Course and Prognosis
Atopic dermatitis is a chronic disease characterized by exacerbations and remissions. A few patients have a single episode and then remain clear indefinitely, but for most individuals, once the initial episode has occurred, future problems may be anticipated.
Individual episodes of atopic dermatitis left untreated generally continue chronically. Treatment, on the other hand, is usually quite successful and may lead to prolonged periods of remission. The initial episode of atopic dermatitis often occurs during childhood, and most, but not all, patients will have had their first episode by age 35.
Patients with atopic dermatitis are at considerable risk of developing the noncutaneous atopic diseases of hay fever and asthma. There is also evidence to suggest that these patients are more likely to develop alopecia areata, vitiligo, otitis media, nrticaria, and dyshidrosis, but many authorities doubt the validity of these relationships.
Patients with atopic dermatitis, as a reflection of the mild depression of cell-mediated immune responsiveness that accompanies the disease, are also more likely to develop cutaneous fungal and viral infections. Moreover, these infections when present may be unusually severe, For instance, atopics are at considerable risk for the development of disseminated cutaneous herpetic infection in the syndrome known variously as Kaposi’s varicelliform eruption or eczema herpeticum.
Staphylococcal organisms regularly colonize the lesions of atopic dermatitis. Interestingly, in spite of the large number of organisms that are present, clinical signs of true infection are not often found.
Therapy
One absolute rule exists regarding therapy of atopic dermatitis: scratching must be stopped. Therapy that fails to interrupt the itch-scratch cycle will not lead to consistent, prolonged clinical improvement.
Soaks are of help in the treatment of acute episodes accompanied by weeping and crusting. Such soaks serve two purposes. First, they restore a more physiologic environment to the sensory nerve endings. This result presumably reduces nerve stimulation, which, in turn, decreases the transfer of itch sensations to the brain. Second, by removing crust, maceration is reduced and bacterial overgrowth is minimized.
Topically applied steroids are almost indispensable in the treatment of atopic dermatitis. Infants and adults with involvement of the face and groin should be treated with low-potency products such as 1 % hydrocortisone whenever possible. In other areas of the body higher potency products will be required. Cream vehicles are generally used because of easy spreading and cosmetic acceptability. If stinging on application is a problem, however, ointments can be substituted.
If ointments are used, they should be applied sparingly and should be spread as thinly as possible in order to minimize sweat retention and the development of maceration.
Patients with severe or extensive disease may initially require a burst of prednisone . Clinical response is extraordinarily good, but rapid exacerbation can be expected unless a good topical program is also being conscientiously carried out. Failure to recognize this point defeats the rationale for the short-term use of systemic steroids.
Systemically administered antihistamines are often necessary to help control pruritus. Part of their effectiveness is due to inhibition of intlammatory mediators, but an additional, more important component undoubtedly relates to their central nervous system effect as manifest by the presence of sedation. In fact, I believe that tranquilizers and other sedatives reduce pruritus about as well as antihistamines. Because of the sedation associated with most of these agents, they are generally best administered in the evening. Dosage should be adjusted to the point where, because of deeper sleep, nighttime scratching is stopped.
UVA (320- to 400-nm) and UVB (280- to 320-nm) ultraviolet light therapy and psoralen-long-wavelength ultraviolet light (PUVA) therapy can be very helpful in controlling pruritus. Of course, care must be taken to avoid sweating, burns, and excess dryness as a result of such therapy, since these factors may instead increase the severity of the itching.
Long-term lifestyle adjustments to reduce stress and increase relaxation are necessary in some cases and are particularly helpful in tense patients who cannot easily relax. Some of these adjustments occur as the patient develops insight, but counseling or behavior modification techniques such as vigorous athletics, transcendental meditation, yoga, hypnosis, and biofeedback are often necessary.
Modifications in routine skin care are highly desirable. Lubricants retard moisture loss from superficial epidermal cells, this reduces the nerve stimulatioll that occurs through dry, chapped skin. Hands should be lubricated 4 to 6 times/day, full-body lubrication should be carried oul twice daily.
Fingernails should be trimmed and rounded with a file so that no sharp edges remain. Hot water bathing and the use of soap must be decreased as much as possible, since both remove lipids necessary to keep the skin from becoming xerotic. The use of cotton clothing minimizes the deleterious effect of sweat retention, and wool clothing should be avoided, since the prickly wool fibers tend to have an irritating effect on atopic skin. Patients should, where possible, set room temperatures at a level that prevents heat buildup and sweat production. Finally, the use of alcoholic beverages as a means of inducing rapid relaxation should be discouraged, as alcohol in large amounts decreases the soundness of sleep later at night and in the early morning.
The therapeutic program described above is representative of the way most clinicians care for patients with atopic dermatitis. Three additional approaches favored by some dermatologists ought to be mentioned. The first is the modified Scholz regimen, which avoids all use of soaps and lipids. Cleaning is carried out with a nonlipid cleanser such as Cetaphil. Cetaphil lotion is also used as the vehicle for all medications.
The second approach substitutes coal tar products for topical steroids wherever possible. This avoids the potential side effects of steroids and is also quite inexpensive. Unfortunately, improvement occurs rather slowly, and patient compliance is poor because of the staining and odor associated with tar products.
The third approach involves the routine use of systemically administered antibiotics whenever weeping or crusting is present on the surface of the skin. Advocates of this approach believe that the bacteria that grow readily on eczematous skin (independent of the amount of true infection caused) play a role in the pathogenesis of the disease. The use of antibiotics does sometimes speed up healing but, of course, also raises the potential problem of eventual bacterial resistance.
Finally, mention should be made regarding the emerging use of cyclosporine . European reports suggest that it can be used safely and very effectively as short-term treatment.