Genital dermatology

Overview

Many non-sexually transmitted conditions can affect the genital skin.
This guideline introduces the reader to some common skin conditions that might present on the genital skin (for STI related dermatology).
Dermnetnz.org is a good reference.

Possible causes of dermatological symptoms are varied and may include:

Normal anatomical variants
Fungal: dermatophyte (tinea), candidiasis
Viral: human papillomavirus (HPV), molluscum contagiosum, human herpes virus (HHV), human immunodeficiency virus (HIV)
Bacterial: syphilis, donovanosis, Staphylococcus
Parasites: scabies, lice
Inflammatory conditions: eczema, psoriasis, lichen simplex, hidradenitis suppurativa
Autoimmune conditions: lichen scleroses, lichen planus, inflammatory bowel disease-associated ulceration
Trauma: sexual trauma, self-inflicted trauma, assault
Malignancy: precancerous or cancerous lesions
Other: fixed drug eruptions, medication side-effects (contact dermatitis).

Symptoms	Consideration
Itch	Associated with the need to scratch – may be painful or pleasant
Burning, stinging, dysaesthesia	Unpleasant sensation not associated with a need to scratch
Different appearance	Colour (hyper- or hypo-pigmentation), red/purple, textured, pealing, tearing, fissured, dry, scaley, lichenified (thickened), abrasions, inflammation, sloughing moist skin, increased smegma (men and women), offensive smell
Dyspareunia	Painful sexual intercourse, may include pain with non-penetrative sexual intimacy
Asymptomatic	Signs of skin conditions found incidentally on examination
Lesions	Papules, cysts, pustules, plaques, scale, patches, ulcers, flat, raised, erythematous base, dry, moist, blistered, wart-like, generalised, individual, well demarcated, erosive, nodular

Always examine from head to toe as many genital skin conditions are not sexually transmitted and can be found elsewhere – including nails, mouth, hairline, behind ears, natal cleft, buttocks.

Any investigations will depend on the presenting complaint or clinical suspicion of infection – e.g. syphilis, HIV, hepatitis, herpes simplex virus (HSV).
Many dermatological conditions do not require any investigations at the site.
Use of photography for the patient record (to show regression or resolution of symptoms) or to send to a specialist is useful.
Skin biopsy may be useful to confirm diagnosis.

Paediatric presentations – refer to a specialist
Severe associated anxiety – refer to psychological services.

Diagnosis	Recommended	Alternative
Lichen simplex	Topical mid or potent strength corticosteroid ointment, emollients, antihistamines
Lichen planus	Potent topical corticosteroid ointment	Requires specialist review
Lichen sclerosis	High strength topical corticosteroid ointment for several weeks then titrated to weekly use	Requires specialist review, precancerous condition
Dermatitis	Topical mid or potent strength corticosteroid ointment, emollients	Emollients to wash and moisturise
Psoriasis	Topical mid or potent strength corticosteroid ointment	Emollients, specialist referral if severe
Pruritis ani	Daily mild topical corticosteroid ointment Worming medication	Antihistamines
Hidradenitis suppurativa	Doxycycline 100 mg daily	Clindamycin 2% cream applied to affected area daily Specialist review for severe disease
Scabies and lice	Permethrin cream	Ivermectin
Syphilis	See guidelines
HIV	See guidelines
HSV	See guidelines

Treatment advice

Use an ointment on genital skin
If no resolution refer to a sexual health service or dermatologist
Refer to the specific guideline if a sexually transmitted infection (STI) is suspected or confirmed

Genital skin care

Avoid soap, perfumed products, bleaches and other irritants or allergens
Ensure skin hygiene is maintained with cool water and a soft cloth but avoid over-cleaning
Wear loose cotton clothing and avoid overheating
Use emollients for washing and moisturising skin (e.g. sorbolene cream)
Try lubricant or emollient to shave pubic hair.