When the symptoms of eczema show themselves on your skin, it is important to schedule a visit with the doctor to determine what the problem is. Common medical testing will help to identify whether your skin condition is eczema or something else. An initial diagnosis of eczema is usually made based on what the skin looks like. Certain areas of the body are considered to be “eczema sensitive areas” such as the face, skin creases and the chest. If skin in these areas of the body is red, dry, itchy or swollen this may lead doctors to believe that eczema is the cause.
Doctors will discuss many other aspects of a patient’s life in order to form a better idea of what is going on. Other items that need to be considered are a patient’s family history (and other allergic related diseases in the family such as asthma or hay fever), lifestyle, dietary habits, tendency towards certain allergies (or any or all known allergies), prescription drugs the patient is currently taking and any chemicals or otherwise hazardous materials that the patient is exposed to either in his/her home environment or place of work. Other necessary pieces of information a patient should share with his or her physician include when the skin condition first made its appearance; all of the signs and symptoms of the condition, including itching or recurrent redness and inflammation; circumstances under which the skin condition is made worse, such as a high level of stress, excessive sweating and/or very dry air and a thorough medical history.
If a doctor suspects that a skin flare-up is due to an allergen then he or she will call for a blood test to check for any antibodies in the blood as well as the quantity of a variety of kinds of cells. If eczema is the cause of the symptoms, then the patient’s blood will show a raised “IgE” (or an eosinophilia). Sometimes the blood also needs to undergo a test known as a Radioallergosorbent Test (or RAST) or a Paper Radioimmunosorbent Test (PRIST). This test is done by mixing the blood separately with a variety of different allergens and then the level of the antibodies are measured carefully. Blood that is shown to have a great deal of antibodies in it means that there is definitely an allergy to a certain thing.
Some physicians will order a special test known as a skin patch test. In this case when something is suspected to be the source of the problem (i.e. an irritant to the skin) it is pressed to the skin and then held there with an adhesive patch. Another adhesive patch that is devoid of anything on it is also applied as a source of comparison. The irritant patch is left in place for anywhere from one day to two days. After that period of time it is taken away and the skin is examined. If the skin shows to be red, itchy and/or inflamed then more than likely it is the said irritant that the patient is allergic to.
On occasion a doctor will decided that the patient must have a skin lesion biopsy. This is when a small part of the skin is removed and then is sent to a lab to be viewed under a microscope. Biopsies as well as blood are not undertaken in every case where eczema is suspected. However they are often done when the symptoms are severe or out of the ordinary.