Practice Essentials
Atopic dermatitis (AD) is a chronic, pruritic inflammatory skin condition (see image below) that typically affects the face (cheeks), neck, arms, and legs but usually spares the groin and axillary regions. AD usually starts in early infancy, but also affects a substantial number of adults. AD is commonly associated with elevated levels of immunoglobulin E (IgE). That it is the first disease to present in a series of allergic diseases—including food allergy, asthma, and allergic rhinitis, in order—has given rise to the “atopic march” theory, which suggests that AD is part of a progression that may lead to subsequent allergic disease at other epithelial barrier surfaces.
Atopic dermatitis. Flexural involvement in childhood atopic dermatitis.
See All About Allergies: Be Ready for Spring, a Critical Images slideshow, to help identify a variety of allergens and symptoms.
Signs and symptoms of atopic dermatitis
Incessant pruritus (itchiness) is the only symptom of AD. The disease typically has an intermittent course with flares and remissions occurring, often for unexplained reasons.
Primary physical findings include the following:
Xerosis (dry skin)
Lichenification (thickening of the skin and an increase in skin markings)
Eczematous lesions (skin inflammation)
The eczematous changes and its morphology are seen in different locations, depending on the age of the patient (ie, infant, child, or adult).
The following is a constellation of symptoms and features commonly seen in AD:
Pruritus
Early age of onset
Chronic and relapsing course
IgE reactivity
Peripheral eosinophilia
Staphylococcus aureus superinfection
Personal history of asthma or hay fever or a history of atopic diseases in a first-degree relative
See Clinical Presentation for more detail.
Diagnosis of atopic dermatitis
The following features should be considered in the diagnosis of AD in accordance with the American Academy of Dermatology (AAD) 2014 Guidelines
:
Essential features (must be present) are as follows:
Pruritus
Eczema (acute, subacute, chronic): (1) Typical morphology and age-specific patterns (facial/neck/extensor involvement in children, flexural involvement in any age group, sparing the groin and axillary regions); (2) chronic or relapsing history
Important features (supports the diagnosis) are as follows:
Early age of onset
Atopy: (1) Personal and/or family history; (2) IgE reactivity
Xerosis
Associated features (nonspecific but suggest the diagnosis of AD) are as follows:
Atypical vascular responses (eg, facial pallor, delayed blanch response)
Keratosis pilaris/pityriasis alba/hyperlinear palms/ichthyosis
Ocular/periorbital changes
Other regional findings (eg, perioral changes/periauricular lesions)
Perifollicular accentuation/lichenification/prurigo
Exclusionary conditions (conditions that should be excluded) are as follows:
Scabies
Seborrheic dermatitis
Contact dermatitis
Ichthyoses
Cutaneous T-cell lymphoma
Psoriasis
Photosensitivity dermatoses
Immune deficiency diseases
Erythroderma of other causes
Additional considerations in the diagnosis of AD are as follows:
No reliable biomarker exists for the diagnosis of AD
Laboratory testing is seldom necessary but a complete blood cell count can be useful to exclude immune deficiency; an IgE level can be helpful to confirm an atopic pattern; a swab of skin can be helpful to identify S aureus superinfection
Allergy and radioallergosorbent testing is of little value
Biopsy shows an acute, subacute, or chronic spongiotic dermatitis pattern that is nonspecific but can be helpful to rule out other conditions (eg, cutaneous T-cell lymphoma)
See Workup for more detail.
Management of atopic dermatitis
Agents typically used to treat AD include the following:
Moisturizers: Petrolatum, Aquaphor, or newer agents such as Atopiclair and Mimyx
Topical steroids (current mainstay of treatment; commonly used in conjunction with moisturizers): Hydrocortisone, triamcinolone, or betamethasone; ointment bases are generally preferred, particularly in dry environments
Broad immunomodulators: Tacrolimus and pimecrolimus (calcineurin inhibitors; generally considered second-line therapy)
Targeted biologic therapies: Dupilumab (anti-IL-4Ra monoclonal antibody)
Other treatments that have been tried include the following:
Ultraviolet (UV)-A, UV-B, a combination of both, psoralen plus UV-A (PUVA), or UV-B1 (narrow-band UV-B) therapy
In severe disease, methotrexate, azathioprine, cyclosporine, and mycophenolate mofetil
Everolimus
Probiotics
Antibiotics for clinical infection caused by S aureus or flares of disease
Intranasal mupirocin ointment and diluted bleach (sodium hypochlorite) baths
Nonmedical measures that may be helpful include the following:
Using soft clothing (eg, cotton) next to the skin; wool products should be avoided
Maintaining mild temperatures, particularly at night
Using a humidifier (cool mist) in both winter and summer
Washing clothes in a mild detergent, with no bleach or fabric softener
Avoiding specific foods as appropriate if there is concomitant food allergy
See Treatment and Medication for more detail.