Skin rash - genital
Overview
Genital rashes are common and many patients assume that they are associated with an STI, whereas they are often simply a dermatological condition.
Possible causes
- Candida
- Lichen simplex chronicus, lichen sclerosus and lichen planus
- Dermatitis, psoriasis and pruritis ani.
Clinical presentation
| Symptoms | Comments/Considerations |
|---|---|
| Itch | Associated with the need to scratch |
| Burning, dysaesthesia | Unpleasant sensation not associated with an irresistible need to scratch |
| Colour change in skin | Red, white or haemorrhagic patches |
| Change in texture of skin | Thickened or thin areas of skin in normal skin background |
Diagnosis
| Diagnosis | Site/Specimen | Test |
|---|---|---|
| Candida | Vulva swab, high vaginal swab or self-collected vaginal swab | Microscopy, gram stain and culture |
| Lichen simplex, planus or sclerosus | Vulva | Biopsy |
| Dermatitis or psoriasis | Vulva | Biopsy |
| Pruritis ani | Perianal swab | Swab for culture |
Investigations
- Skin biopsy for candida where swabs are negative and erythema with splitting is present.
- Biopsy area of skin with worst appearance or take multiple biopsies if areas look markedly different.
Specimen collection
Clinician collected for NAAT/culture/microscopy
Urethral swabs for microscopy should be collected when the patient has not urinated for at least 1 hour and only if the patient has frank urethral discharge. Squeeze the urethra to express the discharge and collect on urethral swab. It is not necessary to insert the swab into the urethra.
Rectal swabs should be collected by inserting a sterile swab 2-4cms into the anal canal and moving the swab gently side to side for 10-20 seconds.
Pharyngeal swabs should be collected from the tonsils and oropharynx.
High vaginal swab of vaginal discharge smeared onto a glass slide, air dried and sent for microscopy. Swab inserted into transport medium for culture.
Self-collection of samples for NAAT testing
Vaginal swab: instruct the patient to insert the swab into the vagina like a tampon and then remove and place into the transport tube.
Rectal swab: instruct the patient to insert the swab into the anal canal 2-4cms and then remove and place into the transport tube.
FPU (First pass urine): Collect approximately 20 ml (1/3 of the standard urine jar) of the first part of the urine stream in a specimen jar at the time you are consulting the patient. The patient does not need to have held their urine for more than 20 minutes prior to specimen collection. A midstream urine (MSU) or early morning specimen (i.e. first void urine) are not required for NAAT.
Click here for information on how to describe self-collection technique to a patient.
Special considerations
- Infection with uncommon species of candida may require sensitivity testing.
- Always confirm recurrent candida with repeat testing as not all itch is candida.
- Re-biopsy if an unusual area appears after successful treatment.
Management
| Principal Treatment Options | ||
|---|---|---|
| Diagnosis | Recommended | Alternative |
| Candida - simple vaginal | Vaginal azole creams (eg. clotrimazole 10% vaginal cream, 1 applicatorful intravaginally at night, as stat dose or 3-7 days course) | Fluconazole 150mg PO, stat |
| Candida - recurrent or chronic vaginal | Treat each episode with longer course of azole cream (rather than stat dose) and/or induction with fluconazole 150mg PO, for 3 doses, 3 days apart, followed by maintenance with fluconazole 100mg PO, weekly for 6 months | Itraconazole 100mg PO, daily until asymptomatic then 100mg weekly for 6 months |
| Candida - vulval skin | At least 21 days of topical azole cream, TDS | May require longer treatment |
| Lichen simplex | Daily topical mid strength corticosteroid ointment | Oral antihistamines may help to break the itch-scratch-itch cycle |
| Lichen planus | Daily high strength topical corticosteroid ointment | May require specialist review |
| Lichen sclerosus | Daily high strength topical corticosteroid ointment | May require specialist review |
| Dermatitis | Daily topical mid strength corticosteroid ointment | Cream if weeping skin |
| Psoriasis | Daily topical mid strength corticosteroid ointment | Coal tar and emollients |
| Pruritis ani | Daily mild topical corticosteroid ointment | Oral antihistamines may help to break the itch-scratch-itch cycle |
Treatment advice
- Infection with uncommon species of candida may require specialist review
- Treat until symptoms and signs have resolved
- Lichen planus and lichen sclerosus require long term maintenance topical steroid and regular review. Commencing these treatments without biopsy confirmed diagnosis is not recommended
- Dermatitis and psoriasis may require long term maintenance or may be treated intermittently
- Ointment is most useful for dry skin and cream for wet, weeping skin
- Creams have preservatives that may cause irritation. Consider this as a cause if not responding.
Other immediate management
- 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
- Burow’s solution (13% aluminium acetate) diluted 1:20-1:40 with cold water applied as a cold compress BD may be helpful for burning itchy skin
- Use daily sorbolene for moisturising skin.
Follow up
- Follow up one month after commencement of treatment
- Reduce regularity of treatment application after symptoms or signs have resolved
- Review patients with lichen planus or lichen sclerosus at least annually once stable.
Auditable outcomes
90% of patients with lichen sclerosus and lichen planus under regular review.
References
- Russell D, Bradford D and Fairley C. Sexual Health Medicine. 2nd edition. IP Communications. 2011