Tests and diagnosis of eczema
There is no single test that is used in order to diagnose eczema.
The doctor may need to see a patient multiple times in order to make an accurate diagnosis. This is because people with eczema experience very individual combinations of symptoms, which tend to fluctuate in severity over time.
Diagnosis is based primarily on the patient's symptoms, but medical history is also important. A doctor will often ask about a patient's family history, other atopic diseases such as asthma and hay fever, possible exposure to irritants, whether any foods are related to flare-ups, sleep disturbances, past treatment for skin symptoms and the use of steroids or other medications.
A doctor may refer a patient onto either an allergist or dermatologist for further evaluation.
They may also attempt to rule out other conditions that can cause skin irritations. This can involve the following tests:
Patch testing: substances are placed onto the surface of the skin to test for skin allergies
Skin prick testing: a needle containing a small amount of a suspected allergen pricks the skin to test for allergies that do not necessarily occur on the skin, such as pollen or food.
Supervised food challenges: foods are eliminated and then introduced into the diet to determine whether a food allergy is present.