Pruritus vulvae

Question 1

Which dermatological conditions cause pruritus vulvae?

Answer 1

• Contact dermatitis
• Psoriasis
• Seborrhoeic dermatitis
• Lichen simplex
• Lichen planus
• Lichen sclerosus
• Symptomatic dermatographism - localised urticaria triggered by direct firm touch, scratching or rubbing

Question 2

What infections and infestations can cause pruritus vulvae?

Answer 2

• Candidiasis
• Trichomoniasis
• Bacterial vaginosis
• Genital herpes simplex
• Pubic lice (pediculus pubis)
• Scabies (sarcoptes scabiei)

Question 3

Which malignant and premalignant conditions may cause pruritus vulvae?

Answer 3

Malignant neoplasms of the vulva - SCC account for 90% of which 60% are due to HPV; often 65-75 year olds; vulval lichen sclerosus or planus predispose to vulval neoplasms.

Pre-malignant - vulval intraepithelial neoplasia (VIN) - may be symptom-free but most are itchy or burning sensation; usually 1 or more slightly raised, red/white/pink/brown well defined lesions that can develop into invasive cancer but only after ~10 years

Question 4

What are the two types of VIN?

Answer 4

1. High grade squamous intraepithelial lesion (usual-type) — risk factors include smoking and immunosuppression.
2. Intraepithelial neoplasia (differentiated-type) — associated with lichen sclerosus.

Question 5

What hormonal changes can cause pruritus vulvae?

Answer 5

• Atrophic vulvovaginitis - due to declining oestrogen peri-menopause or in pregnant women where high prolactin may be antagonistic on oestrogen production
• Pregnancy - due to increased physiological vaginal discharge and risk of candidal vulvovaginitis

Question 6

What GI conditions can cause pruritus vulvae?

Answer 6

• GI disease - prolonged contact of stool with vulval skin due to faecal incontinence or poor perianal hygiene e.g. IBS, Crohn’s., UC, anal fissures.
• Urinary and faecal incontinence - inflammation may present as pruritus

Question 7

What systemic conditions can cause pruritus vulvae?

Answer 7

• Any generalised cause of pruritus e.g. drugs (NSAIDs, tetracyclines like dyxycycline), systemic disease like renal/hepatic, diabetes, thyroid, Fe def anaemia.
• Stress
• Psychological problems

Question 8

What can cause contact dermatitis leading to PV?

Answer 8

• Proprietary creams
• Topical antibiotics e.g. neomycin
• Barrier contraceptives or lubricants
• Perfumes, soaps, bubble baths, wet wipes
• Detergents, fabric conditioners, bleaches, dyes

Question 9

What can vulval psoriasis look like? How common is it to have genital involvement in psoriasis?

Answer 9

Classic psoriatic lesion* is replaced with a poorly demarcated, erythematous plaque with minimal scale and shiny texture due to moisture and friction of the skin folds

>30% of people have genital involvement in psoriasis

*Well-demarcated border, with erythematous plaques and silvery scale

Question 10

What does lichen simplex of the vulva look like? Who is affected?

Answer 10

• Often seen in those with atopic skin disease
• Localised plaque of chronic eczematous inflammation created by rubbing or scratching of the skin
• May look leathery or lichenified

Question 11

What does lichen planus of the vulva look like? What is a risk of this?

Answer 11

Appear as:

• erosive, glazed or glossy erythematous plaques;
• bluish-purple, shiny, flat-topped papules
• with small white dots or lines (Wickham’s striae);
• or uniformly white hyperkeratotic plaques.

Small risk of SCC development

Question 12

What does lichen sclerosus of the vulva look like? What is a risk associated with it?

Answer 12

NB: affects anogenital area more than other cutaneous surfaces

• Any area from clitoral hood to perianal region affected but not the vagina
• Hypopigmented-to-white, crinkled, fragile plaques classically distributed in a figure eight pattern around the vulva, perineal body, and perianal skin.

Risks: scarring may cause loss of valvular architecture, resoprtion of labia minora but not loss of clitoris. <5% risk of SCC.

Question 13

What are some rare dermatological causes of pruritus vulvae?

Answer 13

All very rare:

Fox-Fordyce disease - small dome-shaped flesh coloured to red papules affect all hair follicles in the area

Hailey-Hailey disease - blistering disease affecting skin fold and causing malodourous plaques

Darier disease - persistent greasy, scaly papules which are firm and may feel like sandpaper.

Question 14

What is shown?

Answer 14

Fox-Fordyce disease

Question 15

What is shown?

Answer 15

Hailey-Hailey disease

Question 16

What is shown?

Answer 16

Darier disease

Question 17

How do you manage pruritus vulvae of an unknown cause?

Answer 17

1. Symptomatic treatment e.g.
   
   • emollient (protects skin from local irritants)
   • mildly anxiolytic antihistamine (hydroxyzine - reduces nocturnal itching)
2. Short trial of low potency corticosteroid e.g. 1-2 weeks hydrocortisone 1% oitment
3. Refer for further investigation to dermatologist, gynaecologist, vulval clinic.

Question 18

What self-care advice should you give to women with pruritus vulvae?

Answer 18

• Shower rather than bathe
• Use emollient to clean vulvae rather than soap
• Avoid chemicals like shampoo, bubble bath, wet wipes
• Avoid tight-fitting clothes or synthetic underwear
• Avoid fabric conditioner

Question 19

What investigations can you consider for pruritus vulvae?

Answer 19

1. Bloods e.g. FBC, TFTs, ferritin, U&Es, LFTs, HbA1c etc to exclude systemic causes
2. Vaginal swabs for candida, BV or trichomoniasis
3. Referral for patch testing
4. Referral for consideration of skin biopsy