Symptom Diagnosis
Itching, sometimes intense, is the hallmark symptom. With time the lesions tend to scale and flake and, if bacterial or viral infection is introduced by scratching, the affected lesions will ooze.

In infants, atopic dermatitis commonly appears on the face and in the creases behind the ears, at the elbows, behind the knees, and at the buttocks. When the face is involved, a prominent fold across the lower eyelids, called a Dennie's line, may appear. In children, the skin of the outer arms and legs may also be affected. Children and adults who have atopic dermatitis will develop a white, raised wheal when their skin is firmly stroked in an unaffected area by a tongue depressor or the back of a fingernail. This is termed white dermatographism (white writing), and is a maneuver used by a physician when the diagnosis for atopic dermatitis is uncertain. Other diagnostic tests which are helpful, when there is no family history of allergies and the child does not have asthma or nasal allergies, include a blood test for the quantity of circulating IgE antibodies, which are elevated in 80% of atopic dermatitis patients, and allergy skin tests. The latter are useful in identifying foods or inhaled substances such as house dust, dust mites, animal dander, or pollen to which the patient is allergic, and which may be responsible for flare-ups of skin lesions.
 

Treatment
If the patient reacts significantly to foods when skin is tested, these foods should be eliminated from the diet and the effect of their removal should be observed by the patient or the family. Should the skin improve and the itching lessen markedly, it would be advisable to re-introduce the suspect food or foods one by one while watching for a return of the original symptoms. If a food or foods are clearly the culprit, they should be removed completely from the diet. If the food is an essential food, such as milk in infants, your physician will be able to recommend non-allergic substitutes. If environmental factors are suspected, they should be dealt with similarly.

Itching can be minimized by bathing in tepid water and using unscented soap, patting (not rubbing) the skin to partially dry it, and applying a water-in-oil cream or lotion immediately. Steroid creams or ointments are useful for application to severely affected areas, but should not be applied to the face. Certain antihistamines are very helpful in relieving itching, and for children older than 12 years, non-sedating, long-acting antihistamines are especially desirable.

To improve the symptoms, fingernails should be kept short and clothing fabrics should be soft and porous when possible. Laundry detergents should be mild and free of perfumes. If there is oozing from the affected skin areas, the patient should consult a physician, since antibiotic treatment may be necessary.
 

Prognosis
A 21 year follow-up study showed that, of children who developed atopic dermatitis in infancy, about 30% had no skin problems and had not developed other allergic disorders. Twenty-one years later, 35% had no skin lesions but had developed asthma and/or hay fever; 20% still had atopic dermatitis; but only 15% had persistent dermatitis plus asthma or hay fever. However, it is not clear how diligently these patients followed recommendations. It is unlikely that strict observance of dietary, environmental and therapeutic measures might have produced even better long-term results.