no one else is aware of this. Very likely, the patient has become convinced that she is abnormal via either internet sources or sexual partners. There are others who have obsessive-compulsive tendencies that make them focus on their VD.

The patient will usually have begun to wear pantyliners, often 24 hours per day, and may be using a variety of feminine hygiene products. She is often distressed and keen for the heavy VD to be ‘fixed’. A diagnosis of normality is usually not reassuring, because her concern is for the discharge to be reduced regardless of whether it is normal or not.

This can be a very difficult consultation. Patient pressure to try more treatments should be resisted and, instead, advice about managing the discharge should be given. This involves explanation of the concept of a ‘range’ of normal discharge and moving towards an acceptance of this situation. It also involves recommending a reduction or elimination of the use of pantyliners and feminine hygiene products. Changing underwear during the day instead of wearing pantyliners can help and reducing reliance on occlusive clothing is recommended.

Conclusion

Abnormal VD is often assumed to be infective. However, there are a number of common and uncommon non-infective vulval and vaginal conditions that must be considered in order to help our patients.