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Genital skin diseases

 

Genital skin diseases

 

Genital skin diseases in adult females

 

The genital area is affected by dermatoses that affect other parts of the skin (see Table 1, below), but management in this area is complicated by the sensitivity and thinness of the skin, the tendency to maceration and infection, and the psychological overlay of a dermatosis affecting this area. Genital itch is more commonly due to dermatoses (such as dermatitis and psoriasis) than infection, and it should not be assumed that a fungal infection is present without microbiological confirmation by low vaginal swab and/or skin scrapings from the genital skin.

 

 

	common	uncommon	rare
prepubertal females	dermatitis (atopic, irritant), psoriasis, molluscum contagiosum, staphylococcal folliculitis, pinworm infestation	lichen sclerosus, streptococcal vulvovaginitis, genital warts, genital herpes, fusion of the labia minora, benign naevi (pigmented, epidermal)	aphthous ulcers, vulval bullous pemphigoid, recurrent erythema multiforme, fixed drug eruption
postpubertal, premenopausal females	dermatitis (atopic, seborrhoeic, irritant, allergic), lichen sclerosus, psoriasis, chronic candidiasis, genital warts, molluscum contagiosum, genital herpes, tinea, pubic lice	lichen planus, bacterial infection, chronic pain syndromes (neuropathic pain, vestibulodynia, psychogenic pain), hidradenitis suppurativa, aphthous ulcers, sexually transmissible infections, group A/B streptococcal vaginitis, staphylococcal vaginitis, benign tumours (sebaceous cysts, hidradenoma papilliferum, naevi, seborrhoeic keratosis, angiokeratomas)	bullous disorders, desquamative inflammatory vaginitis, carcinoma (vulval intraepithelial neoplasia, squamous cell carcinoma, basal cell carcinoma, melanoma), recurrent erythema multiforme, Behçet’s syndrome, fixed drug eruption
postmenopausal females	dermatitis (atopic, seborrhoeic, irritant, allergic), lichen sclerosus, psoriasis, atrophic vulvovaginitis	lichen planus, bacterial infection, chronic pain syndromes (neuropathic, psychogenic), benign tumours (angiokeratomas, seborrhoeic keratosis, sebaceous cysts, hidradenoma papilliferum), chronic candidiasis secondary to hormone replacement therapy	bullous disorders, desquamative inflammatory vaginitis, carcinoma (vulval intraepithelial neoplasia, squamous cell carcinoma, extramammary Paget’s disease, melanoma), recurrent erythema multiforme, Behçet’s syndrome, fixed drug eruption

 

Genital dermatitis

 

Genital dermatitis presents with itching, burning and scratching-induced soreness. The rash is a nonspecific scaly erythematous eruption. In longstanding cases lichenification, particularly of the perianal area and labia majora, is common. Superinfection, most often with Candida albicans and less often with Staphylococcus aureus, may occur. Dermatitis may occur elsewhere on the skin, but involvement of the genital area alone can occur. Irritancy from applied substances, occlusive clothing, sanitary pads and body secretions complicates the clinical picture. Incontinent patients, particularly those who are confined to a wheelchair, may suffer from intractable genital dermatitis. In obese patients, sweating and maceration may be an intractable source of irritancy. Occasionally allergy to medications, preservatives, perfumes or seminal fluid may occur. The presence of vaginal candidiasis can contribute to dermatitis on the external genitalia through a variety of mechanisms and may be a potential exacerbating factor. Infective vaginal secretions may be irritating to the vulval skin.

In perimenopausal, postmenopausal and lactating women, oestrogen deficiency may precipitate dermatitis. In these patients the vaginal mucosa is also dry, thin and susceptible to trauma, which usually manifests as splitting around the introitus. Skin dryness may also result in a mild dermatitis. The main complaint from these patients is dyspareunia, but in those with dermatitis, itching may also be a problem. This is commonly known as atrophic vulvovaginitis.

 

Rule out factors such as superinfection (by bacterial culture and scrapings of skin), and vaginal infection and other vaginal pathology (by speculum examination and low vaginal swab). In patients who have received antifungal therapy within the last month, there may be a false negative result when seeking fungal infection.

Avoid the following: soap, excessive washing and bubble bath, may be used instead); wiping back to front; and tight occlusive clothing. Advise weight reduction in obese individuals. Eliminate irritants and allergens. Address incontinence issues. Use

a bland emollient topically, 3 times daily PLUS a potent topical corticosteroid topically, daily until itching has resolved and skin has normalised REDUCE TO hydrocortisone 1% topically, daily for 2 weeks. Then cease, but be ready to re-use at the first sign of itching.

 

If there is no improvement in 2 weeks with the potent corticosteroid, refer the patient to a dermatologist.

Resistant areas of lichenification may be treated with

1	triamcinolone acetonide 10mg/mL intradermally, at 6-weekly intervals until resolved
	OR
2	betamethasone (acetate+sodium phosphate) 5.7 mg/mL intradermally, at 6-weekly intervals until resolved.

 

 

If oestrogen deficiency is suspected, confirm with serum follicle stimulating hormone (FSH) and oestradiol testing. Topical oestrogen replacement (with oestradiol pessaries or oestriol cream or pessaries), avoidance of irritants, and use of emollients usually resolves the problem. If a topical corticosteroid is required, use only hydrocortisone 1%, as strong corticosteroids exacerbate the tendency to atrophy. If systemic hormone replacement therapy is started, it is not necessary to continue topical oestrogen.

 

Rest, together with

1	soaks in a very dilute saline bath (add a cup of salt to bathwater)
	OR
1	application of pads soaked in aluminium acetate 13% (Burow’s) solution diluted 1:20 or 1:40 before use, for 10 to 15 minutes 3 times daily
	OR
1	application of pads soaked in potassium permanganate (Condy’s crystals) 0.1% solution diluted 1:10 before use, for 10 to 15 minutes 3 times daily
PLUS
	a potent topical corticosteroid topically, once or twice daily until resolved.

 

Seek evidence of bacterial and fungal infection of vagina and perineal skin, and treat if present. Even colonisation in the absence of frank infection may make dermatitis more difficult to treat (superantigen phenomenon).

 

Proven infection should be treated.

Candida albicans

Candida albicans generally infects only the oestrogenised vagina, so prepubertal girls and postmenopausal women who are not using hormone replacement therapy are not affected.

nystatin 100 000 units/g cream topically, 3 times daily to skin surface until eruption has cleared.

 

If vaginal swabs are positive, treat vaginal reservoir with

1	nystatin 100 000 units/5 g vaginal cream (1 applicatorful) or 100 000 units pessary intravaginally, 12-hourly for 7 days
	OR
2	clotrimazole 1% vaginal cream (1 applicatorful) or 100 mg pessary intravaginally, for 6 nights
	OR
2	clotrimazole 2% vaginal cream (1 applicatorful) intravaginally, for 3 nights
	OR
2	clotrimazole 10% vaginal cream (1 applicatorful) intravaginally, as 1 dose at night.

 

Imidazoles (eg clotrimazole) are commonly irritating to genital skin when dermatitis is present.

If the patient is intolerant of topical therapy or would prefer to use oral therapy, and infection is microbiologically proven and the patient is not pregnant, use

fluconazole 150 mg orally, as 1 dose.

 

Staphylococcus aureus

Use

mupirocin 2% ointment or cream topically, 3 times daily for 5 days (mupirocin ointment contains macrogols, which may cause transient stinging).

 

More severe cases or cases that do not respond to topical therapy may require oral antibiotics (di/flucloxacillin 250 to 500 mg orally, 6-hourly for 10 days). However, if the patient has a positive vaginal swab for Candida albicans or a history of vaginal candidiasis, topical therapy with mupirocin is preferable as oral antibiotics will complicate the clinical picture by exacerbating vaginal candidiasis.

 

When treatment resistance is encountered in genital dermatitis it is usually due to one of 4 factors:

·            noncompliance with the environmental modifications that are essential to treatment success—check compliance

·            infection—repeat microbiology requesting that the laboratory report any nonalbicans yeast species that are present, as they may result in a resistant vulvovaginitis

·            allergy to an applied substance—rule out allergy to topical preparations by patch testing (see Allergy testing)

·            underlying psoriasis—the diagnosis of dermatitis may not be correct. Check the rest of the patient’s skin for other signs of psoriasis, however subtle (scalp scaling, rash on elbows, knees, nail pits).

 

Refer women with a persistent unexplained discharge to a gynaecologist. Biopsy may be required.

Genital psoriasis

Psoriasis may be confined to the genital or perianal area with little sign of the condition elsewhere. The clinical picture is of a glazed erythematous plaque, usually well defined without the scale associated with psoriasis on other parts of the skin. Involvement of the perianal area and natal cleft is common. The main complaint is usually itching, but fissuring may cause pain.

In both sexes, there may be minimal signs of psoriasis elsewhere. The following are clues to the diagnosis: psoriatic nail changes; scaliness of the scalp, external auditory meatus, knees and elbows; and a family history of psoriasis.

Take swabs to rule out infection and treat according to findings.

Commence therapy with

methylprednisolone 0.1% in a fatty ointment base topically, once daily. Continue until rash is resolved (this may take several weeks).

 

Then attempt to introduce a tar preparation, commencing with

liquor picis carbonis (LPC) 2% in aqueous cream topically, twice daily. If tolerated, slowly increase strength of LPC up to 8%.

 

If LPC is not tolerated, attempt therapy with ichthammol 2% in aqueous cream.

If tar is not tolerated, maintain control with topical corticosteroids. Attempt to use hydrocortisone 1%; however, this is frequently ineffective alone and intermittent treatment with a more potent preparation, or additional use of a tar cream will usually be necessary. Avoid irritants and use a soap substitute. Refer resistant cases to a dermatologist.

Lichen sclerosus of the genital area

 

Lichen sclerosus, an uncommon and frequently misdiagnosed skin condition, has a predilection for the genital area, and is a relatively common cause of genital skin disease. It is 10 times more common in women than men. It presents as a well-defined white, finely wrinkled plaque, often with purpuric areas and ulceration. Blistering may occur. The condition is typically very itchy; however, it may occasionally be asymptomatic, or present with pain and dyspareunia due to blistering and fissuring. Any part of the external genital and perianal area may be involved, but the vagina is spared. In longstanding untreated cases, atrophy of the vulva and stenosis of the vaginal opening may occur. Lichen sclerosus affects all ages, and is associated with a tendency to autoimmune conditions such as thyroiditis. Untreated lichen sclerosus is associated with squamous cell carcinoma of the vulva in 2% to 6% of cases.

Lichen sclerosus is usually a chronic condition that may run a complicated course in which neoplasia may supervene. Management in consultation with a dermatologist is recommended.

Confirm the diagnosis by skin biopsy. This is most likely to be diagnostic if performed before any treatment is commenced, as topical corticosteroid treatment rapidly changes the typical histopathology.

Seek and treat any associated infection.

Use topical corticosteroids

	betamethasone dipropionate 0.05% in optimised vehicle topically, twice daily for 4 weeks, then daily for a further 8 weeks
	REDUCE TO
	a potent topical corticosteroid topically, daily for maintenance therapy over the next 3 months
	REDUCE TO
	hydrocortisone 1% topically, daily for long-term maintenance (usually required), with return to stronger preparation for management of acute exacerbations.

 

Symptom control is usually achieved within the first month of therapy if a very potent corticosteroid is used initially to bring the disease under control. If cost is an issue (betamethasone dipropionate 0.05% in optimised vehicle is not on the Pharmaceutical Benefits Scheme) start with a potent topical corticosteroid, but be prepared to change to a very potent corticosteroid if treatment fails. A complete return to objective clinical normality is not usually achieved, particularly if scarring or fusion has occurred, and should not be the object of therapy. Maintenance treatment is required in most cases.

Follow-up 6-monthly for an indefinite period for carcinoma surveillance.

There is no place for vulvectomy in the management of lichen sclerosus, unless it is performed for concomitant squamous cell carcinoma of the vulva. In some cases, surgical correction of fusion and stenosis may be indicated.

For treatment of lichen sclerosus in children, see Lichen sclerosus in prepubertal girls.

Vulvovaginal candidiasis

 

Many effective topical preparations are available (imidazoles [eg clotrimazole, econazole, miconazole], nystatin). The following have been shown to be effective in at least 80% of women. Occasionally topical therapy may itself cause irritation. Nystatin, although less effective, is generally better tolerated than the imidazoles.

1	clotrimazole 1% vaginal cream (1 applicatorful) OR 100 mg pessary intravaginally, for 6 nights
	OR
1	clotrimazole 2% vaginal cream (1 applicatorful) intravaginally, for 3 nights
	OR
1	clotrimazole 10% vaginal cream (1 applicatorful) intravaginally, as 1 dose at night
	OR
1	clotrimazole 500 mg pessary intravaginally, as 1 dose at night, with or without use of clotrimazole 1% cream topically, 8- to 12-hourly to vulvovaginal and perianal areas
	OR
2	nystatin 100 000 units/5 g vaginal cream (1 applicatorful) OR 100 000 units pessary intravaginally, 12-hourly for 7 days.

 

If the patient is intolerant of topical therapy or would prefer to use oral therapy, and infection is microbiologically proven and the patient is not pregnant, use

fluconazole 150 mg orally, as 1 dose.

 

If initial treatment fails, review the diagnosis and seek specialist advice.

Symptomatic sexual partners (usually balanitis in the uncircumcised male) should be swabbed and only treated if infection is present (see Balanitis). Many men describe discomfort soon after intercourse, but this is usually an irritant effect that is rapidly relieved by use of 1% hydrocortisone cream.

 

Candida glabrata is the commonest of the nonalbicans species of Candida, which show reduced susceptibility to azoles. Candida glabrata accounts for 5% to 10% of recurrent vulvovaginal candidiasis. In clinically resistant infection, boric acid 600 mg (extemporaneously prepared in a gelatin capsule) intravaginally, daily for 10 to 14 days is effective. Do not use in pregnancy. This condition is recurrent and may need repeated treatment or long-term maintenance therapy.

 

Recurrent vulvovaginal candidiasis (RVVC) is defined as four or more attacks of symptomatic candida vaginitis in a 12-month period.

Chronic candidiasis refers to continuous symptoms due to Candida albicans infection; however, the definition and treatment of this common condition remains an area of controversy. The problem presents with a history, often dating back to teenage years, of vulval itching and burning with premenstrual exacerbation. Typically, it is worsened by courses of systemic antibiotics, and the male partner may become hypersensitive to C. albicans in his partner’s vagina and therefore experience postcoital itching. The appearance is of a nonspecific vulvitis and there is usually no discharge. Diagnosis is based on typical history and repeated positive vaginal swabs (the exact number has not been defined). The presence of diabetes mellitus and iron deficiency anaemia may predispose to candidal infection and these conditions should be ruled out prior to commencing therapy.

Treatment of either chronic or recurrent candidiasis is difficult and often has to be aimed at control rather than cure. It may be effected with either topical or oral antifungal medication, but the latter is easier to use, less likely to produce irritancy and has better patient acceptance. Because there is still no consensus on managing this condition, the following broad principles relating to a 2-stage management plan are recommended.

Induce symptom remission with continuous antifungal treatment. Use

1	a vaginal imidazole (eg clotrimazole) or nystatin (see recommendations above) intravaginally, at night
	OR
2	fluconazole 50 mg orally, daily
	OR
2	itraconazole 100 mg orally, daily
	OR
3	ketoconazole 100 mg orally, daily.

 

The time to achieve remission of symptoms varies from 2 weeks to 6 months.

Relieve itching with

hydrocortisone 1% cream topically, 2 to 3 times daily.

 

Hydrocortisone may be used for itching at any stage. Do not use stronger topical corticosteroids.

Maintain remission with interval therapy; the treatment interval varies from weekly to once a month (eg premenstrually) depending on response. A suitable weekly regimen is

1	fluconazole 150 to 300 mg orally, weekly
	OR
1	itraconazole 100 to 200 mg orally, weekly
	OR
2	clotrimazole 500 mg pessary intravaginally, weekly
	OR
2	nystatin 100 000 units/5 g vaginal cream (1 applicatorful) OR 100 000 units pessary intravaginally, weekly.

 

If oral antibiotics are required for intercurrent infection, the patient may have to return to continuous antifungal therapy after the course is completed to treat an antibiotic-induced flare of their condition.

There is generally no need to treat the male partner or stop a low-dose oral contraceptive pill. However, in postmenopausal women, hormone replacement therapy may predispose to candidiasis and may have to be suspended (see postmenopausal chronic vulvovaginal candidiasis).

Postmenopausal chronic vulvovaginal candidiasis

Chronic candidiasis does not generally occur in the nonoestrogenised vagina. It may, however, appear for the first time in an otherwise healthy postmenopausal woman on systemic hormone replacement therapy. In this setting it is necessary to stop hormone replacement therapy and treat as for chronic vulvovaginal candidiasis until symptoms have resolved.

When the patient has recovered, it may be possible to restart hormone replacement therapy at a lower dose; however, if relapse occurs, the patient will have to decide whether to cease completely, or to combine intermittent preventive antifungal therapy long term with the hormone replacement therapy.

Streptococcal vulvovaginitis

 

There are 4 clinical situations where streptococcal infection can be encountered in the vulva.

 

See Streptococcal perianal dermatitis, vulvitis and balanitis in children.

 

This occurs rarely and usually on a background of dermatitis, lichen sclerosus or psoriasis.

When group A streptococcus is encountered on the skin, use

phenoxymethylpenicillin 250 mg orally, 6-hourly for 10 days.

 

For patients hypersensitive to penicillin, use

roxithromycin 300 mg orally, daily for 10 days.

 

Do not use topical antibiotics because of the risk of cellulitis in Group A streptococcal infection.

 

Group B streptococcus is a commensal in the gastrointestinal and genital tracts of up to 30% of healthy women of childbearing age. Other than in pregnancy it is usually an incidental finding and should be ignored unless there are symptoms of vaginitis.

For management of pregnant women with Group B streptococcal carriage, see Group B streptococcus (Streptococcus agalactiae).

Uncommonly, group B streptococcus may produce a symptomatic vaginitis with a constant irritating discharge. Use

1	clindamycin 2% cream intravaginally, at night, initially for 14 days
	OR
1	phenoxymethylpenicillin 250 mg orally, 6-hourly initially for 10 days.

 

If persistent, seek expert advice. There is currently no consensus on how to best treat this uncommon condition.

Genital warts (human papillomavirus infection)

Human papillomavirus (HPV) infection causes 4 different but related abnormalities in the human female genital tract:

·            Genital warts are most commonly caused by HPV types 6 and 11. Like all sexually active women, those with genital warts or sexual partners also infected should have regular Papanicolaou (Pap) smears.

·            Low grade cervical dysplasia is caused by both oncogenic and nononcogenic HPV types.

·            High grade dysplasia, which is the premalignant lesion, is only associated with infection by oncogenic viruses.

·            Cervical cancer is most commonly caused by HPV types 16 and 18, and strongly associated with various other oncogenic HPV types. This gives the HPV type an importance over and above the acute infective episode (which is usually transient, asymptomatic and detectable only by cellular changes seen by the Pap smear, at colposcopy or by HPV-DNA testing). The use of HPV-DNA testing in guiding management is being evaluated, but not yet routinely recommended.

 

HPV infection of the male genitalia, in addition to causing genital warts, is uncommonly associated with intraepithelial neoplasia of the penis.

Genital warts are often a recurring problem. In most cases they are trivial, but they can be very extensive and disabling. Patients often complain of some degree of discomfort from the lesions, but it may simply be their appearance and connotations that concern the patient. The concept that the presence of the wart virus infection can cause vulvitis or vulval pain is erroneous. Most condylomatous lesions eventually resolve spontaneously. The exact infectivity and period of latency of HPV have not been determined. Most HPV infections are transient, although it may be that the virus can be reactivated after years of dormancy.

Prior to undertaking therapy for genital warts, it is important to counsel the patient, explaining how the virus is acquired, the long-term prognosis and the association with neoplasia. Because of the possible latency of the virus and the fact that viral DNA may remain long term in the nucleus of human cells, the wearing of condoms will not necessarily protect the patient from re-infection, and if the patient is in a stable relationship it is likely that the partner has been exposed and will also not benefit from this measure. Also, the latency of the virus often makes it impossible to say from which sexual partner the virus was acquired. Needless blame in the patient’s present relationship may result, and this needs to be explained. Patients with HPV often experience feelings of shame and guilt that need to be addressed.

Patients with genital warts may have been exposed to other sexually transmissible infections (STIs) and the need for an STI screen should be discussed with the patient. Concomitant infection(s) should be treated. Specialist advice or referral may be needed.

External genital warts may be removed by chemical or physical means (including cryocautery or electrocautery), or by patient-applied preparations (imiquimod 5% or podophyllotoxin 0.5%). The preparations described below should be applied with care, as erythema or ulceration can follow contact with normal skin.

For small numbers of readily accessible lesions, use

1	periodic cryotherapy until resolved
	AND/OR
2	podophyllotoxin 0.15% cream or 0.5% paint topically applied by the patient to each wart, twice daily for 3 days followed by a 4-day break (repeat weekly for 4 to 6 cycles until the warts disappear)
	OR
3	imiquimod 5% cream topically applied by the patient to each wart, 3 times per week at bedtime (wash off after 6 to 10 hours) until warts are cleared (usually 12 to 24 weeks)
	OR
4	podophyllum 25% solution in compound benzoin tincture topically applied by the clinician to each wart, wash off after 6 hours (repeat once weekly until the warts disappear).

 

Do not use podophyllotoxin or podophyllum in pregnant or breastfeeding women. Imiquimod is category B1 in pregnancy but there is insufficient data on safety in breastfeeding.

Irritation, if present, is managed with

hydrocortisone 1% cream applied 3 times daily.

 

Treatment of coincident dermatitis or vaginitis will make the warts less liable to become irritable. Female patients should have a two-yearly Pap smear because of the association of genital warts with oncogenic HPVs causing carcinoma of the cervix.

Genital herpes simplex virus infection

 

 

Herpes simplex is the commonest cause of genital ulceration in Australia. It presents as recurrent painful blisters on the genital area that rapidly erode to leave ulcers that heal spontaneously over a 2-week period. Lesions may be unilateral or bilateral and may occur elsewhere on the surrounding skin, as well as on the buttocks and legs. Genital herpes is sexually-acquired. The initial attack is the most severe. Recurrences may be infrequent, but frequent attacks become disabling in some patients. Genital herpes only causes chronic genital lesions, such as persistent ulceration, in immunosuppressed patients.

Patients should have a full STI screen including HIV serology on their first presentation. Current therapy is not curative but specific antivirals may shorten the episode if commenced in the first 72 hours of symptoms.

After taking a swab for culture, direct immunofluorescence or polymerase chain reaction (PCR), use

1	valaciclovir 500 mg orally, 12-hourly for 5 days
	OR
2	aciclovir 400 mg orally, 8-hourly for 5 days (preferred in pregnancy, seek expert advice)
	OR
3	famciclovir 125 mg orally, 12-hourly for 5 days.

 

Longer treatment may be needed in severe disease.

 

Infrequent but severe recurrences can be treated with episodic therapy, commencing at the onset of prodromal symptoms.

1	valaciclovir 500 mg orally, 12-hourly for 3 days
	OR
2	famciclovir 125 mg orally, 12-hourly for 5 days
	OR
3	aciclovir 400 mg orally, 8-hourly for 5 days (preferred in pregnancy, seek expert advice).

 

This may be indicated for frequent, severe recurrences. Suppression reduces recurrences by 70% to 80% but transmission may still occur.

1	valaciclovir 500 mg orally, daily for up to 6 months
	OR
2	aciclovir 200 mg orally, 12-hourly for up to 6 months (preferred in pregnancy, seek expert advice)
	OR
3	famciclovir 250 mg orally, 12-hourly, for up to 6 months.

 

If there is breakthrough during prophylaxis higher doses may be successful.

Treatment should be interrupted every 6 months to determine the natural history of the disease in any given patient, but may be restarted in the event of recurrence.

Pruritus ani

Pruritus ani (itching of the perianal area) is a symptom, not a disease, and there is often more than one cause. The clinical presentation is often nonspecific with erythema, excoriation and fissuring seen in acute exacerbations and lichenification developing in longstanding cases.

Consider the following in the aetiology of this condition:

·            threadworms

·            contact dermatitis from the use of agents such as soaps, cosmetics, contraceptive agents

·            dermatoses, eg dermatitis, psoriasis, tinea, and particularly seborrhoeic dermatitis

·            anal and rectal pathology, eg fissure, fistula, prolapsing haemorrhoids, carcinoma

·            Candida albicans infection

·            maceration associated with obesity, sweating, tight clothing, sanitary and incontinence underwear

·            stress (possibly an aggravating factor).

 

In practice, the majority of males and females with this symptom have either dermatitis or psoriasis. Infective causes are very uncommon. However, more serious conditions such as squamous cell carcinoma, extramammary Paget’s disease and Crohn’s disease can present in this way.

Rule out superinfection by bacterial skin swabs and fungal scrapings. Instruct patient to use a soap substitute (eg emulsifying ointment) and wear loose-fitting cotton underwear.

Treat any underlying cause that is found.

If a treatable cause cannot be found and the above simple measures do not resolve the problem, treatment with a topical corticosteroid is usually required. Short-term use of methylprednisolone aceponate 0.1% in a fatty ointment base is usually adequate but, if the area is severely lichenified, treatment may need to be continued for 4 to 6 weeks for adequate resolution. When symptoms have settled, reduce to 1% hydrortisone ointment for maintenance therapy as needed.

Management in patients who fail to respond to initial treatment can be very complex and contact allergic dermatitis or contact irritant dermatitis may develop if multiple agents are used. Early consultation with a dermatologist is recommended.

If initial treatment is successful, the patient should continue to use general measures, above, and a bland lubricant such as sorbolene cream, daily. If the diagnosis is psoriasis, use a weak tar cream such as 2% liquor picis carbonis (LPC) in aqueous cream daily as a preventive measure.

If the condition recurs, the patient can repeat treatment with methylprednisolone aceponate until in remission again. When symptom control is achieved the patient may return to maintenance therapy with hydrocortisone or tar.

 Genital skin diseases in prepubertal girls

 

Genital skin disease is less common in children than adults, and girls are more susceptible than boys. Most skin diseases that occur in this age group also occur in adults, and therapy is essentially the same; however, it is important to understand that vulvovaginal candidiasis does not occur in prepubertal girls. Two relatively common vulvovaginal conditions are seen only in children: fusion of the labia minora, and group A streptococcal vulvovaginitis (see Streptococcal perianal dermatitis, vulvitis and balanitis in children).

Genital dermatitis in prepubertal girls

Most cases of genital dermatitis in girls occur in atopic children. However, irritant dermatitis may occur in the setting of faecal or urinary incontinence, wearing of night nappies, continuous application of unnecessary medications (such as imidazole creams for misdiagnosed Candida) and overuse of bubble baths and soap. Much has been made in the literature of ‘poor hygiene’ as a cause of genital dermatitis but in practice this is not common.

Genital dermatitis in children presents with itch, and erythema and rugosity of the labia majora.

As in adults, the first step in management is avoidance of irritants. In children these are usually bubble bath, soap, nylon underwear, lycra dancing and sporting clothes, wearing of wet swimming costumes, and antifungal creams. If the child is incontinent, particularly from chronic constipation (which is common), this should be addressed as should the wearing of nappies at night. A single dose of pyrantel embonate suspension (according to manufacturer’s instructions) should be administered to rule out pinworm infestation as a cause of itching.

Exclude superinfection, by bacterial culture of skin. It is not necessary to seek Candida infection, or perform vaginal swabs or urine examination.

Avoid the following: soap, excessive washing and bubble bath (use a soap substitute instead; wiping back to front; and tight occlusive clothing. Advise weight reduction in obese individuals. Eliminate irritants and allergens. Address incontinence issues. Use

a bland emollient topically, 3 times daily PLUS hydrocortisone 1% topically, daily for 2 weeks. Then cease, but be ready to re-use at the first sign of itching.

 

If there is no improvement in 2 weeks, refer the patient to a dermatologist.

Vulval psoriasis in children

 

Although less common than dermatitis, psoriasis is often a cause of persistent genital and perianal rashes in children. The usual presentation is with a symmetrical nonscaly, well-demarcated rash involving the labia majora, perineum, perianal skin and sometimes the natal cleft. Often the rash is resistant to treatment with 1% hydrocortisone, and many cases of ‘treatment-resistant’ dermatitis are in fact psoriasis. As in adults, there may be signs of psoriasis elsewhere that may have gone unnoticed (eg nail pits and scalp scaling).

Take skin swabs to rule out superinfection and treat according to findings. It is not necessary to take vaginal swabs or urine culture.

Commence therapy with

methylprednisolone 0.1% in a fatty ointment base topically, daily. Continue until rash is resolved (this may take several weeks).

 

Then attempt to introduce a tar preparation, commencing with

liquor picis carbonis (LPC)[Note 1] 2% in aqueous cream topically, twice daily.

 

If LPC is not tolerated, attempt therapy with ichthammol 2% in aqueous cream.

If tar is not tolerated, or it is difficult to achieve control, refer to a dermatologist.

 

Lichen sclerosus in prepubertal girls

 

Lichen sclerosus is very uncommon in children, but is a significant cause of morbidity. The appearance of the rash is a white plaque encircling the vulva, perineum and perianal skin. It does not involve the vagina. Telangiectasias and haemorrhagic blisters may occur, and these may bleed. In addition to itching, which is a typical adult complaint with this condition, constipation and urinary tract symptoms may occur. Children are therefore often investigated for bowel and urinary tract abnormality, and because of the unusual clinical appearance and bleeding it is common for child sexual abuse to be reported. If left untreated in children, significant atrophy of the labia minora may occur and eventually scarring may cause the clitoris to be buried.

Skin biopsy is traumatic in children and is not usually necessary because of the characteristic clinical appearance and lack of differential diagnosis of white plaque in this age group.

Treatment of lichen sclerosus in children is complex, involves the use of potent corticosteroids on the genitalia, similar to the regimen used in adults. Treatment must be carefully monitored and individualised. In addition there may be alleged child sexual abuse issues that have to be resolved Referral to, or advice from, a dermatologist is recommended before initiating therapy.

Prolonged remission may be achieved in children and maintenance therapy is not always required; however, ongoing follow-up is necessary. The disease may reactivate at any stage, and even if asymptomatic, ongoing loss of structure may occur.

Genital warts and genital herpes in prepubertal children

 

Genital warts and genital herpes have the same appearance in children as in adults, and in a child should always raise the issue of possible child sexual abuse or, in the very young child, vertical transmission. If unsure of the diagnosis, refer to a dermatologist. If the diagnosis is definite, the child should be referred to a child protection unit. Suspected child sexual abuse must be notified.

For treatment of genital warts, see adult treatment. Physical therapies such as cryotherapy are unsuitable for treating genital warts in children unless performed under general anaesthetic.

For treatment of genital herpes in children, use

aciclovir 10 mg/kg up to 400 mg orally, 8-hourly.

Genital skin diseases in the male

 

Genital skin disease in males and females shares many features in common clinically and in terms of treatment.

 

	common	uncommon	rare
prepubertal males	dermatitis, psoriasis, molluscum contagiosum	streptococcal balanitis, staphylococcal balanitis, perianal dermatitis, scabies, genital warts, genital herpes, naevi	lichen sclerosus (uncircumcised males), idiopathic scrotal oedema
postpubertal males	dermatitis (seborrhoeic, irritant, allergic, atopic), psoriasis, tinea, genital warts, genital herpes, sebaceous cysts, pearly penile papules, pubic lice, molluscum contagiosum	balanitis (candidal, streptococcal, staphylococcal), lichen planus, scrotal pain syndromes (scrotodynia), hidradenitis suppurativa, scrotal angiokeratomas, seborrhoeic keratoses, sexually transmissible infections, scabies	lichen sclerosus (uncircumcised males), plasma cell balanitis, fixed drug eruption, squamous cell carcinoma, basal cell carcinoma, melanoma, extramammary Paget’s disease, recurrent erythema multiforme, Reiter’s syndrome, Behçet’s syndrome, idiopathic calcinosis of the scrotum

Genital dermatitis and psoriasis in males

 

In males, genital dermatitis and psoriasis are common, and the presentation is the same as in females, the distribution being the scrotum and inguinal folds. Endogenous dermatitis (seborrhoeic and atopic) usually does not involve the penis; however, allergic dermatitis will involve any area where contact has been made with the allergen. In males, the allergen may not have been directly applied to the penis, but may have been inadvertently transferred from the fingers. For management, see general management of genital dermatitis in females.

Psoriasis may involve the penis and the glans. Management is the same as in females.

Pruritus ani

 

Pruritus ani (itching of the perianal area) is a symptom, not a disease, and there is often more than one cause. The clinical presentation is often nonspecific with erythema, excoriation and fissuring seen in acute exacerbations and lichenification developing in longstanding cases.

Consider the following in the aetiology of this condition:

·            threadworms

·            contact dermatitis from the use of agents such as soaps, cosmetics, contraceptive agents

·            dermatoses, eg dermatitis, psoriasis, tinea, and particularly seborrhoeic dermatitis

·            anal and rectal pathology, eg fissure, fistula, prolapsing haemorrhoids, carcinoma

·            Candida albicans infection

·            maceration associated with obesity, sweating, tight clothing, sanitary and incontinence underwear

·            stress (possibly an aggravating factor).

 

In practice, the majority of males and females with this symptom have either dermatitis or psoriasis. Infective causes are very uncommon. However, more serious conditions such as squamous cell carcinoma, extramammary Paget’s disease and Crohn’s disease can present in this way.

Rule out superinfection by bacterial skin swabs and fungal scrapings. Instruct patient to use a soap substitute (eg emulsifying ointment) and wear loose-fitting cotton underwear.

Treat any underlying cause that is found.

If a treatable cause cannot be found and the above simple measures do not resolve the problem, treatment with a topical corticosteroid is usually required. Short-term use of methylprednisolone aceponate 0.1% in a fatty ointment base is usually adequate but, if the area is severely lichenified, treatment may need to be continued for 4 to 6 weeks for adequate resolution. When symptoms have settled, reduce to 1% hydrortisone ointment for maintenance therapy as needed.

Management in patients who fail to respond to initial treatment can be very complex and contact allergic dermatitis or contact irritant dermatitis may develop if multiple agents are used. Early consultation with a dermatologist is recommended.

If initial treatment is successful, the patient should continue to use general measures, above, and a bland lubricant such as sorbolene cream, daily. If the diagnosis is psoriasis, use a weak tar cream such as 2% liquor picis carbonis (LPC) in aqueous cream daily as a preventive measure.

If the condition recurs, the patient can repeat treatment with methylprednisolone aceponate until in remission again. When symptom control is achieved the patient may return to maintenance therapy with hydrocortisone or tar.

 

Balanitis

 

Inflammation of the glans penis is rare in circumcised males and should be referred for specialist advice. In prepubertal boys, Streptococcus pyogenes is commonly cultured from skin swabs taken when the foreskin is retracted. In adults, bacterial causes are less common than Candida albicans.

If Streptococcus pyogenes is cultured, use

phenoxymethylpenicillin (child: 10 mg/kg up to) 500 mg orally, 6-hourly for 10 days.

 

Candidal balanitis occurs typically in a sexually active uncircumcised male, who presents with itching, red, maculopapular lesions of the glans penis, with circumferential scale and satellite lesions. Take swabs to confirm the diagnosis. The female partner may have vaginal candidiasis but usually does not.

Drying under the foreskin after showering is recommended. A combination of an anticandidal agent and hydrocortisone is usually successful. Use

1	clotrimazole 1% +hydrocortisone  1% topically, applied twice daily
	OR
1	miconazole 2% + hydrocortisone 1% topically, applied twice daily.

 

Continue treatment for 2 weeks after symptoms resolve.

Some patients respond better to ointments, which offer the added benefit of ‘waterproofing’ the area. The only anticandidal preparation available in ointment form is nystatin. Use

	hydrocortisone 1% ointment topically, twice daily
	PLUS
	nystatin 100 000 units/g ointment topically, twice daily.

 

If the female partner is a candida carrier, either symptomatic or asymptomatic, treat as for chronic vulvovaginal candidiasis.

Some patients get recurrent relapsing candidal balanitis, reflecting either a carrier state or sensitivity to their partner’s commensal levels of Candida albicans; consider circumcision in these cases.

 

Consider noninfectious balanitis when there has been no response to antibiotic or antifungal treatment, even where there was positive microbiology.

First-line treatment should include use of a soap substitute, attention to personal hygeine and use of a bland emollient. If this is unsuccessful, consider a dermatosis such as psoriasis, lichen planus, plasma cell balanitis, fixed drug eruption or squamous cell carcinoma in situ. These are difficult conditions to diagnose and treat. A skin biopsy is usually required. Referral to a dermatologist is recommended.

Bowen's disease of the penis

Bowen’s disease of the penis is only treated surgically as a last resort. Refer to a dermatologist for discussion of treatment options.

Lichen sclerosus in males

 

Lichen sclerosus is a rare disease in males and is usually confined to the glans penis in uncircumcised individuals. The male to female ratio is 1:10. The appearance is the same as in the female, with a white, sclerotic skin surface sometimes with telangiectasia. Lichen sclerosus is a common cause of phimosis in boys and occasionally in men.

Although circumcision was formerly advocated as the treatment of choice it has now been recognised that the use of potent topical corticosteroids is as successful as in females and should be attempted first (see treatment of lichen sclerosus in females).

Pearly penile papules

 

Pearly penile papules are asymptomatic, skin-coloured, dome-shaped papules on the coronal margin and sulcus. They may be single, or grouped in lines or rings encircling the glans. The patient is often concerned that these lesions are genital warts, but histologically they are angiofibromas. Reassure the patient that the lesions can be considered a normal variant. If they are severe or disfiguring and the patient requests treatment, refer to a dermatologist.

 

 

 

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