Basics
Description
Atopic dermatitis or eczema is a chronic skin condition characterized by an acute, intermittent pruritic rash. It most commonly begins in infancy or early childhood with an age-specific pattern of skin involvement. Individuals with atopic dermatitis usually have a personal or family history of atopy (e.g., asthma, hay fever, or rhinitis).
Epidemiology
- Common, occurs in nearly 1 in 5 children
- 60% of affected children will develop atopic dermatitis in the 1st year of life and 85% by age 5 years.
- Higher prevalence in Nevada, Utah, Idaho, and East Coast states
- Higher prevalence in urban versus rural areas
- Usually worse in the winter, but flares can occur at any time of year
Risk Factors
Genetics
- Genetic predisposition in affected patients with 30-70% of family members having atopy (allergies, asthma, eczema)
- Mode of inheritance is not well defined and is likely multifactorial.
- Studies show that genetic mutations in the filaggrin gene (FLG) are associated with skin barrier defects and occur in early-onset atopic dermatitis.
Pathophysiology
- Histologic findings depend on the stage of atopic dermatitis (i.e., acute or chronic).
- Atopic dermatitis is a disorder of immune dysregulation with increased T-cell activation and increased cytokine production of interleukin (IL)-4, IL-5, and IL-13, which lead to increased IgE production.
- Acute atopic dermatitis shows spongiosis, a manifestation of intercellular edema that can lead to vesicle formation.
- Mutations in the filaggrin gene (FLG) are associated with abnormal skin barrier function and cause increased transepidermal water loss and increased penetration of allergens.
Etiology
- Etiology of atopic dermatitis is multifactorial, with genetic, environmental, physiologic, and immunologic factors.
- Increased viral (warts and molluscum) and dermatophyte infections seen in atopic patients appear to be related to cytokine-induced suppression of endogenous antimicrobial peptides.
- Patients often have elevated IgE levels and decreased chemotaxis of neutrophils.
Diagnosis
History
- Age of onset
- Location of skin findings
- Pruritus
- Prior treatment
- Bathing habits
- Family history of atopy (allergies)
- Asthma
- Allergic rhinitis
- Exposure to allergens (i.e., change in detergents/soaps, excessive dryness)
Physical Exam
- Acute flares reveal erythematous and scaly maculopapular exudative patches.
- Chronic disease is characterized by hyperpigmentation or hypopigmentation, lichenification, and scaling.
- Age-specific patterns of skin involvement:
- In infancy, atopic dermatitis is widespread, primarily affecting extensor surfaces and also involves the cheeks, forehead, and scalp.
- In childhood, the disease affects the characteristic flexural sites with lichenification. The hands and face can also be involved.
- From adolescence to adulthood, the flexures, neck, hands, and feet are primarily involved.
- Severe atopic dermatitis can present as exfoliative erythroderma with diffuse scaling and erythema.
- Other associated findings include Dennie-Morgan folds (infraorbital folds), pityriasis alba (dry white patches), hyperlinear palms, facial pallor, infraorbital darkening, follicular accentuation, keratosis pilaris (dry, rough hair follicles on extensor surfaces of upper arms and thighs), and ichthyosis.
Diagnostic Tests & Interpretation
Lab
- There are no diagnostic tests for atopic dermatitis.
- Biopsy can be helpful to rule out other skin disorders, such as psoriasis.
- IgE levels can be elevated but need not be checked.
- Bacterial cultures of skin can be obtained to rule out superinfections.
- Rapid fluorescent antibody studies, polymerase chain reaction studies, or viral cultures and Tzanck smear can identify the presence of eczema herpeticum.
Differential Diagnosis
- Tinea corporis
- Severe seborrheic dermatitis
- Contact dermatitis
- Allergic or irritant psoriasis
- Wiskott-Aldrich syndrome
- Langerhans cell histiocytosis
- Acrodermatitis enteropathica
- Scabies
- Xerosis
- Hyper-IgE syndrome
- Metabolic deficiencies
- Carboxylase deficiencies
- Prolidase deficiencies
Treatment
Medication
- Topical steroids
- Mainstay of therapy to control inflammation
- Mid- to high-potency steroids are used during acute flares, with tapering to milder potency steroids when control is achieved.
- Long-term use of steroids can lead to atrophy, telangiectasias, and tachyphylaxis
- Oral antihistamines, such as hydroxyzine or diphenhydramine, may help to decrease itching in selected patients.
- Oral antibiotics
- Indicated when there is superinfection of lesions
- Oral antivirals are indicated in cases of eczema herpeticum.
- Topical calcineurin inhibitors (TCIs)
- Include tacrolimus ointment and pimecrolimus cream
- Approved for use in children 2 years of age and older
- These topical agents act to suppress T-cell function.
- Sun damage can be potentiated, so children who receive these medications should receive instructions for diligent sun protection and sunscreen use.
- Systemic steroids are generally not used because of the chronicity of atopic dermatitis. They are reserved for refractory atopic dermatitis, and if used, it should only be for a short duration.
- Phototherapy with UVB can be used in patients with extensive disease resistant to other therapies.
- Topical barrier repair agents including N-palmitoylethanolamine cream, MAS063DP cream, and various ceramide formulations may be useful adjuncts to therapy.
Additional Therapies
General Measures
- There is no cure for atopic dermatitis.
- Parents must understand that this is a chronic disease with intermittent flares and that control is the aim of treatment.
- Good skin care is critical to maintenance and includes use of mild soaps, frequent use of emollients, and wet wraps.
- Dilute bleach baths (about 1/4 cup per full tub of water or about 1 tsp per gallon of water) can be used as a once- or twice-weekly 10-minute soak to help reduce bacterial skin colonization and risk for recurrent skin infection.
- Avoidance of environmental irritants is recommended. Nail trimming and protective clothing at night to avoid scratching while sleeping is also helpful.
- Vitamin D supplementation has been shown to decrease the severity of atopic dermatitis due to effects on immunomodulation
Ongoing Care
Follow-up Recommendations
Patient Monitoring
- It should be emphasized to parents that atopic dermatitis is a chronic disease and that good skin care is necessary to control disease activity and enhance quality of life.
- To improve compliance with treatment, providers should use therapeutic patient education techniques so parents and patients can manage this chronic disease.
- Address parental concerns about the safety of topical steroids in order to reduce steroid phobia.
Prognosis
Up to 40-50% of children will outgrow their atopic dermatitis after the age of 5 years.
Complications
- Skin infections
- Decreased cell-mediated immunity, decreased chemotaxis, and decreased production of endogenous antimicrobial peptides can result in increased infection (e.g., viral, dermatophyte, bacterial).
- Patients with atopic dermatitis have a high density of Staphylococcus aureus on their skin, and given the fissures and open excoriations, there is a risk of superinfection.
- Eczema herpeticum
- The decreased integrity of the skin can result in widely spread cutaneous infections such as herpes simplex infection, known as Kaposi varicelliform eruption or eczema herpeticum.
- Similar problems can also be seen with coxsackievirus or molluscum contagiosum and used to occur with vaccinia.
- Overuse of topical medications
- Overuse of potent topical steroids can result in hypopigmentation, telangiectasias, atrophy, and striae as well as excess systemic absorption leading to hypothalamic-pituitary axis suppression and growth retardation.
- Pigmentary changes may result from overuse of topical medications; however, the lesions of atopic dermatitis may themselves cause postinflammatory skin color changes independent of topical therapy.
- Early growth delay is not uncommon among children with atopic dermatitis, although later catch-up growth is generally seen. This may be related to various mechanisms including impaired growth hormone release. Growth delay can occur independent of topical steroid exposure.
- Increased prevalence of emotional, behavioral, and psychological issues secondary to sleep disturbance in patients with atopic dermatitis
Additional Reading
- Barbarot S, Bernier C, Deleuran M. Therapeutic patient education in children with atopic dermatitis: position paper on objectives and recommendations. Pediatr Dermatol. 2013;30(2):199-206. [View Abstract]
- Batchelor JM, Grindlay DJ, Williams HC. What's new in atopic eczema? An analysis of systematic reviews published in 2008 and 2009. Clin Exp Dermatol. 2010;35(8):823-827. [View Abstract]
- Bieber T. Mechanisms of disease: atopic dermatitis. N Engl Med. 2008;358(14):1483-1494.
- Garmhausen D, Hagemann T, Bieber T, et al. Characterization of different courses of atopic dermatitis in adolescent and adult patients. Allergy. 2013;68(4):498-506. [View Abstract]
- Krakowski AC, Eichenfield LF, Dohil MA. Management of atopic dermatitis in the pediatric population. Pediatrics. 2008;122(4):812-824. [View Abstract]
- Ong PY, Leung DYM. Immune dysregulation in atopic dermatitis. Curr Allergy Asthma Rep. 2006;6(5):384-389. [View Abstract]
- O'Regan GM, Irvine AD. The role of filaggrin in the atopic diathesis. Clin Exp Allergy. 2010;40(7):965-972. [View Abstract]
- Spergel JM. Epidemiology of atopic dermatitis and atopic march in children. Immunol Allergy Clin North Am. 2010;30(3):269-280. [View Abstract]
Codes
ICD09
- 691.8 Other atopic dermatitis and related conditions
- 690.12 Seborrheic infantile dermatitis
ICD10
- L20.9 Atopic dermatitis, unspecified
- L20.83 Infantile (acute) (chronic) eczema
- L20.89 Other atopic dermatitis
SNOMED
- 24079001 Atopic dermatitis (disorder)
- 402195009 Infantile atopic dermatitis
- 402196005 Childhood atopic dermatitis
FAQ
- Q: Will the child outgrow this?
- A: Up to 40-50% of children will outgrow their atopic dermatitis after age 5 years. In some patients, however, the disease will persist to varying degrees throughout adulthood.
- Q: Will the steroid treatment change my child's skin color?
- A: Skin pigment changes are caused primarily by the lesions of atopic dermatitis, which cause postinflammatory hyper- or hypopigmentation (darkening or lightening), independent of topical therapy. The discoloration will eventually fade but may take weeks or months.
- Q: When atopic dermatitis is controlled, is any treatment necessary?
- A: Excessive dryness can exacerbate or flare disease. Therefore, less frequent use of soaps and frequent use of emollients are recommended.
- Q: Do food hypersensitivities play a role in atopic dermatitis?
- A: This is a debated issue. In general, the majority of patients are probably not adversely affected by foods. However, some individuals, particularly those who are unresponsive to routine therapy, may benefit from screening for food hypersensitivity and a trial of avoidance to any foods that test positive. The most common foods associated with exacerbation when an association can be made are eggs, milk, wheat, soy, peanuts, and fish.