Section 3. Diaper Dermatitis and Rashes in the Diaper Area

Diaper dermatitis generally refers to the irritant contact dermatitis that may result from multiple factors in the area: macerated skin (softened by being wet), rubbing and wiping, and possibly the presence of ammonia in urine and proteases and lipases in stool, which cause skin irritation and breakdown. It can become complicated by secondary bacterial or yeast infections as well.

Insight

The so-called “Greek method” of washing the soiled diaper area under a running tap of warm water rather than using abrasive wipes is said to prevent diaper dermatitis.

Synonym Diaper rash, nappy rash.

Epidemiology

Age Most babies develop some form of diaper dermatitis during their diaper wearing years.

Gender M = F.

Prevalence At any one point in time, up to one-third of infants may have diaper dermatitis. The prevalence of severe diaper dermatitis (defined as erythema with ulcerations, oozing papules, and pustules) is 5%.

Etiology Excessive hydration of the skin and frictional injury leads to a compromised skin barrier and irritation from ammonia, feces, cleansing products, fragrances, and possible superinfection with Candida albicans or bacteria.

Season Reportedly highest during winter months, perhaps due to less frequent diaper changing.

Pathophysiology

The warm moist environment inside the diaper and frictional damage decreases the protective barrier function of the skin in the diaper area. Then predisposing factors such as seborrhea, atopic dermatitis, and systemic disease, as well as activating factors such as allergens (in detergents, rubbers, and plastic), primary irritants (ammonia from urine and feces), and infection (by yeast or bacteria) lead to a rash in the diaper area.

Physical Examination

Skin Findings

Type of Lesion Ranges from macular erythema (Fig. 3-1) to papules, plaques, vesicles, erosions, and rarely ulcerated nodules.

Color Ranges from mild erythema to diffuse beefy redness.

Palpation Ranges from nonindurated to prominently elevated lesions.

Distribution Diaper area, convex surfaces involved, folds spared. Severe cases may involve folds and have characteristic C. albicans satellite pustules.

Differential Diagnosis

Diagnosis The diagnosis of diaper dermatitis may be made clinically, although refractory response to conventional treatments should raise the suspicion of less common rashes in the diaper area.

Differential Diagnosis Diaper dermatitis must be differentiated from psoriasis, granuloma gluteale infantum (foreign body reaction, typically to baby powder, or topical steroids), primary candidiasis (perianal or intertriginous involvement with satellite lesions), seborrheic dermatitis, acrodermatitis enteropathica (AE; caused by zinc deficiency), and histiocytosis X.

Course and Prognosis

Most episodes of diaper dermatitis are self-limited with a duration of 3 days or less. Severe cases of diaper dermatitis are usually caused by chronic irritants or secondary infection with candida or bacteria.

Management

The following help is minimizing rashes in the diaper area:

1. 1. Keeping the diaper area clean and dry with gentle cleansing of the area (cotton balls dipped in warm water or nondetergent cleanser) and frequent diaper changes promptly after defecation and urination.

   2. Remove any irritating agent or allergen from the diaper environment; hypoallergenic or cloth diapers may be less irritating.

   3. Exposing the skin to air periodically will help keep it dry.

   4. Protective creams and ointments such as zinc oxide (Desitin, Triple Paste), petrolatum (Hydrolatum, Vaseline), mineral oils, baby oils, lanolin, or vitamins A and D (A&D ointment) may protect the skin from moisture and help heal the infant’s skin.

   5. For severe inflammation, mild topical steroids (2.5% hydrocortisone ointment) may be used sparingly. Since the diaper area is always under occlusion, the steroid effects will be augmented, and baby skin in the groin area is already very sensitive.

   6. Cutaneous candidiasis requires topical antifungal treatment with nystatin or clotrimazole creams. Avoid anticandidal preparations that are mixed with cortisone to prevent steroid side effects in the occluded diaper area.

   7. Bacterial infections may be treated with topical mupirocin; caution is advised with bacitracin and neomycin preparations as the incidence of allergic contact dermatitis is very high. Oral antibiotics may be indicated in severe cases.

   8. Powders (talc, baby powder, cornstarch, magnesium stearate, zinc stearate, and baking soda) can be used to absorb moisture and reduce friction but should be applied carefully so accidental inhalation does not occur.

Psoriasis in Diaper Area

Psoriasis can first manifest itself as a recalcitrant diaper rash, and should be considered if conventional diaper rash remedies are not effective. Other stigmata of early psoriasis include seborrhea, nail pitting, and intergluteal erythema. A family history of psoriasis can also suggest this diagnosis.

Epidemiology

Age Any age, typically seen first in the diaper area of children younger than 2 years.

Gender F > M.

Incidence Uncommon.

Etiology Unclear.

Genetics Possible autosomal dominant inheritance with incomplete penetrance. Associated with HLA B13, HLA B17, HLA Bw16, HLA B37, and HLA Cw6.

Pathophysiology

In normal skin, the cells mature, shed, and are replaced every 3 to 4 weeks. In psoriasis, there is shortening of the cell cycle to 3 to 4 days. This leads to increased epidermal cell turnover with decreased shedding and, hence, the accumulation of dead cells as layers of silvery-white scale.

Physical Examination

Skin Findings

Type Scattered erythematous papules, may coalesce into a well-delineated erythematous plaque.

Color Dark-red plaques, may have a silvery mica-like scale.

Size Pinpoint to several centimeters.

Distribution Anogenital area, may also involve intergluteal cleft, umbilicus, behind or inside the ears, scalp, extremities (Fig. 3-2).

Nails May have pinpoint pits indicative of psoriasis.

Differential Diagnosis

The well-delineated bright-red plaque and silvery mica-like scale is characteristic of psoriasis. Removal of the scale may result in punctate bleeding (Auspitz sign).

Laboratory Examinations

Dermatopathology Epidermal thickening with edema of dermal papillae, thinning of suprapapillary area.

Course and Prognosis

Chronic course with remissions and exacerbations, very unpredictable. Some children progress to mild disease with intermittent exacerbations. Other children have a more severe course with recurrent flares, and 5% develop an associated arthritis.

Management

Psoriasis in the diaper area can be both refractory and/or recurrent.

1. 1. Emollients such as petrolatum, moisturizers, or diaper creams can help minimize flares and reduce itching.

   2. Allowing the diaper area to be exposed to air for short periods can also help reduce the chafing that can exacerbate psoriasis (Koebner phenomenon).

   3. Sunlight exposure is thought to help psoriasis, but sunburns should be avoided.

   4. Topical tar preparations are anti-inflammatory and can be used in the bath water (Balnetar or Polytar) or in creams (MG217 or Elta tar creams). Prolonged use of these agents is not recommended.

   5. More severe cases may require short courses of mild topical steroids (hydrocortisone 2.5%, desonide 0.05% cream or ointment). It is important to use steroid in the diaper area sparingly since the occlusive diaper increases the steroid potency as well as the risk of steroid side effects such as skin thinning and striae.

Candidal Infection

Commonly overlooked, Candida diaper dermatitis should be suspected whenever a diaper rash fails to respond to conventional treatment, especially following a course of systemic antibiotic therapy. The infection is propagated by the chronic occlusive state of diapers worn during infancy.

Synonym Monilial diaper dermatitis.

Epidemiology

Age Any diaper wearing stage (approximately infancy to 3 years of age).

Gender M = F.

Incidence Common.

Etiology C. albicans organisms are harbored in the lower intestinal tract of the infant. Upon defecation, infected feces introduce yeast into area. The moist occlusive diaper environment favors candidal overgrowth and leads to a rash.

Pathophysiology

C. albicans in mouth or GI tract of infant can proliferate in moist diaper environment. Predisposing factors such as systemic antibiotics can also contribute to Candida overgrowth.

History

Candidal overgrowth is seen most frequently following systemic antibiotic therapy. Lesions appear first in the perianal area and then spread to perineum and inguinal creases. The diaper rash may occur in conjunction with oral thrush.

Physical Examination

Skin Findings

Type Erythema with fragile satellite pustules (Fig. 3-3). Rash involving perineum is sharply demarcated with elevated rim and variable scaling along the border. Pinpoint satellite vesicopustules often present.

Color Beefy red erythematous base.

Distribution Genitocrural area, buttocks, lower abdomen, and inner aspects of the thighs, does not spare folds.

Diagnosis and Differential Diagnosis

Diagnosis Observation of beefy red rash with vesicopustular satellite lesions is diagnostic. Scrapings and cultures can be confirmatory.

Differential Diagnosis Primary candidal infection in the diaper area has characteristic satellite papules and pustules that are virtually diagnostic. It may be confused with other recalcitrant rashes in the diaper area such as psoriasis, AE, or histiocytosis X. Most commonly, it can be seen in conjunction with other diaper rashes as a secondary infection.

Laboratory Examinations

Microscopic examination of skin scrapings with potassium hydroxide, Gram stain or periodic acid-Schiff, demonstrate budding yeasts and hyphae or pseudohyphae. Lesions may be cultured on Sabouraud’s or Nickerson’s medium. White mucoid colonies grow within 48 to 72 hours.

Course and Prognosis

Rash progresses until Candida is treated. Area may become eroded and painful.

Management

1. 1. Topical nystatin (Mycostatin) or clotrimazole (Lotrimin) creams tid to area will clear rash. Care should be taken to avoid anticandidal preparations that are mixed with cortisones (Lotrisone, Vytone) since these may be too strong and result in unwanted steroid side effects in the occluded diaper area against baby skin.

   2. Oral nystatin suspension (nystatin swish and swallow, 1 to 3 mL po qid) can be applied to the affected mouth areas to treat oral thrush or gastrointestinal candidal overgrowth. This will also reduce chance of candidal recurrence in the diaper area.

Acrodermatitis Enteropathica

AE is a hereditary or acquired clinical syndrome caused by zinc deficiency. It is characterized by an acral, vesiculobullous eczematous dermatitis characteristically distributed on the face, hands, feet, and anogenital area.

INSIGHT

If Acrodermatitis Enteropathica Is Suspected, an Alkaline Phosphatase Level Can Be Helpful; This Zinc-Dependent Enzyme Is Often Low in Such Patients.

Epidemiology

Age

Hereditary In infants given bovine milk: days to few weeks after birth. In breast-fed infants: soon after weaning.

Acquired Older children and adults with illness that depletes zinc supply.

Gender M = F.

Etiology Hereditary or acquired deficiency in zinc.

Hereditary Autosomal recessively inherited disorder in zinc absorption thought to be secondary to abnormal zinc-binding ligands. Zinc in human milk appears to be more bioavailable to infants than zinc from bovine milk.

Acquired Long-term zinc deficiency can be seen in patients with parenteral nutrition lacking zinc, bowel bypass syndrome, Crohn’s disease, HIV, cystic fibrosis, alcoholism, vegetarian diets, essential fatty acid deficiencies, and other syndromes.

Pathophysiology

Low serum zinc levels in infancy or childhood leads to AE. The basic defect is a GI malabsorption of zinc. Hereditary AE may be secondary to an abnormal zinc-binding ligand. Acquired AE can be seen with any systemic disease with GI malabsorption of zinc. The major function of zinc is to be incorporated into enzymes, and there are more than 200 zinc metalloenzymes in the body.

History

Review of systems may include diarrhea, weight loss, listlessness, and behavioral changes (irritability, crying, and restlessness).

Physical Examination

Skin Findings

Type of Lesion Eczematous or psoriasiform plaques may progress to vesiculobullae or erosions that crust and become dry (Fig. 3-4A and B).

Color Erythematous base.

Distribution Perioral and symmetrically located on buttocks, extensor surfaces (elbows and knees), and acral areas (fingers and toes).

General Findings

Diarrhea, cachexia, alopecia, nail dystrophy, glossitis, stomatitis, hypogeusia (decreased sense of taste), photophobia, drooling, and growth retardation. Hypogonadism in males (more evident in adolescence). Emotional disturbances.

Laboratory Examinations

Low serum zinc (<50 μg/dL) or alkaline phosphatase levels. “Zebra striped” light banding of hair can be seen with polarized light microscopy. However, zinc levels may fluctuate with stress or infection.

Differential Diagnosis

The differential diagnosis includes other bullous diseases (such as linear IgA chronic bullous disease of childhood and bullous impetigo), psoriasis, histiocytosis X, and candidal infection. Refractory diaper dermatitis associated with periorificial and acral findings should lead the clinician to suspect AE.

Course and Prognosis

If unrecognized, AE has a relentlessly progressive course leading to infection and disability. Once recognized and treated, AE manifestations are quickly corrected and reversed.

Treatment

1. 1. Topical zinc creams (Desitin, A&D ointment, zinc oxide paste, and Triple Paste) can begin to improve the rash.

   2. Dietary supplement of zinc gluconate, acetate, or sulfate (5 mg/kg/d divided bid/tid) is usually curative. The RDA (recommended daily allowance) of zinc is 15 mg/d.

   3. In severe cases, ZnCl2 may be administered intravenously.

Granuloma Gluteale Infantum

Granuloma gluteale infantum is a benign rash in the diaper area characterized by reddish-purple granulomatous nodules. The disorder represents a cutaneous response to a foreign body (talc or zirconium), topical steroids, infection (candida), or inflammation.

Synonyms Kaposi sarcoma-like granuloma and granuloma intertriginosum infantum.

Epidemiology

Age Any diaper wearing age, typically birth to 3 years.

Gender M = F.

Incidence Rare.

Etiology Initiating inflammatory process with maceration and secondary infection leads to a granulomatous response.

Pathophysiology

Lesions believed to be a unique benign granulomatous response to a foreign body, inflammation, maceration, and/or secondary infection.

History

Lesions appear in the diaper area several months after treatment of inciting factors. The rash symptoms can range from being asymptomatic to very painful.

Physical Examination

Skin Findings

Type Granulomatous papules and nodules (Fig. 3-5).

Color Reddish-purple.

Size 0.5 to 4.0 cm in diameter.

Distribution Groin, buttocks, lower aspect of abdomen, penis, rarely intertriginous areas of axillae, and/or neck.

Differential Diagnosis

The papular and nodular lesions of granuloma gluteale infantum can appear very worrisome despite their benign nature because similar lesions can also be seen in sarcomas and lymphomas. Similar lesions may be found in Kaposi sarcoma, tuberculosis, syphilis, and deep fungal infections. The diagnosis of granuloma gluteale infantum is often made clinically and can be confirmed by skin biopsy.

Laboratory Examinations

Light and Electron Microscopy Hyperplastic epidermis with inflammatory cells (mostly neutrophils), a parakeratotic stratum corneum, and a dense inflammatory infiltrate throughout the depth of the cutis with hemorrhage, neutrophils, lymphocytes, histiocytes, plasma cells, eosinophils, newly formed capillaries, and giant cells. Lesions of granuloma gluteale infantum lack the masses of patchy accumulations of lymphoma cells seen in lymphomatous disorders. Granuloma gluteale infantum may be differentiated from more severe granulomatous processes by its lack of fibrous proliferative features, spindle cell formations, and mitoses.

Course and Prognosis

Benign. Lesions resolve completely and spontaneously several months after treatment of the primary inciting inflammatory process and/or infection.

Management

Treatment begins with the identification and elimination of the primary inciting inflammatory process and/or infection.

For the nodular lesions:

1. 1. If topical steroids are being used, discontinuing them often leads to resolution of the nodules.

   2. Conversely, if topical steroids are not being used, a short 2-week trial of topical, intralesional, or impregnated steroid tape (Cordran tape) may hasten resolution of these nodules. Close follow-up is necessary because steroids may worsen the condition.

Langerhans Cell Histiocytosis in Diaper Area

Langerhans cell histiocytosis (LCH) is a rare proliferative disorder of the Langerhans cell (a histiocyte that migrates throughout the skin as an antigen-presenting cell). Although the disease is rare, it frequently presents in infancy as a rash in the diaper area. LCH should be considered if a diaper rash is particularly recalcitrant to usual remedies, especially if systemic symptoms are present.

Insight

In refractory diaper dermatitis with petechiae or purpura, Langerhans cell histiocytosis must be excluded.

Synonym Histiocytosis X, Langerhans cell granulomatosis, type II histiocytosis, LCH

Epidemiology

Age Usually in first year of life. Can be seen up to 3 years of age.

Gender M > F in children.

Incidence Extremely rare, 1 per 5 million children annually.

Etiology Unclear.

Genetics Possibly autosomal recessive with reduced penetrance.

Pathophysiology

Unclear. Several proposed mechanisms include a disturbance of intracellular lipid metabolism, a reactive histiocytic response to infection, or a neoplastic process. Some cases may be hereditary. All theories somehow implicate the Langerhans cell as a primary component.

Physical Examination

Skin Findings

Type Begins as erythema and scale and progresses to purpuric papules, nodules, or vesicles (Fig. 3-6).

Color Reddish-brown or purple.

Size Pinpoint to 1 cm.

Distribution Inguinal and perineal areas, axilla, behind ears, and scalp, can be on the trunk.

General Findings

Decreased immunity can lead to increased susceptibility to infections. Severe forms of the disease can have cell infiltrates of the bone, lung, liver, and lymph nodes

Laboratory Examinations

Dermatopathology Skin biopsy will reveal characteristic Langerhans cells, which are diagnostic of a histiocyte proliferative disorder. Langerhans cells can be identified with positive S-100 and CD1a stains, which will be positive, or electron microscopy demonstration of Birbeck granules in the cytoplasm of the histiocytes.

Differential Diagnosis

The initial presentation of histiocytosis X is similar to seborrhea, with an erythematous scaly rash, but histiocytosis X becomes more extensive cutaneously and can have associated systemic disease. A skin biopsy is usually needed to confirm the diagnosis.

Course and Prognosis

Langerhans cell histiocytosis constitutes a spectrum of disease. The highest mortality rate (38%–54%) is seen in the most severe form: Letterer-Siwe disease (associated with fever, anemia, thrombocytopenia, lymphadenopathy, hepatosplenomegaly, and skeletal tumors). Less severe clinical courses are seen with Hand-Schuller-Christian disease (associated with osteolytic defects, diabetes mellitus, and exophthalmos). Eosinophilic granuloma (associated with osteolytic defects and spontaneous fractures) and Hashimoto-Pritzker disease (aka congenital self-healing reticulohistiocytosis; a benign, self-limited entity with skin lesions only) represent the mildest forms.

Management

The diagnosis of Langerhans cell histiocytosis is important to recognize when an ill infant presents with a refractory or recurrent diaper rash. The diagnosis should be entertained and confirmed by skin biopsy at an early age. For localized skin disease, topical corticosteroids, topical antibiotics, PUVA, and topical nitrogen mustard may be used. For noncutaneous lesions, more supportive and aggressive therapies may be needed (see Section 20, “Langerhans Cell Histiocytosis” for more details).