Eczema is a skin condition that causes the skin to become itchy, red and irritated. Besides these common symptoms some small liquid filled bumps may appear on the skin as well and these may become moist and ooze as well. There are several forms of eczema but atopic is the most common and severe form. It is also known as atopic dermatitis and is probably caused by the way a person's immune system reacts to different things/substances. Skin allergies may also be involved in some forms of eczema. Eczema may be an inherited skin condition. Other allergies (asthma, food allergies, animal dander, dust or fabric) may trigger or worsen eczema. Atopic eczema is difficult to diagnose as its symptoms are similar to contact dermatitis.
There are several types of allergy tests which can be used to diagnose allergies. The most common are the skin prick test and the blood test. The allergen-specific IgE antibody test is a blood test used to screen for an allergy to specific substances. Other tests include RAST test (also a blood test), challenges and intradermal testing. Skin tests are not 100 % accurate. People often test positive for a substance they are not allergic to at all. A patch test can be used to investigate contact dermatitis. This kind of test is used if the eczema is limited to a particular area such as the hands and face. This test can also be used to examine eczema that is getting worse or not responding to medical treatment. The patch test is carried out over three days in a week. On the first day, patients bring along suspected allergic causing substances which are stuck on the back. After two days, the patches are removed (the area must be kept dry during this time). On the third visit (the fourth day) a proper diagnosis is made. A red itchy patch will show an allergic reaction.
A radioallergosorbent test or RAST test is a blood test used to determine what substances a person is allergic to. It detects specific IgE antibodies to known allergens. The blood test measures the levels of the allergen IgE antibody to a specific allergen that is produced when the blood is mixed with a series of allergens. People suffering from severe eczema or who have a history of anaphylaxis are recommended to take blood tests rather than skin tests. This test is useful for children under five in particular where they are allergic to certain foods. On diagnosis, avoidance of these foods can help improve their eczema.
Submitted by M T on May 13, 2010 at 08:31