Causes And Prevention Of Atopic Dermatitis

Atopic dermatitis is a chronic (long-lasting) disease that affects the skin. The word dermatitis means inflammation of the skin. Atopic refers to a group of diseases that are hereditary (that is, run in families) and often occur together, including asthma, allergies such as hay fever, and atopic dermatitis. In atopic dermatitis, the skin becomes extremely itchy and inflamed, causing redness, swelling, cracking, weeping, crusting, and scaling. Atopic dermatitis most often affects infants and young children, but it can continue into adulthood or first show up later in life. 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. Many children with atopic dermatitis will experience a permanent remission of the disease when they get older, although their skin often remains dry and easily irritated. Environmental factors can bring on symptoms of atopic dermatitis at any time in the lives of individuals who have inherited the atopic disease trait.

Atopic dermatitis is often referred to as eczema, which is a general term for the many types of dermatitis. Atopic dermatitis is the most common of the many types of eczema. Several have very similar symptoms.

Atopic dermatitis is very common. It affects males and females equally and accounts for 10 to 20 percent of all referrals to dermatologists (doctors who specialize in the care and treatment of skin diseases). Atopic dermatitis occurs most often in infants and children and its onset decreases substantially with age.

The cause of atopic dermatitis is not known, but the disease seems to result from a combination of genetic (hereditary) and environmental factors. Evidence suggests the disease is associated with other so-called atopic disorders such as hay fever and asthma, which many people with atopic dermatitis also have. In addition, many children who outgrow the symptoms of atopic dermatitis go on to develop hay fever or asthma. Although one disorder does not cause another, they may be related, thereby giving researchers clues to understanding atopic dermatitis.

Types of Eczema (Dermatitis)

  • 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.
  • 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.
  • Seborrheic eczema: yellowish, oily, scaly patches of skin on the scalp, face, and occasionally other parts of the body.
  • 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.
  • Neurodermatitis: scaly patches of skin on the head, lower legs, wrists, or forearms caused by a localized itch (such as an insect bite) that becomes intensely irritated when scratched.
  • Stasis dermatitis: a skin irritation on the lower legs, generally related to circulatory problems.
  • 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.

Symptoms vary from person to person. The most common symptoms are dry, itchy skin; cracks behind the ears; and rashes on the cheeks, arms, and legs. The itchy feeling is an important factor in atopic dermatitis, because scratching and rubbing in response to itching worsen the skin inflammation characteristic of this disease. People with atopic dermatitis seem to be more sensitive to itching and feel the need to scratch longer in response. They develop what is referred to as the itch-scratch cycle: The extreme itchiness of the skin causes the person to scratch, which in turn worsens the itch, and so on. Itching is particularly a problem during sleep, when conscious control of scratching decreases and the absence of other outside stimuli makes the itchiness more noticeable.

The skin of a person with atopic dermatitis loses too much moisture from the epidermal layer, allowing the skin to become very dry and reducing its protective abilities. In addition, the patient's skin is very susceptible to recurring infections, such as staphylococcal and streptococcal bacterial skin infections and warts, herpes simplex, and molluscum contagiosum (skin disorders caused by a viruses).

Allergens are substances from foods, plants, or animals 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. Some examples of allergens are pollen and dog or cat dander (tiny particles from the animal's skin or hair). When people with atopic dermatitis come into contact with an irritant or allergen they are sensitive to, inflammation-producing cells come into the skin from elsewhere in the body. These cells release chemicals that cause itching and redness. As the person scratches and rubs the skin in response, further damage occurs.

Some doctors and scientists believe that certain foods act as allergens and may trigger atopic dermatitis or cause it to become worse. Other researchers think that food allergens play a role in only a limited number of cases of atopic dermatitis, primarily in infants and children. An allergic reaction to food can cause skin inflammation (generally hives), gastrointestinal symptoms (vomiting, diarrhea), upper respiratory tract symptoms (congestion, sneezing), and wheezing. The most common allergenic (allergy-causing) foods are eggs, peanuts, milk, fish, soy products, and wheat.

Corticosteroid creams and ointments are the most frequently used treatment. Sometimes over-the-counter preparations are used, but in many cases the doctor will prescribe a stronger corticosteroid cream or ointment. 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) when prescribing a medication. Sometimes the base used in certain brands of corticosteroid creams and ointments is irritating for a particular patient.

Some treatments reduce specific symptoms of the disease. Antibiotics to treat skin infections may be applied directly to the skin in an ointment, but are usually more effective when taken by mouth. Certain antihistamines that cause drowsiness can reduce nighttime scratching and allow more restful sleep when taken at bedtime.

There are no specific therapeutic modalities for complete control of atopic dermatitis. Management must be individualized to improve morbidity (itching and scratching) with the goal to allow most patients to function in a normal productive manner.

Several experimental treatments are being evaluated that attempt to replace substances that are deficient in people with atopic dermatitis. Evening primrose oil is a substance rich in gamma-linolenic acid, one of the fatty acids that is decreased in the skin of people with atopic dermatitis. Studies to date using evening primrose oil have yielded contradictory results. Clinical trials with another substance, a dietary fatty acid supplement called eicosapentenoic acid, have resulted in only slight improvement. There is also a great deal of interest in the use of Chinese herbs and herbal teas to treat the disease. Studies to date do show some benefit, but not without concerns about toxicity and the risks of suppression of the immune system.

Treatment may include the following:

Oral ketotifen (a mast cell stabilizer)
Caffeine administered topically, 10% to 30% in petrolatum or water-in-oil base
Vitamins :- A, B Complex (high Potency), B6, Biotin, C
Minerals :- Chelated Multi Minerals, Zinc Magnesium
Food Supplements :-Nutritional Yeast, Lecithin, Linseed Oil, Rutin & Bioflavonoids, Linoleic acid, g -Linoleic acids
Herbs :- Evening Primrose Oil, Dandelion, echinacea">Echinacea, Milk Thistle

The herbs/nutrients mentioned above reflect the major nutritional supplements that may help the condition. Please do remember however that nutritional supplementation is an adjunct to medical treatment and in no way replaces medical treatment.

- Handout on Health: Atopic Dermatitis - National Institute of Arthritis and Musculoskeletal and Skin Diseases - National Institutes of Health
NIAMS gratefully acknowledges the assistance of Alan Moshell, M.D., NIAMS, NIH; Jon Hanifin, M.D., Oregon Health Sciences University, Portland, Oregon; Amy Paller, M.D., Children's Hospital of Chicago, Chicago, Illinois; Donald Leung, M.D., Ph.D., National Jewish Medical Center, Denver, Colorado; and Kevin Cooper, M.D., Case Western Reserve University, University Hospitals of Cleveland, Cleveland, Ohio, in the preparation and review of this publication.

Additional Resources
National Eczema Association
1221 SW Yamhill, Suite 303
Portland, OR 97205
(503) 228-4430
This is a national, patient-oriented association devoted to eczema. It publishes a newsletter and an eight-page brochure on atopic dermatitis, provides educational materials, offers resource services for people with atopic dermatitis, and provides referrals to atopic dermatitis research centers.

Discuss It!