Labial adhesions are a fairly common occurrence, occurring in up to 3% of girls.⁵² These are seen primarily under the age of 3 years.⁵³ These appear as midline fusion of the labia majora, resulting in variable narrowing of the introitus (Fig. 15-3). A survey of 108 girls showed that adhesions were posterior in 79%-93% of affected girls, sometimes with mid or anterior adhesions forming.⁵³ Uncommonly, the vulvar vestibule fuses entirely, covering the urethra (Fig. 15-4). Girls with labial agglutination are usually asymptomatic unless urinary retention or infection occurs behind the adhesions. In a series of 425 girls with labial adhesions, over 82% were asymptomatic, although 4% experienced urinary tract infections
(UTIs).⁵⁴ Occasionally, even incomplete adhesions are bothersome as urine can become partially trapped above the synechiae, with dribbling when the child stands.

The diagnosis is made by the clinical appearance. The smooth, flat surface that overlies the introitus can suggest absence of the vagina, but it is distinguished by the presence of a central thin translucent line of fibrous tissue at the site of fusion.

Synechiae usually occur as a result of mild chronic inflammation of the vulvar skin, resulting from mechanical trauma, infection, or skin disease, including lichen sclerosus or irritant dermatitis (Fig. 15-5). Some have suggested that, because topical estrogen generally lyses labial adhesions, low estrogen levels may play a role in the formation of these adhesions. However, serum levels of estrogen in girls with labial adhesions are the same as those in girls without adhesions. Still, the normal infantile estrogen-deficient (compared to postpubertal girls) vulvar epithelium is thin, easily irritated, and more likely to scar compared to well estrogenized vulvar skin. Vulvar epithelium scars easily in general, and even more so in atrophic prepubertal skin.

Generally, no treatment beyond robust reassurance is required, as adhesions regularly resolve by puberty.

The traditional therapy for complete or symptomatic adhesions is the local application of estrogen cream combined with gentle massage and good hygiene. A survey of the literature shows 50%-90% of those treated with estrogen cream and massage cleared, with recurrence of 30%, and 68%-80% of girls receiving topical corticoids cleared with 23% of recurrences.⁵² Surgical intervention has a success rate of 100% and recurrence of 0.⁵⁵ However, no series divide out the girls with primary adhesions (idiopathic) from those with adhesions due to lichen sclerosus. The use of a topical corticosteroid is crucial for the treatment management of girls with adhesions on the basis of skin disease, especially lichen sclerosus, which can cause permanent scarring of other structures if not treated appropriately.

Most vulvologists treat symptomatic labial adhesion with a superpotent topical corticosteroid ointment (much less irritating than a cream) such as clobetasol propionate 0.05% or betamethasone dipropionate ointment in augmented or optimized vehicle 0.05% applied very, very sparingly twice a day, with monthly follow-up. Those children with skin disease should be maintained on a lower potency corticosteroid ointment such as desonide ointment 0.05% daily or thrice weekly superpotent medication for several weeks beyond lysis of adhesions, or at least through puberty in the case of lichen sclerosus.

Rarely, surgical separation is required because of pain, infection, or urinary retention. In a cooperative child, this can be done using topical anesthesia with lidocaine/prilocaine; the frightened child is best treated under general anesthesia/conscious sedation. A well-lubricated cotton swab sometimes can be used to separate the labia. Estrogen cream or a corticosteroid ointment should be applied daily afterward until healed to prevent reformation of the adhesions. The area should be re-evaluated every few days initially by the clinician to detect early recurrence during healing.

Diaper dermatitis is characterized by red plaques that show various degrees of scaling that may be somewhat obscured by moisture. This is covered by the diaper and sometimes exhibits maceration and erosion when severe. The morphology depends upon what factors are producing the dermatitis.

The most common issue causing diaper dermatitis is irritant contact dermatitis produced by urine and feces held against the skin. This appears as a rash occurring on the more convex surfaces that directly contact urine
and stool, and relative sparing of the skin creases (Figs. 15-6 and 15-7). The perineum, buttocks, mons, and upper thighs are most commonly involved. Sharp margination where the diaper ends can occur. The skin is pink to bright red with a shiny, glazed appearance, occasionally with edema and sometimes even blisters or superficial erosions (Fig. 5-30). Eroded skin is tender and painful, especially when it is in contact with irritating substances such as diarrhea, alcohols, or propylene glycol that is contained in diaper wipes.

A severe form of irritant dermatitis is termed diaper dermatitis of Jacquet, granuloma gluteale infantum, or pseudowarts (see section “Granuloma Gluteale Infantum”). This is characterized by sharply marginated, red nodules, often with overlying erosion that confers an umbilicated appearance. These typically affect the labia majora, perianal skin, and perineum (Figs. 15-8 and 15-9).

Frictional dermatitis is most pronounced on the inner thighs, under the fastening tabs and waistband of the diaper, and on other surfaces that rub against the diaper. It consists of mild erythema and papules that wax and wane and respond quickly to diapering more often so that moisture is minimized.

Intertrigo from moisture and friction occurs within the skinfolds of the diaper area but also can occur in the neck creases, under the axilla, and between the fat rolls on the thighs. A relatively sharp cutoff where the dry skin begins is noted. Affected areas may be oozing, macerated, and red. Superficial sloughing of white hydrated skin is common.

When Candida albicans complicates diaper dermatitis, the infection preferentially affects the skinfolds, with deep, bright erythema showing surrounding peripheral scale (Fig. 15-10). Satellite collarettes or round erosions are characteristic.

The shiny, glazed appearance of buttocks and the coalescing satellite papules and pustules are characteristic
of Candida diaper dermatitis. This is confirmed by microscopic examination, culture, or response to therapy.

Psoriasis is another skin disease that less often contributes to diaper dermatitis, because psoriasis is a skin disease that is precipitated by irritation and injury, as occurs from the irritant diaper dermatitis. Often, psoriasis in the diaper area is unaccompanied, at least initially, by extragenital psoriasis.

The diagnosis of diaper dermatitis is made by the presence of erythema and scale, with or without erosions and maceration in the diaper area.

Specific diseases that preferentially affect the diaper area and can mimic routine diaper dermatitis include acrodermatitis enteropathica and Langerhans cell histiocytosis (see below). Patients with Kawasaki disease typically exhibit accentuation of their rash in the diaper area with desquamation late in the course of their disease.

Diaper dermatitis is multifactorial but primarily irritant contact, sometimes with candidiasis. The irritants include wetness and friction of a diaper over skin exposed to urine and stool. Occasionally, atopic dermatitis or psoriasis plays a role.

The prevention and treatment of diaper dermatitis is primarily aimed at changing the environment to eliminate common irritants and re-evaluating the dermatitis that remains. With the advent of gel-containing disposable diapers, diaper rashes have become much less problematic. For the past 30-40 years, these disposable diapers have been the preferred option for diapering infants and toddlers. Disposable diapers were advertised as more convenient, hygienic, and less likely to cause diaper dermatitis than a cotton diaper with a vinyl or rubber pant covering. This cotton core and vapor impermeable outer layer was a set up for causing irritant contact dermatitis and many families gladly welcomed a readily disposable solution. However, the cost is high, and diapers can be left on for prolonged periods. In the last 15 years, cloth diapers have received a makeover to create a modern reusable option that can be cost effective, less likely to produce diaper rash than traditional cloth diapers, and more environmentally conscious. Data regarding comparisons between disposable diapers and current reusable diapers in regard to the frequency of diaper rash are generally lacking. There are suggestions that disposable diapers are superior, but all cloth diapers are not identical, nor are all disposable diapers.⁵⁶ There are a number of reports of increased numbers of infants with severe papulo-erosive Jacquet diaper dermatitis in those using reusable diapers, however.^57,58

In addition to high-quality diapers and frequent diaper changes, the application of barrier cream to the involved areas is useful to protect from urine and feces, and supplying lipids to the epidermis; these should be applied at least twice weekly to the healthy diaper area.⁵⁹ When diaper dermatitis is present, large amounts should be applied to the skin with each diaper change, and avoidance of further irritation from cleansing soaps and some diaper wipes. Most wipes are not problematic.⁵⁹ However, care should be taken to ensure that the pH is appropriate to counteract the alkaline effects of faces and urine and maintain the slight acidity of the area, and that the chosen wipes are free of potential irritants such as alcohol, nonallergy screened fragrances, essential oils, soap, suboptimal surfactants, and harsh detergents (eg, sodium lauryl sulfate).⁵⁹ Allergens to be avoided include methylisothiazolinone (MI), methylchloroisothiazolinone (MCI), bronopol (2-bromo-2-nitropropane-1,3-diol), and iodopropynyl butylcarbamate.⁵⁹ Or, Water Wipes can be used. These contain only water and a trivial amount of grapeseed oil. These lack pH adjustment and antibacterial agents, but studies have shown wipes to be equivalent to washcloths, which also lack these features, and both avoid the potential irritating additives.

However, adherent stool is best removed by gently rinsing the perianal area with warm water and patting the skin dry. The application of a barrier cream to anogenital skin is more effective than the aggressive removal of feces by rubbing or the use of harsh cleansers. Mild corticosteroid preparations such as 1% or 2.5% hydrocortisone ointment (not cream) hastens resolution of inflammation when applied twice daily and covered with barrier cream or ointment. Potent corticosteroids should not be applied under diaper occlusion, which enhances the effect of the medication. Adrenal suppression and deaths due to immunosuppression have been reported in several infants treated with ultra potent corticosteroids under
diaper occlusion.⁶⁰ Anticandidal agents should be added if there is a question of yeast. Nystatin is available in an ointment base and is less irritating than the azole creams. When disease is severe and erosions are present, antifungal medication should be administered orally until healing begins.

Persistence of dermatitis when these measures are taken usually indicates an ongoing irritant process or an alternative diagnosis. Chronic diarrhea is a common cause for persistence of dermatitis, and this predisposes to yeast. An evaluation of the child’s diet and growth parameters and a search for underlying disease such as infection or malabsorption are indicated. In the absence of diarrhea, a skin biopsy may be helpful to identify other primary cutaneous disease.

Perianal streptococcal dermatitis typically occurs in 3- to 5-year-old children, and it is more common in boys than in girls. Most often, 2 to 3 cm of erythema extends outward around the anus with minimal induration (Figs. 15-16, 15-17, 15-18). In other individuals, this erythema is accompanied by painful anal fissuring and a mucoid discharge that makes defecation painful. Constipation and withholding of stool are common, and it is often unclear whether the fissure was produced by the primary disease or by passage of hard stool. Finally, well-demarcated, scaly, beefy red, crusted dermatitis with maceration of the anal verge can occur. In addition, induration of the perianal skin
and satellite-crusted plaques can be seen. Bleeding from the area is common. Girls can exhibit vulvar and vaginal involvement, and boys can experience penile involvement.

In all forms of anogenital bacterial dermatitis, pruritus, excoriations, and lichenification from scratching and rubbing are common. These superimposed eczematous changes can delay the diagnosis.

The diagnosis of perianal bacterial dermatitis is made on clinical grounds and is confirmed by a routine culture that yields Streptococcus, most often group A β-hemolytic Streptococcus and sometimes group B β-hemolytic Streptococcus. It is important to ask the laboratory to culture for these organisms because many laboratories select for enteric pathogens from perianal swabs.

The differential diagnosis of perianal bacterial dermatitis includes pinworm infestation, irritant or Candida dermatitis, atopic dermatitis, psoriasis, inflammatory bowel disease, and sexual abuse. Scratching and rubbing of the skin resulting from pruritus are common and can confuse the diagnosis. All perianal dermatitis should be cultured to rule out a bacterial component.

Bacterial skin infection of the perianal skin, nearly always with group A and sometimes group B β-hemolytic Streptococcus, produces this distinctive dermatitis in children. Many patients diagnosed with perianal streptococcus have throat cultures positive for the organism without symptoms of pharyngitis. Presumably, digital contamination of the anus from the infected pharynx or other body site is the source of the infection.

The treatment of choice for perianal bacterial dermatitis consists of oral antibiotic therapy with concomitant mupirocin ointment several times a day. Beta-lactamase-resistant antibiotics, such as cephalosporines, amoxicillinclavulanate, macrolides and clindamycin, appear to be less associated with recurrence than penicillin and amoxicillin, which have about a 32% recurrence rate.^61,62 Because recurrences are common, some clinicians support antibiotic therapy for as long as 21 days to allow for the skin to heal before discontinuation of medication. Mupirocin ointment applied two to four times a day may minimize recurrences as well. Stool softeners can be useful in children with painful defecation due to perianal inflammation and fissures, and hydrocortisone 1% or 2.5% ointment can minimize pain while awaiting improvement with the antibiotic.

The only symptoms of a pinworm infestation usually are dermatitis and pruritus of the perianal skin and/or vulva. Excoriations are often more prominent than obvious redness and scaling. Complaints of nighttime pruritus are the greatest complaint and may be severe enough to wake the child. Occasionally, a child describes pain rather than itching. Uncommonly, the worms migrate to the vagina in girls and cause vulvar dermatitis and a vaginal discharge or produce balanitis in boys. An uncommon complication is involvement of the appendix with pinworms, a cause of concomitant pinworms and abdominal pain.⁶³

The diagnosis of pinworms is made in the setting of an unexplained perianal or vulvar pruritus, with or without a mild dermatitis, and is confirmed by response to therapy. Pinworms are usually difficult to find for diagnostic evaluation. At night, adult worms are occasionally seen on the perineum or in the anal canal when it is gently everted. Eggs can usually be collected using clear tape placed over the anus first thing in the morning before the eggs are disturbed. The eggs can be viewed adherent to the tape as thick-walled, ovoid structures most easily seen by light microscopy under low power.

The differential diagnosis of pinworm infection includes perianal bacterial dermatitis, atopic dermatitis, irritant dermatitis, and candidiasis. The presence of severe nighttime symptoms of perianal pruritus with minimal inflammation can help to distinguish this disorder from other forms of dermatitis.

Pinworm infestation is the most common form of helminth infestation seen in humans and is produced by infestation with Enterobius vermicularis. Pinworms are much common in children than in adults, with more than 20% of school-aged children acquiring this ubiquitous infestation.

Pinworm infestation begins by ingestion of eggs, usually on fingers that have contacted perianal skin or dirt with eggs. Eggs hatch in the duodenum and mature during passage through the intestines. Migration to the perianal skin occurs, and gravid females deposit their eggs on the anal verge, causing pruritus. Four to six hours after the eggs are deposited, they become infectious, and when the eggs are swallowed, the cycle begins again.

Time honored treatment of pinworms has been with mebendazole 100 mg in a single dose, and application of a mild topical steroid ointment for any dermatitis that is present. For unexplained reasons, mebendazole is no longer available commercially, but it can be obtained through compounding pharmacies. Pyrantel pamoate, in a single dose of 11 mg/kg, can also be used. Treatment of adults and children with albendazole is 400 mg orally, repeated once in 2 weeks.

Multiple family members are often affected at the same time, necessitating widespread simultaneous treatment to cure the infestation. Reinfection is common in schoolaged children.

Retreatment in 2-3 weeks is recommended because medication is ineffective against ova that may have been ingested at the time of the first treatment.

The classic presentation of acrodermatitis enteropathica is a triad of periorificial dermatitis, diarrhea, and alopecia. Infants are irritable and have severe failure to thrive.

The dermatitis consists of periorificial erythematous, well-demarcated, and scaling plaques. At times, the skin may exhibit vesicopustular plaques and crusting (Figs. 15-19 and 15-20). It is most pronounced around the mouth, eyes, and genital area. Neck folds are often involved in infants, and the acral extremities may have similar scaly, erythematous, well-marginated plaques, especially in older children and adults. The diaper dermatitis is usually severe and refractory to standard therapy. Secondary infections with Staphylococcus and Candida are common. Nail dystrophy and paronychia are also common, as is stomatitis.

The diagnosis of acrodermatitis enteropathica is suspected based on the classical triad of dermatitis in a periorificial and acral distribution, alopecia, and diarrhea, and it is confirmed by low serum levels of zinc, alkaline phosphatase, and lipids. A skin biopsy is characteristic but not diagnostic; the upper part of the epidermis appears pale because of the presence of clear cells with balloonlike cytoplasm and loss of normal basophilia in early lesions. Subcorneal vesicles may be present in the upper epidermis, and there is diffuse parakeratosis. Hyperplasia of the epidermis and parakeratosis are seen in older lesions in a nonspecific pattern.

Severe cases of seborrheic dermatitis or psoriasis, especially those complicated by superinfection with Candida, can have a similar appearance, but accompanying extragenital skin is often pathognomonic. The presence of scalp dermatitis suggests seborrhea, and normal laboratory findings rule out acrodermatitis enteropathica.

Acrodermatitis enteropathica is the classic manifestation of zinc deficiency. There are two pathways, both involving inherited mutations of zinc transporters; one is a transient neonatal zinc deficiency, the other is classic acrodermatitis enteropathica.⁶⁴ However, the skin findings can occur also in acquired nutritional deficiency states. All patients with acrodermatitis enteropathica have low levels of plasma zinc and other zinc-dependent metalloproteins such as alkaline phosphatase.

Symptoms of acrodermatitis enteropathica usually do not appear in breast-fed infants until weaning. A zinc-binding ligand that may be absent from the newborn’s intestine appears to be present in breast milk, thus accounting for this observation.

Similar acral dermatitis is seen in other nutritionaldeficiency states including biotin, protein, and essential fatty acid deficiency. These occur with cystic fibrosis, short bowel syndrome, anorexia nervosa, chronic illness, and Crohn disease. Organic acidemias also produce these skin findings, including maple syrup urine disease, methylmalonic acidemia, and phenylketonuria. When screening for zinc deficiency is normal, serum metabolic screening can differentiate among these diseases. In Middle Eastern adolescents, the defect develops as a result of ingestion of high quantities of phytate, which binds zinc and prevents intestinal absorption.

Treatment for acrodermatitis enteropathica consists of supplementation of zinc. Oral supplementation using zinc gluconate, acetate, or sulfate in doses of 5 mg/kg/d is recommended. Symptoms improve within 1-2 days of supplementation, and a response is noted in the dermatitis by 3-4 days. Hair growth begins in 2-4 weeks. After resolution of the disease symptoms, supplementation should be continued in the inherited form of the disease, with measurement of serum zinc levels once or twice yearly. The acrodermatitislike eruptions produced by other nutritional deficiencies are managed by identification of the cause of the deficiencies, and correction of these, just as the therapy of each metabolic disorders, requires its unique management.

Letterer-Siwe disease usually manifests in children aged 2 years or younger and affects internal structures as well as skin. Skin features are the presenting signs in most children, and systemic manifestations typically occur in weeks to months after the onset of the cutaneous disease.

Affected infants develop an erythematous, scaly rash on the scalp that mimicks seborrheic dermatitis. This also affects the intertriginous areas, including the inguinal creases and diaper area. Unlike seborrheic dermatitis or other inflammatory genital skin rashes, the scaling papules are infiltrated and firm (Fig. 15-21). The posterior auricular area and axilla are generally affected as well. Moist scale and crust often cover the papules, but the reddish brown or purpuric nature of the lesions can usually be appreciated. Ulcerations are common and may be present on the oral mucous membranes. Purpuric nodules on the palms and soles are a poor prognostic sign.

Letterer-Siwe disease is a systemic process, with dissemination of abnormal Langerhans cells into the skin and extracutaneous locations including the liver, bone marrow, lymph nodes, and central nervous system. This fulminant process can be fatal, even with early treatment.
Infiltration into the pituitary gland can lead to diabetes insipidus, and orbital infiltrates produce exophthalmos. Fever, anemia, thrombocytopenia, hepatosplenomegaly, and adenopathy are typical. Bony tumors may be hard to appreciate clinically. Some infants have a typical histologic appearance and never develop extracutaneous manifestations. These patients retrospectively have what is called self-healing reticulohistiocytosis.

The prognosis depends on the age of onset, the duration of symptoms, and the degree of systemic involvement. Onset after 6 months of age, the absence of thrombocytopenia and lung involvement, the lack of extensive systemic involvement, and the lack of purpuric skin lesions are all good prognostic signs.

The diagnosis of Letterer-Siwe disease is made with skin biopsy. Immunohistochemistry and occasionally electron microscopy can be used to confirm the diagnosis.