Atopic dermatitis, often called atopic eczema or simply eczema, is a common condition affecting approximately 3 percent of the American population of all ages, and about 10 percent of all younger people between infancy and early adulthood. It eventually disappears in all but about 3 percent of people. In 70 percent to 80 percent of cases, there is a family history of one or more of the following allergic conditions: asthma, hay fever (or allergic rhinitis), hives, and atopic dermatitis. This suggests a family trait or genetic predisposition for the development of this problem.
To date there is still no conclusive proof that atopic dermatitis is an allergic disorder, but a fairly substantial amount of indirect evidence suggests that allergy plays a role, at least in some cases. For example, in about 10 percent of children, the disease can be triggered or worsened by allergic reactions to certain foods. Eggs, fish, milk, peanuts, soy, and wheat are common allergic triggers. Within as short a time as half an hour after consuming these foods, susceptible individuals may experience redness and itching. Merely stopping the culprit food often leads to complete clearing. Additionally, the link already noted between atopic eczema and asthma, hay fever, and hives is another strong piece of indirect evidence for an underlying allergic basis. Likewise, allergies to house dust and house dust mites have also been implicated in some cases. And finally, some researchers have recently found greater amounts of IgE antibodies (the so-called allergy antibodies) bound to the cells within the upper and middle layers of the skin of atopic individuals as compared with the skin of non-eczema-prone persons.
Nevertheless, nonallergic mechanisms are also believed to play a significant role in many cases. Dry skin, for example, often precipitates a flare-up of atopic dermatitis and is particularly troublesome during the wintertime due to the wet, chapping conditions of the outdoors and the drying condition of indoor heating. Summertime, too, has its difficulties because of the artificially lowered humidity from air-conditioning and the excessive dryness and irritation caused by the chlorine in swimming pools. And at any time of the year atopic dermatitis may be aggravated by the overzealous use of strong soaps and hot water. Finally, nervous tension and physical illnesses major ones as well as minor ones such as colds, fevers, sore throats, and ear infections are other well-known causes of flare-ups.
Diagnosis
The rash of atopic dermatitis is more likely to develop on the exposed areas of the skin, presumably because of the increased likelihood of chapping, drying, and environmental contact at these sites. In severe cases, however, the rash may occur anywhere on the body or even cover the entire skin surface. In young adults it typically involves the face, the folds of the elbows, and the backs of the knees, but it spares the groin. Affected patches are dry, scaly, reddish, and intensely and unrelentingly itchy (one of the hallmarks of the disorder). In chronic (persistent) cases, the involved areas eventually become lackluster, thickened, and brownish and are frequently covered with scratch marks and crusts.
In most instances dermatologists are able to diagnose atopic dermatitis fairly easily. It is strongly suggested in anyone with eczema who has a family and/or a personal history of asthma, allergic rhinitis, and hives. While there are no definitive tests for the condition, the finding of elevated blood IgE levels in someone with the skin manifestations of eczema is considered an additional support for the diagnosis.
Prevention
Given what has been said, susceptible individuals should take every precaution against overdrying and overchapping their skin. This means limiting showers to no more than three minutes at a time and using tepid rather than hot water. It is advisable to avoid washcloths and polyester scrub sponges, which unnecessarily abrade the skin, and to use mild synthetic detergent cleansers, as described above, instead of soaps that are pure alkaline, degreasing, deodorant, or abrasive. For those who absolutely cannot give up that nice, long, luxurious soak in the bathtub, I recommend the use of Alpha-Keri Bath Oil or Actibath Carbonated Tablets; they can be added to the bath water to offset some of the dryness. Whenever possible, choose garments made of pure cotton, especially intimate apparel, and select loose-fitting clothing rather than tight, constricting garments that rub the skin. Wool or other scratchy materials should be avoided since they can be especially irritating. In addition, wearing appropriate weather-protective clothing in the wintertime, getting plenty of rest, and trying to avoid colds also makes good sense under the circumstances.
Special effort must be made to protect the skin from drying. Shallow pans of water placed near radiators around the house or the use of cold air humidifiers are useful measures for reducing household dryness. If you enjoy chlorine swimming (beach swimming is generally better for the skin), you should coat yourself liberally with a hypoallergenic, all-purpose moisturizer before entering the water and once again immediately after rinsing off in the shower after swimming. For outdoor swimming, a moisturizing sunscreen such as Oil of Olay Daily UV Protectant is a reasonable choice. If additional moisture is needed, you might discuss with your doctor the use of the prescription-strength moisturizing lotion Lac-Hydrin for routine use and before and after swimming.
If a food allergy is believed to be contributing to the problem, your doctor may recommend a two-week trial of a nutritionally sound elimination diet, consisting of chicken (baked or broiled), lamb, rice, yams, broccoli, cauliflower, apples, and pears (cooked or canned), salt, and water. If improvement is seen during this time, the link to some food allergy is established. Thereafter, to determine the specific food culprit by looking for a flare-up, a new food group is usually reintroduced into your diet every four days. Breads, pastas, and cereals are generally added first, and other food groups are subsequently added slowly until the culprit foods are eventually discovered. The method may seem to be a long-drawn-out affair, but in the end it is more reliable than skin testing, which has a notoriously high rate of misleading results in cases of atopic dermatitis.
Treatment
Unfortunately, we are still unable to cure atopic dermatitis. Nevertheless, your dermatologist can prescribe a variety of simple measures and medications that will substantially alleviate your symptoms and clear up the rash. As in the case of other forms of eczema, the therapy for moderate and severe atopic dermatitis generally includes the prescription of topical corticosteroid creams alone or combined with oral antihistamines and, occasionally, brief courses of oral corticosteroids.
The use of topical steroids, especially high-potency agents, in atopic dermatitis, which is a long-term problem that may require years of therapy, demands a strong word of caution. While they may look like ordinary cold cream or petroleum jelly when applied to your skin, topical steroids should be used only under the strict supervision of a physician to prevent complications. If they are used on a daily basis for several weeks, the more potent classes in particular may cause irreversible, premature thinning of the skin, increased fragility, the development of "broken" blood vessels, skin pigment loss, and stretch marks. Used cautiously under a doctor's supervision, however, they are wonderful, neat preparations that offer sufferers welcome rapid relief.
Finally, in order to wean eczema patients from topical steroids once the rash has cleared and as part of a subsequent maintenance program to reduce the likelihood and severity of recurrences, I have found that, once again, Lac-Hydrin lotion is especially useful. Besides its value as a moisturizer, recent evidence suggests that it may have a protective effect against the skin-thinning effects of topical steroids when its use is alternated with the application of the steroid each day. Active research into atopic dermatitis promises still better and more specific therapies in the future.
