There is an identifiable cause for pruritus vulvae in most women.

• Confirm that the woman is experiencing vulval itch, not vulval pain (which is outside the scope of this topic).
• Take a careful history — this may find an underlying cause for the vulval itch. Ask about:
• Duration and timing of symptoms
• How long have symptoms been present? — Acute itch is generally due to infection or acute contact dermatitis.
• Is the itch worse at night? — Nocturnal vulval itching may indicate lichen sclerosus, lichen simplex, or threadworm infestation (particularly if combined with peri-anal itch).
• Associated symptoms
• Is the itch confined to the vulval area? — Itch elsewhere may indicate a more generalized problem, including scabies.
• Is there vaginal discharge? — Discharge may indicate infection, such as candidiasis, bacterial vaginosis, or trichomoniasis.
• Hygiene practices
• Could hygiene practices be causing symptoms? — The use of creams, perfumes, deodorants; sanitary wear containing bleach; douches; soaps; wipes (baby or hygiene); moist toilet tissues; or simply excessive washing may result in vulval irritation or even contact dermatitis.
• Use of topical vulval preparations
• Could self-administered treatments be causing or aggravating symptoms? — Some women may develop irritation secondary to use of antifungal creams for presumed candidiasis, hormone replacement therapy creams, or pessaries.
• What contraception is being used? — Some women are allergic to spermicides, or the latex in condoms and diaphragms.
• Other conditions
• Is the woman known to have a generalized skin disorder that can affect the vulval area, such as dermatitis or psoriasis?
• Does the woman have a personal or family history of atopic conditions (for example hay fever, asthma, eczema)?
• Does the woman have diabetes mellitus? — Diabetes increases the risk of candidal infection.
• Does the woman have a systemic illness that could cause itch, such as renal or hepatic impairment, or anaemia?
• Is the woman menopausal? — Atrophic vaginitis may be the cause of the symptoms.
• Is the woman breastfeeding? — Breastfeeding can result in lowered oestrogen levels and consequent vulval symptoms.
• Does the woman have faecal or urinary incontinence? — These can damage the vulval skin either directly or indirectly by the use of sanitary products or over washing.
• Assess the severity of symptoms and the impact this is having on the woman — in particular enquire into psychosexual problems, low mood, loss of sleep pattern, and feelings of anxiety.
• Examine:
• The anogenital region  — examination findings may indicate an underlying cause, such as signs of candidiasis, dermatitis, psoriasis, atrophic vaginitis, lichen sclerosus, or lichen planus.
• The mouth — examination may find signs of lichen planus.
• The skin —  examine for signs of psoriasis (for example on scalp, elbows, knees, and nails), and eczema (which may be seen on any area of the skin).
• For a discussion of the possible causes of pruritus vulvae, and their differentiating features, see Causes.

• Recommendations for the assessment of pruritus vulvae are based on expert opinion [Nunns, 2002; Welsh et al, 2003; Doxanakis et al, 2004; Weichert, 2004; Bohl, 2005; BASHH, 2007; RCOG, 2010].
• Identifiable cause
• The statement that there is an identifiable cause for pruritus vulvae in most women is based on published expert opinion [Doxanakis et al, 2004].

• Most women who present with pruritus vulvae have an identifiable cause [Doxanakis et al, 2004; Bohl, 2005]:
• Dermatological conditions — contact dermatitis is thought to be the most frequently encountered and avoidable condition seen in clinics that specialize in vulval disorders.
• Infection and infestations.
• Neoplastic conditions.
• Hormonal changes.
• Gastrointestinal and urinary incontinence.
• Systemic conditions.
• Idiopathic pruritus vulvae is thought to be uncommon.

• Contact dermatitis (most common cause of pruritus vulvae) — reaction to proprietary creams (especially those containing local anaesthetics); topical antibiotic preparations (neomycin); barrier contraceptives; perfumes; soaps; bubble baths, wet wipes; textile dyes; detergents; fabric conditioners (can cause contact allergy or aggravate vulval symptoms); and bleaches, dyes, and perfumes in sanitary wear, such as panty liners, tampons, and sanitary towels.
• Psoriasis — well-demarcated border, absence of scale when affecting the vulval area, often with typical psoriasis lesions elsewhere on the body.
• For more information, see the CKS topic on Psoriasis.
• Seborrhoeic dermatitis — ill-defined border, some scaling, with or without involvement of other sites, such as the axillae, face (eyebrows or nasolabial folds), anterior chest, or scalp.
• For more information, see the CKS topic on Seborrhoeic dermatitis.
• Lichen simplex — thickened plaques with exaggerated skin markings over the hair-bearing labia majora and sparing the mucosal vulval skin and labia minora (the end result of an itch-scratch-cycle, regardless of the initial underlying cause of the itch).
• Lichen planus — erythema and or erosive pattern, ulceration with intense pruritus, destruction of vulval architecture (possibly with other sites involved such as the nails and buccal mucosa). Lesions are bluish-purple, shiny, flat-topped papules with small white dots or lines (Wickham's striae). There is a small risk of squamous cell carcinoma developing in women with lichen planus (less than 3%).
• Lichen sclerosus — lesions are white papules and or plaques, often associated with areas of bruising and usually found on the interlabial sulci, labia minora, clitoral hood, clitoris, perineal body, and perineum. Affected skin appears somewhat crinkly, like cigarette paper. Bleeding into the affected areas produces red or purple purpuric lesions. Scarring and loss of tissue can lead to burying of the clitoris, loss of the labia minora, and narrowing of the vulval introitus. There is a small risk of squamous cell carcinoma developing in women with lichen sclerosus (less than 5%).
• Fox–Fordyce disease (very rare) — small dome-shaped papules, with or without involvement of the axillae; intensely itchy and often presenting as lichenification (grossly thickened skin with accentuated skin markings).
• Hailey–Hailey disease (very rare) — vesicles erupt causing pruritus, with or without involvement of the axillae and sides of the neck. It is also known as 'familial benign chronic pemphigus', and is an inherited autosomal dominant condition. It is easily mistaken for intertrigo or dermatitis.
• Darier's disease (very rare) — warty plaques, which may be macerated and malodorous, possibly with the involvement of seborrhoeic areas of the trunk, flank, and face. An autosomal dominant condition, which may be confused with Hailey–Hailey disease.
• Symptomatic dermatographism — a form of localized urticaria triggered by a direct firm touch, scratching, or rubbing.
• Images of the different conditions listed above that can cause pruritus vulvae can be found at www.dermnet.com.

The information and descriptions of the underlying causes of pruritus vulvae is based on published expert opinion [Nunns, 2002; Doxanakis et al, 2004; Margesson, 2004; Bohl, 2005].

Contact dermatitis

• The information that contact dermatitis is the most frequently encountered and avoidable condition seen in clinics that specialize in vulval disorders is based on published expert opinion [ACOG, 2008] and is supported by one small observational study. In the study, of 141 women with chronic vulval symptoms who were referred to a dermatologist, dermatitis was identified as the commonest cause (54%). Other commonly seen conditions were lichen sclerosus (13%), chronic vulvovaginal candidiasis (10%), dysaesthetic vulvodynia (9%), and psoriasis (5%) [Fischer, 1996].

Lichen simplex and lichen planus

• The descriptions of lichen simplex and lichen planus are published expert opinion [Nunns, 2002; Farage et al, 2008].

Lichen sclerosus

• The description of lichen sclerosus is published expert opinion [BAD, 2010].

• Infections and infestations that can cause pruritus vulvae
• Candidiasis — pruritus, discharge, erythema, oedema, white plaques, and satellite erythematous lesions. The typical discharge and swelling associated with acute candidiasis are generally absent in recurrent vulvovaginal candidiasis, whereas skin fissuring and irritation after intercourse are more common.
• For more information, see the CKS topic on Candida - female genital.
• Trichomoniasis — often severe pruritus, with thin, frothy, malodorous vaginal discharge.
• For more information, see the CKS topic on Trichomoniasis.
• Bacterial vaginosis — mild pruritus (not always present) with thin vaginal discharge.
• For more information, see the CKS topic on Bacterial vaginosis.
• Herpes simplex of the genitalia — can present as pruritus, but may present with vesicles, ulcers, cutaneous hyperaesthesia, perineal burning with or without severe dysuria, and systemic symptoms.
• For more information, see the CKS topic on Herpes simplex - genital.
• Pubic lice (Pediculus pubis) — intense vulval pruritus, possibly with sky-blue spots on trunk and thighs. Lice may be seen on hair, pubis, trunk, legs, axillae, scalp, eyelashes, and eyebrows.
• For more information, see the CKS topic on Pubic lice.

The information and descriptions of the underlying causes of pruritus vulvae is based on published expert opinion [Nunns, 2002; Doxanakis et al, 2004; Margesson, 2004; Bohl, 2005].

• Malignant neoplasms of the vulva (uncommon).
• Squamous cell carcinomas account for 90% of malignant disease of the vulva. Other less common neoplastic conditions include peri-anal intraepithelial neoplasia, basal cell carcinoma, melanoma, and carcinoma of Bartholin's gland.
• Squamous cell carcinomas often arise from pre-existing background disease. Unlike vulval intraepithelial neoplasia (VIN) and Paget's disease, squamous cell carcinomas are rarely itchy; they usually present as a lump or ulcer and are usually tender:
• In elderly women, the background disease is most likely to be lichen sclerosus or lichen planus.
• Vulval intraepithelial neoplasia — is a pre-malignant skin lesion of the vulva and is the most likely background disease in young women. This is usually linked to the wart virus.
• Vulval intraepithelial neoplasia (VIN) is a pre-malignant skin lesion of the vulva.
• If left untreated, VIN may go away by itself (especially the type of VIN known as 'Bowenoid papulosis'), or it may turn into an invasive cancer in later years. On average, it takes well over 10 years for VIN to progress to cancer.
• Vulval intraepithelial neoplasia may occur in women of all ages; the average age of women with VIN is 45–50 years of age, although currently an increasing number of younger women (even teenagers) are presenting with the condition.
• Vulval intraepithelial neoplasia may be completely symptom-free, however most women present with:
• Mild to severe vulval itching.
• Mild to severe vulvar burning.
• One or more slightly raised, well-defined skin lesions that may be pink, red, brown, or white.
• There are two types of VIN:
• Usual-type VIN — caused by persistent infection with high-risk human papillomavirus. Risk factors for developing usual type VIN include smoking and immunosuppression.
• Differentiated-type VIN — associated with lichen sclerosus. This is less common than usual-type VIN (accounts for less than 2–5% of all VIN lesions).
• Extra mammary Paget's disease (very rare) — a cutaneous neoplasm with a chronic eczema-like rash of the skin around the anogenital regions of males and females. A common symptom is a mild to intense itching of a lesion found around the groin, genitalia, perineum, or peri-anal area. Pain and bleeding may occur from scratching lesions that have been around for a long time. Thickened plaques may form that can become red, scaly, and crusty. Plaques are fixed (unchanging over a few weeks), with sharply demarcated margins and are usually asymmetric, often only affecting one side of the vulva (or peri-anal skin) Although they may appear similar to eczema, they fail to clear up with topical steroid creams.

The information and descriptions of neoplastic conditions that may cause pruritus vulvae, including vulval intraepithelial neoplasia, is based on published expert opinion [Canavan and Cohen, 2002; DermNet NZ, 2007].

• Atrophic vulvovaginitis
• In peri- and postmenopausal women, declining oestrogen levels may contribute to vaginal and vulval changes that result in vulvovaginal itching, dryness, and sometimes burning, although the natural aging process may be a key factor in this change. The vulva will look atrophic, pale, and dry, and if irritated may show erythema, petechiae, telangiectasia, or fissuring (these signs and symptoms are similar to the features of lichen sclerosus). The vaginal epithelium will be dry, pale, thin, and smooth owing to the loss of rugae. Cessation of menstruation and other symptoms, such as hot flushes, may indicate that the cause is the menopause.
• In breastfeeding women, elevated prolactin levels can have an antagonistic effect on oestrogen production, and may result in low oestrogen levels. This can lead to vaginal dryness, itching, burning, and irritation.
• Pregnancy
• Pregnancy can cause perineal pruritus through vulval engorgement. Pregnancy is also associated with increased vaginal discharge as a result of increased hormone levels, and an increased incidence of candidal vulvovaginitis.

The information that hormonal changes may cause pruritus vulvae is based on published expert opinion [Bohl, 2005].

• Gastrointestinal disease — from prolonged contact of stool with the vulval skin due to faecal incontinence or poor peri-anal hygiene.
• Urinary incontinence — which makes the vulval skin moist and macerated.

The information that gastrointestinal disease and urinary incontinence are possible underlying causes of pruritus vulvae is taken from published expert opinion [Bohl, 2005].

• Any cause of generalized pruritus — including drug reactions and systemic diseases, such as renal or hepatic disease, diabetes, iron deficiency anaemia, lymphoma, other haematological abnormalities, and thyroid dysfunction.
• For more information on managing generalized pruritus, see the CKS topic on Itch - widespread.
• Psychological problems — may occasionally present as pruritus vulvae.
• Stress — may be a cause of itch, or if not an initial cause, an exacerbating factor causing prolongation of symptoms or a flare-up.

The information and descriptions of the underlying causes of pruritus vulvae is based on published expert opinion [Nunns, 2002; Doxanakis et al, 2004; Margesson, 2004; Bohl, 2005].

• Investigations that might be helpful
• Fasting blood glucose level, if diabetes mellitus is suspected — diabetes may cause general pruritus.
• Routine screen, including full blood count, serum ferritin, and thyroid function tests.
• Iron deficiency anaemia, lymphoma, other haematological abnormalities, and thyroid dysfunction may cause general pruritus. For more information on the investigation of general pruritus, see the CKS topic on Itch - widespread.
• Vaginal swabs for Candida sp. — swabs can be considered in all women, as there may be little or no discharge with chronic vulvovaginal candidiasis.
• Vaginal swabs for other infections, if suspected, such as bacterial vaginosis or trichomoniasis.
• If a sexually transmitted infection is suspected, ideally, refer the woman to a service specializing in sexual health or a general practice providing an enhanced sexual health service to confirm the diagnosis.

These recommendations are based on expert opinion [Nunns, 2002; Welsh et al, 2003; Doxanakis et al, 2004; Weichert, 2004; Bohl, 2005; BASHH, 2007; RCOG, 2010].