For Your Patients: How Will My Doctor Diagnose Atopic Dermatitis?

If you suspect that you or your child may have atopic dermatitis -- a chronic inflammatory skin disease that is the most common form of eczema -- make an appointment with your pediatrician or family doctor, or consider seeing a specialist such as a dermatologist or an allergist.

An accurate diagnosis is essential so that effective treatment is not delayed, and so you can feel better as quickly as possible.

During the visit, the physician will carefully examine your skin, or your child's skin, and ask a number of questions about overall health and symptoms. You can prepare for your appointment by taking a few minutes to jot down answers to the following questions:

Do any of your blood relatives have atopic dermatitis, or other allergies, such as asthma or hay fever?

Atopic dermatitis tends to run in families with a history of different kinds of allergies.

What are your symptoms?

The symptoms of atopic dermatitis include patches of dry, scaly skin, and an itchy, inflamed rash that feels warm to the touch. On white skin, the rash may appear red; on brown or black skin, it may appear more purplish or brown, with small, raised bumps.

Scratching can cause skin to crack and blister, leading to oozing and crusting, and increasing the risk of skin infection. Over time, scratching can cause skin to become thick and leathery. People with darker skin tones may also experience a gain or loss of pigmentation in the affected areas.

When did the symptoms begin?

About 60% of cases of atopic dermatitis develop in infants from the ages of 3 and 6 months, and 90% of cases develop in children by the age of 5 years.

Adults can also develop atopic dermatitis, even if they didn't have it as a child. Young adults in their 20s, middle-age adults in their 50s, and even seniors 65 and older can be diagnosed with atopic dermatitis for the first time.

Where is the rash?

Location is an important clue. In very young children, atopic dermatitis can develop on the scalp and face, especially on the cheeks, as well as on other parts of the body, including the hands and feet. It does not, however, develop in the diaper area, which is too moist.

In older children and adults, atopic dermatitis tends to develop in places where the skin is creased: the backs of the knees, the crooks of the elbows, as well as on the neck, hands, and feet. Lower eyelids may become darker and thickened due to chronic rubbing.

Have your eyes ever felt itchy, watery, or gritty?

In adults, atopic dermatitis can also develop on the eyelids and around the eyes, increasing the risk of an eye infection known as conjunctivitis or "pink eye." The eyes may take on a characteristic pink or red color, feel watery and itchy, and become sensitive to light. They may crust shut overnight. If not treated, atopic dermatitis affecting the eyes can become severe, and lead to more serious inflammation of the cornea or "keratitis." The eyes may feel gritty, as though there's something stuck in them, and become painful.

Do the symptoms come and go?

The itchy, inflamed skin that is associated with atopic dermatitis tends to disappear from time to time, only to reappear when triggered by allergens in the environment, or by certain foods, or even stress. Allergic triggers can bring severe itching and rash back in a flash, in an event known as a flare-up.

Diagnostic Tests

Your doctor may need to perform other tests to diagnose atopic dermatitis and determine the best way to treat it.

A skin prick test, or a skin patch test, may be performed to determine the full extent of any allergies you may have, and in certain cases, a skin biopsy may also be required.

Here's a quick rundown of what's involved.

• Skin biopsy: This can be quickly and easily performed during your appointment. A local anesthetic is used to numb a small area of skin, which is then removed for examination under a microscope

• Skin prick test: Even though you may have reported experiencing hay fever or asthma, a skin prick test will provide a better overall picture of any allergies you may have. You may be allergic to certain foods such as eggs, for instance, or to common allergens in the environment such as pollen, mold, and pet dander. These allergies act as triggers, making atopic dermatitis worse. To perform a skin prick test, a nurse or other healthcare professional will place a series of small liquid dots containing potential allergens on the inside of your forearm or on your back. Each liquid dot is then pushed under the skin with a needle. You will feel a small prick, but no pain. Within about 60 minutes, an itchy hive will appear next to any substance that triggers an allergic reaction

• Skin patch test: A patch test may help determine if you are sensitive to certain chemicals, rubber, metals, cosmetic ingredients, or foods. The test involves the placement of small patches containing various allergens on your back, where they stay for about 48 hours. Any patch that develops a rash underneath it signals an allergy

Read Part 1 of this series: For Your Patients: Atopic Dermatitis 101

"Medical Journeys" is a set of clinical resources reviewed by physicians, meant for the medical team as well as the patients they serve. Each episode of this 12-part journey through a disease state contains both a physician guide and a downloadable/printable patient resource. "Medical Journeys" chart a path each step of the way for physicians and patients and provide continual resources and support, as the caregiver team navigates the course of a disease.