ATOPIC DERMATITIS

Atopic dermatitis is a very common, often chronic (long-lasting) skin disease that affects a large percentage of the world’s population. It is also called eczema, dermatitis, or atopy. Most commonly, it may be thought of as a type of skin allergy or sensitivity. The atopic dermatitis triad includes asthma, allergies (hay fever), and eczema. There is a known hereditary component of the disease, and it is seen more in some families. The hallmarks of the disease include skin rashes and itching.

The word “dermatitis” means inflammation of the skin. “Atopic” refers to diseases that are hereditary, tend to run in families, and often occur together. In atopic dermatitis, the skin becomes extremely itchy and inflamed, causing redness, swelling, cracking, weeping, crusting, and scaling. Dry skin is a very common complaint and an underlying cause of some of the typical rash symptoms.

Although atopic dermatitis can occur in any age, most often it affects infants and young children. In some instances, it may persist into adulthood or actually first show up later in life. A large number of patients tend to have a long-term course with various ups and downs. In most cases, there are periods of time when the disease is worse, called exacerbations or flares, which are followed by periods when the skin improves or clears up entirely, called remissions. Many children with atopic dermatitis enter into a permanent remission of the disease when they get older, although their skin may remain somewhat dry and easily irritated.

Multiple factors can trigger or worsen atopic dermatitis, including dry skin, seasonal allergies, exposure to harsh soaps and detergents, new skin products or creams, and cold weather. Environmental factors can activate symptoms of atopic dermatitis at any time in the lives of individuals who have inherited the atopic disease trait.

Atopic dermatitis is typically a more specific set of three associated conditions occurring in the same person including eczema, allergies, and asthma. Not every component has to be present at the same time, but usually these patients are prone to all of these three related conditions.

The skin of a patient with atopic dermatitis reacts abnormally and easily to irritants, food, and environmental allergens and becomes red, flaky and very itchy. It also becomes vulnerable to surface infections caused by bacteria. The skin on the flexural surfaces of the joints (for example inner sides of elbows and knees) are the most commonly affected regions in people.

Atopic dermatitis often occurs together with other atopic diseases like hay fever,asthma and conjunctivitis. It is a familial and chronic disease and its symptoms can increase or disappear over time. Atopic dermatitis in older children and adults is often confused with psoriasis. Atopic dermatitis afflicts humans, particularly young children; it is also a well-characterized disease in domestic dogs.

Although there is no cure for atopic eczema, and its cause is not well understood, it can be treated very effectively in the short term through a combination of prevention (learning what triggers the allergic reactions) and drug therapy.

Allergy

Although it is an inherited disease, eczema is primarily aggravated by contact with or intake of allergens. It can also be influenced by other factors that affects the immune system such as stress or fatigue. Atopic eczema consists of chronic inflammation; it often occurs in people with a history of allergy disorders such as asthma or hay fever. There is no certain cause of atopic dermatitis. In dogs, atopic dermatitis can be caused by or aggravated by inhaled allergens, food allergens, and flea bites; however, in human, such relationships are not well established.

While not cause of atopic dermatitis, food allergy is often present in atopic children, and children with food allergy often present with skin dermatitis indistinguishable from atopic dermatitis. New-onset atopic dermatitis patients at a later age or severe atopic dermatitis often warrant referral to an allergist for food allergy testing. Many dermatologists and physicians test for food allergy in their office. The test is often done as a “pin prick” or “needle prick.” A drop of food extract is placed on the skin, and a small prick in the epidermis is performed. A “wheal” is produced with a positive test.

Common food allergen causing eczematous dermatitis include peanuts, tree nuts, shellfish, fish, milk, and egg. While food allergy induced eczematous dermatitis might present independent of atopic dermatitis, some children with atopic dermatitis also have concurrent food allergies.