Atopic dermatitis

Causes

Atopic dermatitis is due to a hypersensitivity reaction (similar to an allergy) in the skin, which leads to long-term swelling and redness (inflammation) of the skin. People with atopic dermititis may lack certain proteins in the skin, which leads to greater sensitivity.

Atopic dermatitis is most common in infants. It may start as early as age 2 to 6 months. Many people outgrow it by early adulthood.

People with atopic dermatitis often have asthma or seasonal allergies. There is often a family history of allergic conditions such as asthma, hay fever, or eczema. People with atopic dermatitis often test positive to allergy skin tests.

However, atopic dermatitis is not caused by allergies. The condition tends to get worse when the person is exposed to certain triggers.

The following can make atopic dermatitis symptoms worse:

• Allergies to pollen, mold, dust mites, or animals
• Cold and dry air in the winter
• Colds or the flu
• Contact with irritants and chemicals
• Contact with rough materials, such as wool
• Dry skin
• Emotions and stress
• Exposure to too much water, such as taking too many baths or showers and swimming too often
• Feeling too hot or too cold, as well as sudden temperature changes
• Fragrances or dyes added to skin lotions or soaps

Symptoms

Typical skin changes may include:

• Blisters with oozing and crusting
• Dry skin all over the body or areas of bumpy skin on the back of the arms and front of the thighs
• Ear discharge or bleeding
• Raw areas of the skin from scratching
• Skin coloring changes -- more or less color than the normal skin tone (See: Skin abnormally dark or light)
• Skin redness or inflammation around the blisters
• Thickened or leather-like areas, called lichenification, which can occur after long-term irritation and scratching

Both the type of rash and where the rash appears can depend on the age of the patient:

• In children younger than age 2, skin lesions begin on the face, scalp, hands, and feet. They are often crusting, bubbling, or oozing rashes that itch.
• In older children and adults, the rash is more commonly seen on the inside of the knees and elbows, as well as the neck, hands, and feet.
• During a severe outbreak, rashes may occur anywhere on the body.

Itching, which is sometimes intense, almost always occurs. Itching may start even before the rash appears. Atopic dermatitis is often called the "itch that rashes" because the itching starts, and then the skin rash appears from the scratching.

Exams and Tests

A physical exam will be done. A skin biopsy can be done to confirm the diagnosis or rule out other causes of dry, itchy skin.

Diagnosis is based on the:

• Appearance of the skin
• Personal and family history

Allergy skin testing may be helpful for people with:

• Hard-to-treat atopic dermatitis
• Other allergy symptoms
• Skin rashes that form only on certain areas of the body after exposure to a specific chemical

Treatment

SKIN CARE AT HOME

Taking care of your skin at home may reduce the need for medications.

Avoid scratching the rash or skin:

• Relieve the itch by using a moisturizer, topical steroid cream, or other prescribed cream and taking antihistamines to reduce severe itching.
• Keep your child's fingernails cut short. Consider light gloves if nighttime scratching is a problem.

Keep the skin moist (called lubricating or moisturizing the skin). Use ointments (such as petroleum jelly), creams, or lotions 2 - 3 times a day. Moisturizers should be free of alcohol, scents, dyes, fragrances, or other chemicals. A humidifier in the home will also help.

Avoid anything that makes your symptoms worse. This may include:

• Foods such as eggs in a very young child (always discuss with your doctor first)
• Irritants such as wool and lanolin
• Strong soaps or detergents, as well as chemicals and solvents
• Sudden changes in body temperature and stress, which may cause sweating and worsen the condition
• Triggers that cause allergy symptoms

When washing or bathing:

• Keep water contact as brief as possible and use gentle body washes and cleansers instead of regular soaps. Short, cooler baths are better then long, hot baths.
• Do not scrub or dry the skin too hard or for too long.
• After bathing, it is important to apply lubricating creams, lotions, or ointment on the skin while it is damp. This will help trap moisture in the skin.

MEDICATIONS

At this time, allergy shots are not used to treat atopic dermatitis, although there is evidence that they may benefit certain adults with atopic dermatitis.

Antihistamines taken by mouth may help with itching or if you have allergies. Often you can buy them without a prescription.

• Some antihistamines can cause sleepiness, but they may help with scratching while sleeping.
• Newer antihistamines cause little or no sleepiness. Some are available over the counter. These medications include fexofenadine (Allegra), loratadine (Claritin, Alavert), and cetirizine (Zyrtec).

Most causes of atopic dermatitis are treated with medications that are placed directly on the skin or scalp (called topical medicines):

• At first, you will probably be prescribed a mild cortisone (or steroid) cream or ointment. If this doesn't work, you may need a stronger steroid medicine. You may need different strengths of steroids for different areas of skin.
• Medicines called topical immunomodulators (TIMs) may be prescribed for anyone over 2 years old. TIMs include tacrolimus (protopic) and pimecrolimus (Elidel). Ask your doctor about concerns over a possible cancer risk with the use of these medicines.
• Creams or ointments that contain coal tar or anthralin may be used for thickened areas.
• Barrier repair creams containing ceramides

Wet-wrap treatment with topical corticosteroids has been shown effective for atopic dermatitis, although it can have side effects such as infection.

Other treatments that may be used include:

• Antibiotic creams or pills if the skin is infected
• Drugs that suppress the immune system, such as cyclosporine, methotrexate, or mycophenolate mofetil
• Phototherapy, a medical treatment in which your skin is carefully exposed to ultraviolet (UV) light

Outlook (Prognosis)

Atopic dermatitis is a long-term condition, but you can control it with treatment, by avoiding irritants, and by keeping the skin well-moisturized.

In children, the condition often clears beginning at around age 5 - 6, but flare-ups will often occur. In adults, it is generally a long-term or returning condition.

Atopic dermatitis may be harder to control if it:

• Began at an early age
• Involves a large amount of the body
• Occurs along with allergic rhinitis and asthma
• Occurs in someone with a family history of eczema

Possible Complications

• Infections of the skin caused by bacteria, fungi, or viruses
• Permanent scars

When to Contact a Medical Professional

Call for an appointment with your health care provider if:

• Atopic dermatitis does not respond to moisturizers or avoiding allergens
• Symptoms get worse or treatment does not work
• You have signs of infection (such as fever, redness, or pain)

Prevention

Studies have shown that children who are breast-fed until age 4 months are less likely to get atopic dermatitis.

If the child is not breast-fed, using a formula that contains processed cow milk protein (called partially hydrolyzed formula) may decrease the chances of developing atopic dermatitis.

Alternative Names

Infantile eczema; Dermatitis - atopic; Eczema

References

Excema and hand dermatitis. In: Habif TP, ed. Clinical Dermatology. 5th ed. Philadelphia, Pa: Mosby Elsevier; 2009:chap 3.

Atopic dermatitis. In: Habif TP, ed. Clinical Dermatology. 5th ed. Philadelphia, Pa: Mosby Elsevier; 2009:chap 5.

Greer FR, Sicherer SH, Burks, W and the Committee on Nutrition and Section on Allergy and Immunology. Effects of early nutritional interventions on the development of atopic disease in infants and children: The role of maternal dietary restriction, breastfeeding, timing of introduction of complementary foods, and hydrolyzed formulas. Pediatrics. 2008;121:183-191.

Lewis-Jones S, Mugglestone MA; Guideline Development Group. Management of atopic eczema in children aged up to 12 years: summary of NICE guidance. BMJ. 2007;335:1263-1264.

Ascroft DM, Chen LC, Garside R, Stein K, Williams HC. Topical pimecrolimus for eczema. Cochrane Database Syst Rev. 2007 Oct 17;(4):CD005500.

Bath-Hextall FJ, Delamere FM, Williams HC. Dietary exclusions for established atopic eczema. Cochrane Database Syst Rev. 2008 Jan 23;(1):CD005203.

Update Date: 11/21/2011

Updated by: Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.