Defining Atopic Dermatitis

Atopic dermatitis is a chronic (long-lasting) disease that affects the skin. It is not contagious; it cannot be passed from one person to another. The word "dermatitis" means inflammation of the skin. "Atopic" refers to a group of diseases where there is often an inherited tendency to develop other allergic conditions, such as asthma and hay fever. In atopic dermatitis, the skin becomes extremely itchy. Scratching leads to redness, swelling, cracking, "weeping" clear fluid, and finally, crusting and scaling. In most cases, there are periods of time when the disease is worse (called exacerbations or flares) followed by periods when the skin improves or clears up entirely (called remissions). As some children with atopic dermatitis grow older, their skin disease improves or disappears altogether, although their skin often remains dry and easily irritated. In others, atopic dermatitis continues to be a significant problem in adulthood.

Atopic dermatitis is often referred to as "eczema," which is a general term for the several types of inflammation of the skin. Atopic dermatitis is the most common of the many types of eczema. Several have very similar symptoms. Types of eczema are described in the box on page 5.

Incidence and Prevalence of Atopic Dermatitis

Atopic dermatitis is very common. It affects males and females and accounts for 10 to 20 percent of all visits to dermatologists (doctors who specialize in the care and treatment of skin diseases). Although atopic dermatitis may occur at any age, it most often begins in infancy and childhood. Scientists estimate that 65 percent of patients develop symptoms in the first year of life, and 90 percent develop symptoms before the age of 5. Onset after age 30 is less common and is often due to exposure of the skin to harsh or wet conditions. Atopic dermatitis is a common cause of workplace disability. People who live in cities and in dry climates appear more likely to develop this condition.

Although it is difficult to identify exactly how many people are affected by atopic dermatitis, an estimated 20 percent of infants and young children experience symptoms of the disease. Roughly 60 percent of these infants continue to have one or more symptoms of atopic dermatitis in adulthood. This means that more than 15 million people in the United States have symptoms of the disease.

Types of Eczema (Dermatitis)

·         Allergic contact eczema (dermatitis): a red, itchy, weepy reaction where the skin has come into contact with a substance that the immune system recognizes as foreign, such as poison ivy or certain preservatives in creams and lotions

·         Atopic dermatitis: a chronic skin disease characterized by itchy, inflamed skin

·         Contact eczema: a localized reaction that includes redness, itching, and burning where the skin has come into contact with an allergen (an allergy-causing substance) or with an irritant such as an acid, a cleaning agent, or other chemical

·         Dyshidrotic eczema: irritation of the skin on the palms of hands and soles of the feet characterized by clear, deep blisters that itch and burn

·         Neurodermatitis: scaly patches of the skin on the head, lower legs, wrists, or forearms caused by a localized itch (such as an insect bite) that become intensely irritated when scratched

·         Nummular eczema: coin-shaped patches of irritated skin-most common on the arms, back, buttocks, and lower legs-that may be crusted, scaling, and extremely itchy

·         Seborrheic eczema: yellowish, oily, scaly patches of skin on the scalp, face, and occasionally other parts of the body

·         Stasis dermatitis: a skin irritation on the lower legs, generally related to circulatory problems

Causes of Atopic Dermatitis

The cause of atopic dermatitis is not known, but the disease seems to result from a combination of genetic (hereditary) and environmental factors.

Children are more likely to develop this disorder if one or both parents have had it or have had allergic conditions like asthma or hay fever. While some people outgrow skin symptoms, approximately three-fourths of children with atopic dermatitis go on to develop hay fever or asthma. Environmental factors can bring on symptoms of atopic dermatitis at any time in individuals who have inherited the atopic disease trait.

Atopic dermatitis is also associated with malfunction of the body's immune system: the system that recognizes and helps fight bacteria and viruses that invade the body. Scientists have found that people with atopic dermatitis have a low level of a cytokine (a protein) that is essential to the healthy function of the body's immune system and a high level of other cytokines that lead to allergic reactions. The immune system can become misguided and create inflammation in the skin even in the absence of a major infection. This can be viewed as a form of autoimmunity, where a body reacts against its own tissues.

In the past, doctors thought that atopic dermatitis was caused by an emotional disorder. We now know that emotional factors, such as stress, can make the condition worse, but they do not cause the disease.

Symptoms of Atopic Dermatitis

Symptoms (signs) vary from person to person. The most common symptoms are dry, itchy skin and rashes on the face, inside the elbows and behind the knees, and on the hands and feet. Itching is the most important symptom of atopic dermatitis. Scratching and rubbing in response to itching irritates the skin, increases inflammation, and actually increases itchiness. Itching is a particular problem during sleep when conscious control of scratching is lost.

The appearance of the skin that is affected by atopic dermatitis depends on the amount of scratching and the presence of secondary skin infections. The skin may be red and scaly, be thick and leathery, contain small raised bumps, or leak fluid and become crusty and infected. The box on page 8 lists common skin features of the disease. These features can also be found in people who do not have atopic dermatitis or who have other types of skin disorders.

Atopic dermatitis may also affect the skin around the eyes, the eyelids, and the eyebrows and lashes. Scratching and rubbing the eye area can cause the skin to redden and swell. Some people with atopic dermatitis develop an extra fold of skin under their eyes. Patchy loss of eyebrows and eyelashes may also result from scratching or rubbing.

Researchers have noted differences in the skin of people with atopic dermatitis that may contribute to the symptoms of the disease. The outer layer of skin, called the epidermis, is divided into two parts: an inner part containing moist, living cells, and an outer part, known as the horny layer or stratum corneum, containing dry, flattened, dead cells. Under normal conditions the stratum corneum acts as a barrier, keeping the rest of the skin from drying out and protecting other layers of skin from damage caused by irritants and infections. When this barrier is damaged, irritants act more intensely on the skin.

The skin of a person with atopic dermatitis loses moisture from the epidermal layer, allowing the skin to become very dry and reducing its protective abilities. Thus, when combined with the abnormal skin immune system, the person's skin is more likely to become infected by bacteria (for example, Staphylo-coccus and Streptococcus) or viruses, such as those that cause warts and cold sores.

Diagnosing Atopic Dermatitis

Each person experiences a unique combination of symptoms, which may vary in severity over time. The doctor will base a diagnosis on the symptoms the patient experiences and may need to see the patient several times to make an accurate diagnosis and to rule out other diseases and conditions that might cause skin irritation. In some cases, the family doctor or pediatrician may refer the patient to a dermatologist (doctor specializing in skin disorders) or allergist (allergy specialist) for further evaluation.

A medical history may help the doctor better understand the nature of a patient's symptoms, when they occur, and their possible causes. The doctor may ask about family history of allergic disease; whether the patient also has diseases such as hay fever or asthma; and about exposure to irritants, sleep disturbances, any foods that seem to be related to skin flares, previous treatments for skin-related symptoms, and use of steroids or other medications. A preliminary diagnosis of atopic dermatitis can be made if the patient has three or more features from each of two categories: major features and minor features. Some of these features are listed in the box on page 14.

Currently, there is no single test to diagnose atopic dermatitis. However, there are some tests that can give the doctor an indication of allergic sensitivity.

Pricking the skin with a needle that contains a small amount of a suspected allergen may be helpful in identifying factors that trigger flares of atopic dermatitis. Negative results on skin tests may help rule out the possibility that certain substances cause skin inflammation. Positive skin prick test results are difficult to interpret in people with atopic dermatitis because the skin is very sensitive to many substances, and there can be many positive test sites that are not meaningful to a person's disease at the time. Positive results simply indicate that the individual has IgE (allergic) antibodies to the substance tested. IgE (immunoglobulin E) controls the immune system's allergic response and is often high in atopic dermatitis.

Recently, it was shown that if the quantity of IgE antibodies to a food in the blood is above a certain level, it is diagnostic of a food allergy. If the level of IgE to a specific food does not exceed the level needed for diagnosis but a food allergy is suspected, a person might be asked to record everything eaten and note any reactions. Physician-supervised food challenges (that is, the introduction of a food) following a period of food elimination may be necessary to determine if symptomatic food allergy is present. Identifying the food allergen may be difficult when a person is also being exposed to other possible allergens at the same time or symptoms may be triggered by other factors, such as infection, heat, and humidity.

Major and Minor Features of Atopic Dermatitis

Major Features

·         Intense itching

·         Characteristic rash in locations typical of the disease

·         Chronic or repeatedly occurring symptoms

·         Personal or family history of atopic disorders (eczema, hay fever, asthma)

Some Minor Features

·         Early age of onset

·         Dry skin that may also have patchy scales or rough bumps

·         High levels of immunoglobulin E (IgE), an antibody, in the   blood

·         Numerous skin creases on the palms

·         Hand or foot involvement

·         Inflammation around the lips

·         Nipple eczema

·         Susceptibility to skin infection

·         Positive allergy skin tests

Factors That Make Atopic Dermatitis Worse

Many factors or conditions can make symptoms of atopic dermatitis worse, further triggering the already overactive immune system, aggravating the itch-scratch cycle, and increasing damage to the skin. These factors can be broken down into two main categories: irritants and allergens. Emotional factors and some infections and illnesses can also influence atopic dermatitis.

Irritants are substances that directly affect the skin and, when present in high enough concentrations with long enough contact, cause the skin to become red and itchy or to burn. Specific irritants affect people with atopic dermatitis to different degrees. Over time, many patients and their family members learn to identify the irritants causing the most trouble. For example, frequent wetting and drying of the skin may affect the skin barrier function. Also, wool or synthetic fibers and rough or poorly fitting clothing can rub the skin, trigger inflammation, and cause the itch-scratch cycle to begin. Soaps and detergents may have a drying effect and worsen itching, and some perfumes and cosmetics may irritate the skin. Exposure to certain substances, such as solvents, dust, or sand, may also make the condition worse. Cigarette smoke may irritate the eyelids. Because the effects of irritants vary from one person to another, each person can best determine what substances or circumstances cause the disease to flare.

Allergens are substances from foods, plants, animals, or the air that inflame the skin because the immune system overreacts to the substance. Inflammation occurs even when the person is exposed to small amounts of the substance for a limited time. Although it is known that allergens in the air, such as dust mites, pollens, molds, and dander from animal hair or skin, may worsen the symptoms of atopic dermatitis in some people, scientists aren't certain whether inhaling these allergens or their actual penetration of the skin causes the problems. When people with atopic dermatitis come into contact with an irritant or allergen they are sensitive to, inflammation-producing cells become active. These cells release chemicals that cause itching and redness. As the person responds by scratching and rubbing the skin, further damage occurs.

A number of studies have shown that foods may trigger or worsen atopic dermatitis in some people, particularly infants and children. In general, the worse the atopic dermatitis and the younger the child, the more likely food allergy is present. An allergic reaction to food can cause skin inflammation (generally an itchy red rash), gastrointestinal symptoms (abdominal pain, vomiting, diarrhea), and/or upper respiratory tract symptoms (congestion, sneezing, and wheezing). The most common allergenic (allergy-causing) foods are eggs, milk, peanuts, wheat, soy, and fish. A recent analysis of a large number of studies on allergies and breastfeeding indicated that breastfeeding an infant for at least 4 months may protect the child from developing allergies. However, some studies suggest that mothers with a family history of atopic diseases should avoid eating common allergenic foods during late pregnancy and breastfeeding.

In addition to irritants and allergens, emotional factors, skin infections, and temperature and climate play a role in atopic dermatitis. Although the disease itself is not caused by emotional factors, it can be made worse by stress, anger, and frustration. Interpersonal problems or major life changes, such as divorce, job changes, or the death of a loved one, can also make the disease worse.

Bathing without proper moisturizing afterward is a common factor that triggers a flare of atopic dermatitis. The low humidity of winter or the dry year-round climate of some geographic areas can make the disease worse, as can overheated indoor areas and long or hot baths and showers. Alternately sweating and chilling can trigger a flare in some people. Bacterial infections can also trigger or increase the severity of atopic dermatitis. If a patient experiences a sudden flare of illness, the doctor may check for infection.

Treatment of Atopic Dermatitis

Treatment is more effective when a partnership develops that includes the patient, family members, and doctor. The doctor will suggest a treatment plan based on the patient's age, symptoms, and general health. The patient or family member providing care plays a large role in the success of the treatment plan by carefully following the doctor's instructions and paying attention to what is or is not helpful. Most patients will notice improvement with proper skin care and lifestyle changes.

The doctor has two main goals in treating atopic dermatitis: healing the skin and preventing flares. These may be assisted by developing skin care routines and avoiding substances that lead to skin irritation and trigger the immune system and the itch-scratch cycle. It is important for the patient and family members to note any changes in the skin's condition in response to treatment, and to be persistent in identifying the treatment that seems to work best.

Medications: New medications known as immuno-modulators have been developed that help control inflammation and reduce immune system reactions when applied to the skin. Examples of these medications are tacrolimus ointment (Protopic*) and pimecrolimus cream (Elidel). They can be used in patients older than 2 years of age and have few side effects (burning or itching the first few days of application). They not only reduce flares, but also maintain skin texture and reduce the need for long-term use of corticosteroids.

*Brand names included in this booklet are provided as examples only, and their inclusion does not mean that these products are endorsed by the National Institutes of Health or any other Government agency. Also, if a particular brand name is not mentioned, this does not mean or imply that the product is unsatisfactory.

Corticosteroid creams and ointments have been used for many years to treat atopic dermatitis and other autoimmune diseases affecting the skin. Sometimes over-the-counter preparations are used, but in many cases the doctor will prescribe a stronger corticosteroid cream or ointment. When prescribing a medication, the doctor will take into account the patient's age, location of the skin to be treated, severity of the symptoms, and type of preparation (cream or ointment) that will be most effective. Sometimes the base used in certain brands of corticosteroid creams and ointments irritates the skin of a particular patient. Side effects of repeated or long-term use of topical corticosteroids can include thinning of the skin, infections, growth suppression (in children), and stretch marks on the skin.

When topical corticosteroids are not effective, the doctor may prescribe a systemic corticosteroid, which is taken by mouth or injected instead of being applied directly to the skin. An example of a commonly prescribed corticosteroid is prednisone. Typically, these medications are used only in resistant cases and only given for short periods of time. The side effects of systemic corticosteroids can include skin damage, thinned or weakened bones, high blood pressure, high blood sugar, infections, and cataracts. It can be dangerous to suddenly stop taking corticosteroids, so it is very important that the doctor and patient work together in changing the corticosteroid dose.

Antibiotics to treat skin infections may be applied directly to the skin in an ointment, but are usually more effective when taken by mouth. If viral or fungal infections are present, the doctor may also prescribe specific medications to treat those infections.

Certain antihistamines that cause drowsiness can reduce nighttime scratching and allow more restful sleep when taken at bedtime. This effect can be particularly helpful for patients whose nighttime scratching makes the disease worse.

In adults, drugs that suppress the immune system, such as cyclosporine, methotrexate, or azathioprine, may be prescribed to treat severe cases of atopic dermatitis that have failed to respond to other forms of therapy. These drugs block the production of some immune cells and curb the action of others. The side effects of drugs like cyclosporine can include high blood pressure, nausea, vomiting, kidney problems, headaches, tingling or numbness, and a possible increased risk of cancer and infections. There is also a risk of relapse after the drug is stopped. Because of their toxic side effects, systemic corticosteroids and immunosuppressive drugs are used only in severe cases and then for as short a period of time as possible. Patients requiring systemic corticosteroids should be referred to dermatologists or allergists specializing in the care of atopic dermatitis to help identify trigger factors and alternative therapies.

In rare cases, when home-based treatments have been unsuccessful, a patient may need a few days in the hospital for intense treatment.

Phototherapy: Use of ultraviolet A or B light waves, alone or combined, can be an effective treatment for mild to moderate dermatitis in older children (over 12 years old) and adults. A combination of ultraviolet light therapy and a drug called psoralen can also be used in cases that are resistant to ultraviolet light alone. Possible long-term side effects of this treatment include premature skin aging and skin cancer. If the doctor thinks that phototherapy may be useful to treat the symptoms of atopic dermatitis, he or she will use the minimum exposure necessary and monitor the skin carefully

Skin Care: Healing the skin and keeping it healthy are important to prevent further damage and enhance quality of life. Developing and sticking with a daily skin care routine is critical to preventing flares.

A lukewarm bath helps to cleanse and moisturize the skin without drying it excessively. Because soaps can be drying to the skin, the doctor may recommend use of a mild bar soap or nonsoap cleanser. Bath oils are not usually helpful.

After bathing, a person should air-dry the skin, or pat it dry gently (avoiding rubbing or brisk drying), and then apply a lubricant to seal in the water that has been absorbed into the skin during bathing. In addition to restoring the skin's moisture, lubrication increases the rate of healing and establishes a barrier against further drying and irritation. Lotions that have a high water or alcohol content evaporate more quickly, and alcohol may cause stinging. Therefore, they generally are not the best choice. Creams and ointments work better at healing the skin.

Another key to protecting and restoring the skin is taking steps to avoid repeated skin infections. Signs of skin infection include tiny pustules (pus-filled bumps), oozing cracks or sores, or crusty yellow blisters. If symptoms of a skin infection develop, the doctor should be consulted and treatment should begin as soon as possible.

Protection from Allergen Exposure: The doctor may suggest reducing exposure to a suspected allergen. For example, the presence of the house dust mite can be limited by encasing mattresses and pillows in special dust-proof covers, frequently washing bedding in hot water, and removing carpeting. However, there is no way to completely rid the environment of airborne allergens.

Changing the diet may not always relieve symptoms of atopic dermatitis. A change may be helpful, however, when the medical history, laboratory studies, and specific symptoms strongly suggest a food allergy. It is up to the patient and his or her family and physician to decide whether the dietary restrictions are appropriate. Unless properly monitored by a physician or dietitian, diets with many restrictions can contribute to serious nutritional problems, especially in children.

References:

National Institutes of Health (NIH)

Nutritional and Herbal Therapy for Dermatitis

• Avoid allergenic foods such as dairy products, soy, tomatoes, peanuts, wheat, shell fish, eggs, corn, and citrus.
• Consume more fresh vegetables, whole grains, and essential fatty acids (cold-water fish, nuts, and seeds).
• Vitamin E (100 to 400 IU per day), beta-carotene (25,000 to 100,000 IU/day) and zinc (10 to 30 mg per day) to bolster your immune system and help heal your skin.
• Flaxseed (3,000 mg twice a day), borage (1,500 mg twice a day) or evening primrose oil (1,500 mg twice a day) to reduce inflammation and swelling. Children can take cod liver oil (¹/2 to 1 tsp. per day), or any of the above oils, 500 mg, twice a day.
• From the Tao of Nutrition, you can try applying honey to the affected area, or mashed daikon radish, or fresh potato (changing every 4 hours, for 3 days). Also, there are a variety of teas that you can drink that may help: a mung bean/pearl barley combination, a dandelion/cornsilk combination, or a tea made from lily bulbs/Chinese black dates/mulberries.
• Healthy skin begins with healthy amounts of Blood and Qi - Traditions of Tao's Blood Builder nourishes Blood and Qi.
• The following Chinese herbal patent formulas can help treat eczema and allergic dermatitis : Kai Yeung Pill, Lian Qiao Bai Du Pian, and Chuan Shan Jia Qu Shi Qing Du Wan.
• Apply Pi Kang Shuang on the affected areas. This is a Chinese herbal topical cream that helps relieve itchiness and inflammation.
• Dr. Li's Protective Moisturizer can help relieve skin dryness and flakiness.

References:

Tao of Nutrition, by Maoshing Ni, Ph.D., C.A., and Cathy McNease, B.S., M.H.