How will your healthcare professional find the cause of your hand eczema?
Your healthcare professional may start by asking you if you have noticed anything in particular that you think may be causing your hand eczema. They may also ask about your job, your daily life and if there has been a change in either that seems to have triggered your hand eczema.
Skin prick tests
To find out whether your hand eczema is caused by an allergen (a substance that causes an allergic reaction), or an irritant (a substance that can damage the skin), your healthcare professional may perform a skin prick test on you. They are a quick and reliable way of detecting whether you are sensitised to a common allergen. These tests are usually carried out on the inner forearm or back, where small drops of allergen solution are pricked into the outer layers of the skin. It is slightly uncomfortable, but no worse than having a hair plucked. If you are allergic to the allergen, you will develop a small, red, itchy swelling.
Allergy blood tests
Allergy blood tests are carried out in a laboratory, and the results may not come back for a few weeks. They are simple tests, but the person performing them needs to be very skilful in interpreting them properly as they can pick up low levels of allergic reactions that don’t actually cause a visual problem. Such results are known as ‘false positive’ results and occur more often when testing people who have atopic eczema.
Patch tests
Patch tests have been used for over 100 years to diagnose allergic contact (eczema caused by an allergy to a substance). If you have recently developed eczema, if you have unusual eczema, or if your eczema won’t go away, your Dermatologist may suspect that you have allergic contact eczema. Patch testing is the only way to prove that a specific substance is causing your eczema or making it worse. Before your doctor performs a patch test on you, he or she may ask you questions to help determine what may be causing your eczema. These may include what skin products you use, what treatments you have tried, what you do for a living, what your hobbies are, where and how your eczema began, and what the general health of you and your family is. Patch tests should be carried out on skin that is not affected by eczema, usually on the back, the upper arms or the chest. Small amounts of suspected allergens are placed against the skin and covered with sticky pieces of tape - the patches - so that the allergens are absorbed into the skin. After two days, the patches are removed, and the skin is inspected. If the allergen that causes your eczema has been amongst those tested, the skin should develop as a small, red, itchy, swollen patch of skin. If your allergy is strong, the skin may also blister and weep. If you are not allergic to a test allergen, there will be no effect on your skin. Your doctor may want to examine you up to three times in case your skin takes more than a couple of days to react to the allergen. You will not be able to play vigorous sport or wash the test area during the investigation. You will, however, be able to wash the rest of your body as long as you are careful not to disturb the tested area of skin until the last reading has been taken. You also shouldn’t expose the patches to ultraviolet light, including sunlight, while the testing is taking place.
Tests to determine whether you have allergic contact eczema may sound daunting, but they aren’t really.
If you are going to see a healthcare professional about your hand eczema, it’s all too easy to forget all the things you’d like to ask. Don’t forget to visit the ‘Downloads’ section of this website for useful questions to ask during your appointment.
