Atopic dermatitis

Atopic dermatitis

Fig.1.21.

Definition

Eczema is a general term used to describe a variety of conditions that cause an itchy, inflamed skin rash. Atopic dermatitis, a form of eczema, is a non-contagious disorder characterized by chronically inflamed skin and sometimes intolerable itching.

(Fig 1.21.)
A close-up view of atopic dermatitis in the crook of the elbow of a 12-year-old patient.



Description

Atopic dermatitis refers to a wide range of diseases that are often associated with stress and allergic disorders that involve the respiratory system, like asthma and hay fever. Although atopic dermatitis can appear at any age, it is most common in children and young adults. Symptoms usually abate before the age of 25 and do not affect the patient's general health.

About one in ten babies develop a form of atopic dermatitis called infantile eczema. Characterized by skin that oozes and becomes encrusted, infantile eczema most often occurs on the face and scalp. The condition usually improves before the child's second birthday, and medical attention can keep symptoms in check until that time.

When atopic dermatitis develops after infancy, inflammation, blistering, oozing, and crusting are less pronounced. The patient's sores become dry, turn from red to brownish-gray, and skinmay thicken and become scaly. In dark-skinned individuals, this condition can cause the complexion to lighten or darken. Itching associated with this condition is usually worst at night. It can be so intense that patients scratch until their sores bleed, sometimes causing scarring and infection.

Atopic dermatitis affects about 3% of the population of the United States, and about 80% of the people who have the condition have one or more relatives with the same condition or a similar one. Symptoms tend to be most severe in females. Atopic dermatitis can erupt on any part of the skin, and crusted, thickened patches on the fingers, palms, or the soles of the feet can last for years. In teenagers and young adults, atopic dermatitis often appears on one or more of the following areas:

  • elbow creases
  • backs of the knees
  • ankles
  • wrists
  • face
  • neck
  • upper chest
  • palms and between the fingers


Causes and symptoms

While allergic reactions often trigger atopic dermatitis, the condition is thought to be the result of an inherited over-active immune system or a genetic defect that causes the skin to lose abnormally large amounts of moisture. The condition can be aggravated by a cycle that develops in which the skin itches, the patient scratches, the condition worsens, the itching worsens, the patient scratches, etc. This cycle must be broken by relieving the itching to allow the skin time to heal. If the skin becomes broken, there is also a risk of developing skin infections which, if not recognized and treated promptly, can become more serious.

Symptoms of atopic dermatitis include the following:

  • an itchy rash and dry, thickened skin on areas of the body where moisture can be trapped
  • continual scratching
  • chronic fatigue, caused when itching disrupts sleep

An individual is more at-risk for developing the condition if there is a personal or family history of atopic dermatitis, hay fever, asthma, or other allergies. Exposure to any of the following can cause a flare-up:

  • hot or cold temperatures
  • wool and synthetic fabrics
  • detergents, fabric softeners, and chemicals
  • use of drugs that suppress immune-system activity

Certain foods, such as peanuts, cow's milk, eggs, and fish, can trigger symptoms of atopic dermatitis. A small percentage of patients with atopic dermatitis find that their symptoms worsen after having been exposed to dust, feather pillows, rough-textured fabrics, or other materials to which dust adheres.

Diagnosis

Diagnosis of atopic dermatitis is usually based on the patient's symptoms and personal and family health history. Skin tests do not generally provide reliable information about this condition.

Treatment

Atopic dermatitis cannot be cured, but the severity and duration of symptoms can be controlled. A dermatologist should be consulted when symptoms first appear, and is likely to recommend warm baths to loosen encrusted skin, followed by applications of petroleum jelly or vegetable shortening to prevent the skin's natural moisture from escaping.

Externally applied (topical) steroids or preparations containing coal tar can relieve minor itching, but coal tar has an unpleasant odor, stains clothes, and may increase skin-cancer risk. Excessive use of steroid creams in young children can alter growth. Pregnant women should not use products that contain coal tar. Topical steroids can cause itching, burning, acne, permanent stretch marks, and thinning and spotting of the skin. Applying topical steroids to the area around the eyes can cause glaucoma.

Oral antihistamines, such as diphenhydramine (Benadryl), can relieve symptoms of allergy-related atopic dermatitis. More concentrated topical steroids are recommended for persistent symptoms. A mild tranquilizer may be prescribed to reduce stress and help the patient sleep, and antibiotics are used to treat secondary infections.

Cortisone ointments should be used sparingly, and strong preparations should never be applied to the face, groin, armpits, or rectal area. Regular medical monitoring is recommended for patients who use cortisone salves or lotions to control wide-spread symptoms. Oral cortisone may be prescribed if the patient does not respond to other treatments, but patients who take the medication for more than two weeks have a greater-than-average risk of developing severe symptoms when the treatment is discontinued.

Allergy shots rarely improve atopic dermatitis and sometimes aggravate the symptoms. Since food allergies may trigger atopic dermatitis, the doctor may suggest eliminating certain foods from the diet if other treatments prove ineffective.

If symptoms are extremely severe, ultraviolet light therapy may be prescribed, and a wet body wrap recommended to help the skin retain moisture. This technique, used most often with children, involves sleeping in a warm room while wearing wet pajamas under dry clothing, rain gear, or a nylon sweatsuit. The patient's face may be covered with wet gauze covered by elastic bandages, and his or her hands encased in wet socks covered by dry ones.

A physician should be notified if the condition is widespread or resists treatment, or the skin oozes, becomes encrusted, or smells, as this may indicate an infection.

Alternative treatment

Alternative therapies can sometimes bring relief or resolution of atopic dermatitis when conventional therapies are not helping. If the condition becomes increasingly widespread or infected, a physician should be consulted.

Helpful alternative treatments for atopic dermatitis may include:

  • Taking regular brisk walks, followed by bathing in warm water sprinkled with essential oil of lavender (Lavandula officinalis); lavender oil acts as a nerve relaxant for the whole body including the skin
  • Supplementing the diet daily with zinc, fish oils, vitamin A, vitamin E, and evening primrose oil (Oenothera biennis)-all good sources of nutrients for the skin
  • Reducing or eliminating red meat from the diet
  • Eliminating or rotating potentially allergic foods such as cow's milk, peanuts, wheat, eggs, and soy
  • Implementing stress reduction techniques in daily life.

Herbal therapies also can be helpful in treating atopic dermatitis. Western herbal remedies used in the treatment of this condition include burdock (Arctium lappa) and Ruta (Ruta graveolens). Long-term herbal therapy requires monitoring and should be guided by an experienced practitioner.

Other alternative techniques that may be useful in the treatment of atopic dermatitis include:

  • Acupressure (acupuncture without needles) to relieve tension that may trigger a flare
  • Aromatherapy, using essential oils like lavender, thyme (Thymus vulgaris), jasmine (Jasminum officinale) and chamomile (Matricaria recutita) in hot water, to add a soothing fragrance to the air
  • Shiatsu massage and reflexology, performed by licensed practitioners, to alleviate symptoms by restoring the body's natural balance
  • Homeopathy, which may temporarily worsen symptoms before relieving them, should be supervised by a trained alternative healthcare professional
  • Hydrotherapy, which uses water, ice, liquid, and steam, to stimulate the immune system
  • Juice therapy to purify the liver and relieve bowel congestion
  • Yoga to induce a sense of serenity.

Prognosis

Atopic dermatitis is unpredictable. Although symptoms occur less often with age and sometimes disappear altogether, they can recur without warning. Atopic dermatitis lowers resistance to infection and increases the risk of developing cataracts. Sixty percent of patients with atopic dermatitis will experience flares and remissions throughout their lives.

Prevention

Research has shown that babies weaned from breast milk before they are four months old are almost three times more likely than other babies to develop recurrent eczema. Feeding eggs or fish to a baby less than one year old can activate symptoms, and babies should be shielded from such irritants as mites, molds, pet hair, and smoke.

Possible ways to prevent flare-ups include the following:

  • eliminate activities that cause sweating
  • lubricate the skin frequently
  • avoid wool, perfumes, fabric softeners, soaps that dry the skin, and other irritants
  • avoid sudden temperature changes

A doctor should be notified whenever any of the following occurs:

  • fever or relentless itching develop during a flare
  • an unexplained rash develops in someone who has a personal or family history of eczema or asthma
  • inflammation does not decrease after seven days of treatment with an over-the-counter preparation containing coal tar or steroids
  • a yellow, tan, or brown crust or pus-filled blisters appear on top of an existing rash
  • a person with active atopic dermatitis comes into contact with someone who has cold sores, genital herpes, or another viral skin disease