Atopic Dermatitis Causes, Symptoms, Diagnosis, Treatment, Prevention

Atopic Dermatitis Causes, Symptoms, Diagnosis, Treatment, Prevention


What is atopic dermatitis?


Atopic dermatitis is a very common, often long-lasting skin disease that affects a large percentage of the world's population. It is a special type of allergic hypersensitivity that includes a triad of conditions that includes asthma, inhalant allergies (hay fever), and a chronic dermatitis (eczema). There is a known hereditary component of the disease, and it is more common in affected families. Criteria that enable your doctor to diagnose it include the typical appearance and distribution of the rash in a patient with a personal or family history of asthma and/or hay fever.

For some people, atopic dermatitis may be a long-lasting (chronic) skin problem that requires more than one treatment.

Atopic dermatitis is most common in babies and children. Some children with atopic dermatitis outgrow it or have milder cases as they get older. Also, a person may get atopic dermatitis as an adult.

Atopic dermatitis is sometimes called eczema or atopic eczema. But atopic dermatitis is only one of many types of eczema.

What is the difference between atopic dermatitis and eczema?


Eczema is a nonspecific term for many types of skin inflammation (dermatitis). There are different categories of eczema, like allergic, contact, irritant, and nummular eczema, which can be difficult to distinguish from atopic dermatitis. These types of eczema are listed and briefly described below. Atopy is a medical syndrome that includes three associated conditions that tend to occur in the same individual: atopic dermatitis, inhalant allergies, and asthma. All three components need not be present in the same individual simultaneously.

What causes atopic dermatitis?


The cause of atopic dermatitis is not clear, but it affects your skin's ability to hold moisture. Your skin becomes dry, itchy, and easily irritated.

People with atopic dermatitis have skin that is sensitive to irritants and dryness in the environment.

Most people who have atopic dermatitis have a personal or family history of allergies, such as hay fever (allergic rhinitis) and asthma. The skin inflammation that causes the atopic dermatitis rash is thought to be a type of allergic response.

Things that may make atopic dermatitis worse include:

  • Stress.
  • Certain foods, such as eggs, peanuts, milk, wheat, fish, or soy products. Food allergies trigger atopic dermatitis more commonly in babies and children than in adults.
  • Allergens, such as dust mites or animal dander.
  • Harsh soaps or detergents.
  • Weather changes, especially dry and cold.
  • Skin infection.

How common is atopic dermatitis?


Atopic dermatitis is very common worldwide and increasing in prevalence. It affects males and females equally and accounts for 10%-20% 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. Scientists estimate that 65% of patients develop symptoms in the first year of life, and 90% develop symptoms before the age of 5. Onset after age 30 is less common and often occurs after exposure of the skin to harsh conditions. People who live in urban areas and in climates with low humidity seem to be at an increased risk for developing atopic dermatitis.

About 10% of all infants and young children experience symptoms of the disease. Roughly 60% of these infants continue to have one or more symptoms of atopic dermatitis even after they reach adulthood. This means that more than 15 million people in the United States have symptoms of the disease.


What are atopic dermatitis symptoms and signs?


Signs and symptoms of atopic dermatitis (eczema) include:

  • Red to brownish-gray colored patches
  • Itching, which may be severe, especially at night
  • Small, raised bumps, which may leak fluid and crust over when scratched
  • Thickened, cracked or scaly skin
  • Raw, sensitive skin from scratching
Though the patches can occur anywhere, they most often appear on the hands and feet, in the front of the bend of the elbow, behind the knees, and on the ankles, wrists, face, neck and upper chest. Atopic dermatitis can also affect the skin around the eyes, including your eyelids. Scratching can cause redness and swelling around the eyes.

Atopic dermatitis most often begins in childhood before age 5 and may persist into adulthood. For some, it flares periodically and then subsides for a time, even up to several years. Itching may be severe, and scratching the rash can make it even itchier and cause more inflammation. Once the skin barrier is broken, the skin can become infected by bacteria, especially Staphylococcus aureus, which commonly live on the skin. Breaking this itch-scratch cycle can be challenging.

Factors that worsen atopic dermatitis


Most people with atopic dermatitis also have Staphylococcus aureus bacteria on their skin. The staph bacteria multiply rapidly when the skin barrier is broken and fluid is present on the skin, which in turn may worsen symptoms, particularly in young children.

Other factors that can worsen signs and symptoms of atopic dermatitis include:

  • Dry skin
  • Long, hot baths or showers
  • Stress
  • Sweating
  • Rapid changes in temperature
  • Low humidity
  • Solvents, cleaners, soaps or detergents
  • Wool or man-made fabrics or clothing
  • Dust or sand
  • Cigarette smoke
  • Living in cities where pollution is high
  • Certain foods, such as eggs, milk, fish, soy or wheat

Can atopic dermatitis affect the face?


Yes. Atopic dermatitis may affect the skin around the eyes, the eyelids, the eyebrows, and lashes. Scratching and rubbing the eye area can cause the skin to change in appearance. Some people with atopic dermatitis develop an extra fold of skin under their eyes, called an atopic pleat or Dennie-Morgan fold. Other people may have hyperpigmented eyelids, meaning that the skin on their eyelids darkens from the inflammation or hay fever (allergic shiners). Patchy eyebrows and eyelashes may also result from scratching or rubbing.

The face is very commonly affected in babies, who may drool excessively, and become irritated from skin contact with their flowing saliva.

The skin of a person with atopic dermatitis loses too much moisture from the epidermal layer. Some patients with atopic dermatitis lack a protein called fillagrin that is important in retaining moisture. This defective genetic trait allows the skin to become very dry, which reduces its protective abilities. In addition, the skin is very susceptible to recurring disorders, such as staphylococcal and streptococcal bacterial skin infections, warts, herpes simplex, and molluscum contagiosum (which is caused by a virus).

How is atopic dermatitis diagnosed?


A doctor can usually tell if you have atopic dermatitis by doing a physical exam and asking questions about your past health. Some of the questions might be: Do allergies run in your family? When did the itch first start? When did the rash first appear? Checking to see what the rash looks like and where it is located will help your doctor decide if you have atopic dermatitis.

Your doctor may advise allergy testing to find the things that trigger the rash. Allergy tests are done by an allergist (immunologist).

How is Atopic Dermatitis treated?


Treatments for atopic dermatitis (eczema) aim to reduce inflammation, relieve itching and prevent future flare-ups. Over-the-counter (nonprescription) anti-itch creams and other self-care measures may help control mild atopic dermatitis.

Although atopic dermatitis is related to allergies, eliminating allergens is rarely helpful in clearing the condition. Occasionally, items that trap dust — such as feather pillows, down comforters, mattresses, carpeting and drapes — can worsen the condition. Allergy shots usually aren't successful in treating atopic dermatitis.

Medications


Corticosteroid creams or ointments. Your doctor may recommend prescription corticosteroid creams or ointments to ease scaling and relieve itching. Some low-potency corticosteroid creams are available without a prescription, but you should always talk to your doctor before using any topical corticosteroid. Side effects of long-term or repeated use can include skin irritation or discoloration, thinning of the skin, infections, and stretch marks on the skin.

Antibiotics. You may need antibiotics if you have a bacterial skin infection or an open sore or fissure caused by scratching. Your doctor may recommend taking antibiotics for a short time to treat an infection or for longer periods of time to reduce bacteria on your skin and to prevent recurrent infections.

Oral antihistamines. If itching is severe, oral antihistamines may help. Diphenhydramine (Benadryl, others) can make you sleepy and may be helpful at bedtime. If your skin cracks open, your doctor may prescribe mildly astringent wet dressings to prevent infection.

Oral or injected corticosteroids. For more severe cases, your doctor may prescribe oral corticosteroids, such as prednisone, or an intramuscular injection of corticosteroids to reduce inflammation and to control symptoms. These medications are effective, but can't be used long term because of potential serious side effects, which include cataracts, loss of bone mineral (osteoporosis), muscle weakness, decreased resistance to infection, high blood pressure and thinning of the skin.

Immunomodulators. A class of medications called immunomodulators, such as tacrolimus (Protopic) and pimecrolimus (Elidel), affect the immune system and may help maintain normal skin texture and reduce flares of atopic dermatitis. This prescription-only medication is approved for children older than 2 and for adults. Due to possible concerns about the effect of these medications on the immune system when used for prolonged periods, the Food and Drug Administration recommends that Elidel and Protopic be used only when other treatments have failed or if someone can't tolerate other treatments.

Light therapy (phototherapy)


As the name suggests, this treatment uses natural or artificial light. The simplest and easiest form of phototherapy involves exposing your skin to controlled amounts of natural sunlight. Other forms of light therapy include the use of artificial ultraviolet A (UVA) or ultraviolet B (UVB) light including the more recently available narrow band ultraviolet B (NBUVB) either alone or with medications.

Though effective, long-term light therapy has many harmful effects, including premature skin aging and an increased risk of skin cancer. For these reasons, it's important to consult your doctor before using light exposure as treatment for atopic dermatitis. Your doctor can advise you of possible advantages and disadvantages of light exposure in your specific situation.

Infantile eczema


Treatment for infantile eczema includes identifying and avoiding skin irritations, avoiding extreme temperatures, and lubricating your baby’s skin with bath oils, lotions, creams or ointments.

See your baby's doctor if these measures don't improve the rash or if the rash looks infected. Your baby may need a prescription medication to control his or her symptoms or to treat the infection. Your doctor may recommend an oral antihistamine to help lessen the itch and to cause drowsiness, which may be helpful for nighttime itching and discomfort.

Prevention for Atopic Dermatitis


Bathe less frequently. Try going a day or two without a shower or bath. When you do bathe, limit yourself to 15 to 20 minutes, and use warm, rather than hot, water. Using a bath oil also may be helpful.

Use only certain soaps or synthetic detergents. Choose mild soaps that clean without excessively removing natural oils. Deodorant and antibacterial soaps may be more drying to your skin. Use soap only on your face, underarms, genital areas, hands and feet. Use clear water elsewhere.

Dry yourself carefully. Brush your skin rapidly with the palms of your hands, or gently pat your skin dry with a soft towel after bathing.

Moisturize your skin. Moisturizers provide a seal over your skin to keep water from escaping. Thicker moisturizers work best, such as over-the-counter brands Cetaphil, Vanicream and Eucerin. You may also want to use cosmetics that contain moisturizers. If your skin is extremely dry, you may want to apply an oil, such as baby oil, while your skin is still moist. Oil has more staying power than moisturizers do and prevents the evaporation of water from the surface of your skin.

Can you prevent your baby from getting atopic dermatitis?


If you or other family members have atopic dermatitis or other allergies, there is a chance that your baby could get it. If possible, breast-feed your baby for at least 6 months to boost the immune system and to help protect your baby.

What factors can aggravate atopic dermatitis?


Many factors or conditions can intensify the symptoms of atopic dermatitis, including dry skin, small changes in temperature, the low humidity of winter or cold weather, wool cloths, and other irritating skin conditions. These factors may further trigger the itch-scratch cycle, further stimulating the many times already overactive immune system in the skin. Repeated aggravation and activation of the itch-scratch cycle may cause further skin damage and barrier breakdown. These exacerbating elements can be broken down into two main categories: irritants and allergens. Emotional factors and some infections can also influence atopic dermatitis.

What are skin irritants in patients with atopic dermatitis?


Irritants are substances that directly affect the skin, and when used 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 families learn to identify the irritants that are most troublesome to them. For example, wool or synthetic fibers may affect some patients. Rough or poorly fitting clothing can rub the skin, trigger inflammation, and prompt the beginning of the itch-scratch cycle. 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 chlorine and solvents) or irritants (such as dust or sand) may also aggravate the condition. Cigarette smoke may irritate the eyelids. Because irritants vary from one person to another, each person has to determine for themselves what to avoid.