SKINIPEDIA - Skin Encyclopedia: Eczema Atopic Dermatitis
Eczema Atopic Dermatitis a knol / article by Brian Cho, MD, Ph.D.; originally appeared HERE.
Introduction
Eczema is a common skin disorder that affects about one of every ten children. The condition can occur at any age but is most common in infants and young adults. Eczema occurs in all races. Ninety percent of patients who will develop eczema will have symptoms by five years of age; ninety-five percent by fifteen years of age. There is no single lab test or biopsy that will diagnose eczema. The diagnosis is based upon the appearance and symptoms of the skin rash, as well as whether related medical conditions, such as hay fever or asthma, are present in the patient or the patient’s family members.
Skin affected by eczema is dry and itchy and can become red, thickened, and scaly as the condition worsens. The skin rash can be limited to a just a few areas or be more widespread. In infants, the face and scalp are the most common sites. In children and young adults the bends of the wrists, elbows, neck, knees and ankles (flexural regions) are most common. Itching is often the most bothersome symptom. Some patients may scratch the skin until it bleeds or crusts; when this occurs the skin can become infected. The skin rashes frequently come and go. In seventy five percent of affected children, the condition greatly improves with adolescence, but twenty-five percent of patients may be affected throughout life, although not as severely as in early childhood.
In many children, the risk for developing eczema is inherited from one or both parents. Scientist do not believe one particular gene is involved; more likely it is a combination of genes plus the right environmental conditions that cause eczema to develop. Environmental triggers of eczema include allergies, infection, emotional stress, and conditions that dry the skin such as cold weather or drying soaps. Eczema tends to improve during warm, humid months and worsen during the fall and winter.
For more information on eczema:
Signs and Symptoms:
The most common symptom of eczema is itch. The affected areas of skin are often dry, red, scaly, circular patches, or red bumps. Sometimes the skin will ooze and crust. Without proper treatment, the skin thickens, to protect itself from further damage caused by scratching. Dermatologists call this thickening of the skin “lichenification.”
Eczema can occur on just about any surface of the body. The common sites where eczema occurs tends to change with age:
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Infants (birth to 3yrs): Common sites include both sides of face (particularly cheeks and forehead), the scalp, and folds of the neck. The folds of the arms and legs may also be involved.
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Childhood (4 to 10yrs): Common sites include the wrist, arms, ear creases, neck folds, and ankles.
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Adolescence and adulthood: Although arms and legs are affected, hand and foot eczema may become more common.
As noted, eczema can occur anywhere on the skin at any age, including around the eyes and on the eyelids. Up to one-third of eczema patients have a personal history of hay fever. Two-thirds have a family history (mother, father, brother, sister) of hay feveror asthma.
Other Findings or Conditions Commonly Found in Eczema Patients
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Keratosis Pilaris: 1-2mm scaly red bumps centered around hair follicles, usually on upper arms, inner thighs, and cheeks.
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Infraorbital folds: (also known as Dennie Morgan line) A symmetric, prominent fold (single or double) beneath the lower eyelid present at birth or developing shortly after birth.
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Hyperlinear palms: Increased number of creases on the palm of the hand.
Subtypes of Eczema
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Nummular: Discrete coin-shaped, red patches, most commonly found on legs. Affected skin may have small, fluid filled blisters.
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Hand/Dyshidrotic: Eczema with intensely itchy, deep-seated water blisters that resemble tapioca pudding; occurs on the hands, soles of feet, or sides of fingers. Instead of itch, patients may sometime complain of burning sensation.
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Xerotic/Asteatotic (Winter’s itch): Dry, rough, itchy, and inflamed skin that results in superficial cracking of the skin. Occurs most commonly during fall or winter months when the weather is dry. Most commonly appears on the abdomen, thighs, or shins.
Triggers:
Because eczema is inherited, there is no way to prevent the disease. But specific triggers can make pre-existing eczema worse or cause a flare to occur on normal skin. The triggers can be roughly divided into three categories: environmental, infectious, and emotional.
Environmental triggers:
External irritants and allergens may directly cause eczema to worsen. Controlling these environmental trigger can improve eczema or makes flares less frequent and severe. Environmental triggers can be subdivided into 2 categories:
1. Allergens, which make eczema worse due to stimulation of immune responses.
2. Irritants, which cause eczema to flare due to direct damage of the skin.
Allergens:
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Foods: Food allergies are more common in children with eczema than in children without eczema. However, it is still controversial whether food allergies make eczema worse. In children, foods reported to cause eczema flares include: eggs, peanut, milk, soy, fish, wheat, and rice. In food allergy-related flares, new skin lesions typically occur within twelve hours of ingestion. Many children outgrow food allergies, especially to eggs or milk, but nut allergies are lifelong. For adults with eczema, there is no clear evidence that food allergies make eczema worse.
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Fifty percent of children with severe eczema (skin lesions affecting greater than twenty percent of the body) have associated food allergies.
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Twenty-five percent of children with moderate eczema (skin lesions from five to twenty percent of the body) have associated food allergies.
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Most children with mild eczema do not have food allergies.
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Food allergies are best diagnosed by an allergist through blood or skin testing.
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Foods that are perceived to worsen eczema can be withheld but overly restrictive diets can lead to nutritional deficiencies. Discuss food restrictive diets with your physician.
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Dust mites: Allergies to dust mites can may eczema worse. Control dust mites by regular vacuuming of carpets and curtains and laundering of bedding. Use a plastic mattress and pillow cover to help reduce the house mite population. One helpful hint is to vacuum while the patient is away from the house.
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Animal dander: Patients may develop allergies to household pets such as cats or dogs.
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Irritants:
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Wool and coarsely woven materials: Children and adults with eczema have sensitive skin. Wool in particular may irritate skin and cause itching and skin irritation.
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Soaps: Harsh soaps and detergents remove the oils that are needed by the skin to maintain hydration. As a result, skin becomes dry and irritated, which often causes outbreaks of eczema.
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Temperature and humidity can be irritants. The following conditions tend to dry the skin or cause the skin to become itchy:
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Overheating and sweating
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Dry conditions in the fall or winter
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Hot baths or showers
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Infectious triggers:
Patients with eczema are more prone to certain infections. Sometimes the infections may trigger rapid spreading of eczema to involve large areas of skin. Over ninety percent of patients with severe, acute eczema (greater than twenty percent of body surface area involvement) will grow Staphylococcal aureus bacteria from skin cultures. Sometimes Staph. aureus infections are accompanied by small pus filled bumps (folliculitis) or crusting (impetigo) which are clues that an infection is present.
Emotional stress triggers:
Emotional stress and lack of sleep may exacerbate the itching and discomfort that accompanies eczema but generally do not trigger outbreaks.
Viral Infections Associated with Eczema:
Patients with eczema are more prone to certain viral skin infections such as warts or molluscum contagiosum. The majority of children with widespread molluscum also have underlying eczema. Patients with eczema are also prone to unusually widespread herpes simplex infections, a condition termed eczema herpeticum. In this condition, large areas of skin can develop small 1-2mm crusted sores that all look similar. In addition to itch, patient may complain of burning skin and develop fever.
Medical Treatment
In most cases, no single treatment is effective. The most effective treatment for eczema — regardless of type — involves using the combined approach of rehydrating the skin with moisturizers, reducing skin inflammation, and making lifestyle changes to avoid triggers. Although flares of disease may still occur, the flares tend to be less severe and resolve faster with treatment.
The type of medication prescribed will depend on many factors, including the type of eczema, the age of the patient, the amount of skin involved, past treatments, and the patient’s preference. Topical (applied directly to the skin) medication is most frequently prescribed. If the eczema is more severe, phototherapy (a type of treatment that uses light) or oral medication (taken by mouth) may be prescribed.
Topical Medications
The most common topical medication used to treat eczema is corticosteroid containing creams such as hydrocortisone. These types of steroid creams reduce inflammation and itch. They are not the same steroids use by some athletes to build muscle. In general, these medications are applied directly to the affected skin, twice daily. When used with moisturizers, topical steroids should be applied first.
Topical steroids vary in strength and using the wrong strength in a sensitive area can damage the skin. Your physician will prescribe an appropriate strength steroid to use based upon the location and size of the affected skin. Topical steroids are classified from weak (class VI) to ultrapotent (class I). The goal of topical steroid treatment is to relieve the inflammation and itch associate with eczema by using the least potent class of topical steroid possible. Using the appropriate strength medication helps prevent unwanted side effects. For instance, if clearance of eczema on the face can be achieved with a class VI steroid, a class I steroid is generally not prescribed. Once control is achieved, the topical corticosteroid can be applied less often or a lower strength steroid cream can be used to maintain long term control. Alternatively, your physician may stop the steroid cream altogether and restart the cream only when a new patch of eczema develops. It is important to not use a topical steroid prescribed for someone else.
Whether your medication comes as an ointment, cream, or lotion can affect how well the medication works. In general, ointments are more effective than creams and creams are more effective than lotions due to better absorption of the medication. Creams and lotions may sting when applied, which is generally not a problem with ointments.
Potential side effects of topical corticosteroid use include skin thinning and redness. In rare cases, normal growth can be temporarily affected in young children. To prevent side effects such as this, your physician may limit the length of treatment time and locations where treatment is applied.
In some cases, when topical corticosteroids and tacrolimus/pimecrolimus cannot be used or are not effective, specific types of tar or tar-derivatives may be made into a topical cream used to treat eczema.
Ceramide Replacement Therapy:
The skin of patients with eczema have an impaired barrier function. Normal skin is watertight but eczema skin is not. As a result, significant moisture is lost through eczema skin (termed "transepidermal water loss"). Analysis of the skin from eczema patients showed they lacked a critical lipid called ceramide, which helps maintain normal barrier function. Now, several new moisterizers are available with high levels of ceramide which can help the normal barrier function of eczema skin.
Over the counter moisterizers with ceramide include:
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CeraVe
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Triceram
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SkinMedica TNS Ceramide Treatment Cream
Prescription moisterizers with ceramide include:
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Mimyx
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Epiceram
Light Therapy:
For some older children or adults with severe eczema, ultraviolet (UV) light therapy (also known as phototherapy) may be used as a treatment for eczema, either as the sole treatment or in addition to other topical or oral medications. This type of therapy is done under the supervision of a dermatologist and often involves up to three treatments per week.
Oral Medications
The most common oral medications used to treat eczema are oral antihistamines. Antihistamines can sometimes help reduce severe itch. Because drowsiness is a common side effect, antihistamines are most often used at bedtime to help a person who is uncomfortably itchy from eczema to get a restful night’s sleep. Nonsedating antihistamines to reduce itch are sometime useful during the day. Over the counter antihistamines helpful for eczema include Benadryl (sedating), Claritin (nonsedating) and Zyrtec (nonsedating). Common prescription antihistamines include hydroxyzine (sedating) and Allegra (nonsedating).
For severe flares that involve large areas of skin, oral corticosteroids may be prescribed. However, frequent or long term treatment using oral corticosteroids is generally not recommended because of increased side effects with long-term use.
When severe eczema flares are accompanied by skin infection, usually by Staphylococcal aureus, oral antibiotics are helpful at treating the infection and clearing patches of eczema more quickly.
Guidelines for Skin Care to Prevent Eczema Flares
Adjusting your daily routine to one that promotes good skin care is the first line of defense in controlling eczema, regardless of whether your eczema is mild, moderate, or severe. Although even the best skin care may not prevent new flares from occurring, the flares will generally be less severe, last a shorter length of time, and respond better to treatment. In addition, keeping eczema in remission means apply less anti-inflammatory medications, which will reduce your chance of experiencing side effects.
Moisturize daily.
Moisturizing helps eliminate the dry skin which can cause eczema to flare. Moisturizers lock in the skin’s own moisture to prevent drying and cracking. The more oil a moisturizer contains, the more effectively it protects against moisture loss. Moisturizers that come in ointment form contain the most oil because an ointment consists of 80% oil and 20% water. This water-in-oil emulsion forms a protective layer on the skin and makes it more “moisturizing” than creams and lotions which contain more water and less oil. Moisturizers should be applied twice daily. At least one application should occur within three minutes of bathing to help seal in the moisture absorbed by your skin. When using moisturizers with topical corticosteroids to treat eczema, apply the corticosteroids first and the moisturizer second.
To learn more about moisturizing guideline see:
Avoid products and bathing routines that cause dry skin.
Strong soaps can worsen eczema because they dry out the skin. Use a soap containing a moisturizer or a skin cleanser specially formulated for dry or sensitive skin. Do not apply soaps directly on red, dry, itchy skin because that generally dries the skin even further.
Regular bathing can clean and hydrate the skin. But long, hot showers and baths will dry the skin and cause eczema to itch as the skin dries. It is recommended to bathe once daily for 5-10 minutes in warm (not hot) water.
For those patients with severe eczema, skin infections are a common problem. Most commonly, severe eczema develop staphylococcal infection. Bleach baths may help avoid frequent skin infection and are safe for use in infants, children, adolescents and adults. Common household bleach (approximately 1/4 cup) should be mixed in a 1/2 tub of lukewarm water and patients should soak for at least 10-15 minutes twice per week. Immediately after bathing, blot dry and apply a thick moisterizer (see above) or your prescribed topical medication.
To learn more about bathing guidelines see:
Avoid allergens.
Allergies can cause eczema to flare. If you suspect an allergy to be a trigger for your eczema, be sure to tell your physician. Tests can be run by an allergist to determine which, if any, food allergies exist or to assess for dust mite or other environmental triggers (animal dander, pollen). Food restrictions for food allergies should always be designed under the supervision of your physician.
To learn more about controlling dust mites and other precautions you can take around the house see:
Further read: Unlocking Human Skin Secrets, eczema included, in Dr. Julie Segre study is here.