WHY ARE ALLERGY TESTS PERFORMED?
A dermatologist performs an allergy test to see if the patient’s immune system overreacts to some allergens. If there is an allergic reaction, the patient has an allergy. Often, a dermatologist will suggest an allergy test, if the patient has asthma – the test can show which allergens can make asthma symptoms worse or cause an asthma attack.
The patient also needs an allergy test if they’ve had an anaphylaxis or a major allergic reaction. The patient’s medical history together with an allergy test can determine the cause of this serious reaction.
If the patient is allergic to dust, pet dander, pollen or other air allergens, they might develop allergic rhinitis or hay fever. The symptoms include headache, watery and itchy eyes, sore throat, sneezing, runny nose or nasal congestion, wheezing, cough or shortness of breath.
In the case of food allergies, the symptoms generally happen 30 minutes after food ingestion or up to 2 hours. The symptoms will be swelling of the lips, tongue or face, itching and hives, respiratory symptoms like shortness of breath, coughing, wheezing or throat tightness, GI symptoms like cramps, abdominal pain, vomiting, nausea or diarrhea and cardiovascular symptoms like weak pulse, pale skin or dizziness.
If the patient is allergic to latex or metals like nickel, they may develop contact dermatitis or other symptoms like hives and swelling, blisters, rash and itchiness or burning sensation on the skin. These allergic reactions are determined with the use of a patch test.
WHAT ARE THE DIFFERENT TYPES OF ALLERGY TESTS?
Allergy tests are performed to determine which allergens or allergy triggers cause the body to overreact to them. The tests identify if the patient’s immune system produces antibodies called immunoglobulin E or IgE. These antibodies are also known as proteins whose chemicals trigger allergic reactions.
There are different ways to perform allergy tests. The dermatologist chooses the most effective test based on the patient’s allergy symptoms.
Patch test – this test can identify the cause of contact dermatitis. The dermatologist introduces droplets of various allergens onto the patient’s arm and puts a bandage over the droplets. Or the dermatologist can place a bandage that is already filled with allergens. The patient keeps the bandage for up to 96 hours when the dermatologist removes the bandage to identify if the patient’s skin has developed a rash or other symptoms of applied allergens.
Blood/IgE test – If this test is necessary for identifying allergies, the patient needs to get a blood sample tested in the laboratory. The allergens are introduced into the patient’s blood sample and levels of IgE antibodies are then measured. Sometimes, blood allergy tests can show falsely positive or negative results.
WHAT ARE THE BENEFITS OF ALLERGY TESTING?
Allergic reactions vary from mild like nasal congestion to severe like anaphylactic shock. Therefore getting a proper allergy test can make the patient’s life much easier.
There are many benefits of allergic testing.
Allergy test show allergens that trigger allergic reactions so the patient can treat and control those reactions properly. Some treatments include changing diet or avoiding other allergens.
For example, the patient can change his/her diet by avoiding the whole food group that triggers allergic symptoms. The patient can still have a nutritious diet with the rest of the food groups.
After allergy tests, the patient knows which allergens cause his/her allergy reactions and can avoid them. For example, if the patient finds out that they are allergic to animal dander, they may change their mind about having a pet.
When the patient discovers that they are allergic to environmental and air allergens, they can take the medications only when these allergens are high in the air and not all the time. For example, if the patient is allergic to pollen, extensive exposure to it should be avoided in the summer when this allergen is the highest. Also, grass pollen is the major allergen that causes hay fever. Or if the patient is allergic to tree pollen, exposure to it should be avoided in the spring when this allergen is the highest in the count.
Overall, the biggest benefit of getting an allergy test is preventing the risk of developing severe allergic reactions.
WHAT DIFFERENT TYPES OF ALLERGY TESTS EXIST?
Allergy tests are done to measure the patient’s body reactions to different allergens or allergy triggers. They show if the patient’s immune system overreacts and produces antibodies known as immunoglobulin E or IgE. These antibodies or also called proteins release the chemicals that trigger allergic reactions.
Allergies can be tested in different ways. The dermatologist determines which test is the best according to the patient’s symptoms and possible allergens.
Intradermal skin test
This allergy test is done if the skin prick test results are inconclusive or negative. The dermatologist injects a tiny amount of allergens into the patient’s epidermis or top layer of the skin. This way, the dermatologist can determine if the patient is allergic to insect stings, some medications or airborne allergens.
Patch test
This allergy test is performed to determine the origin of contact dermatitis. The dermatologist administers drops of allergen onto the patient’s skin on the arm and places the bandage over the treated area. Or the dermatologist applies a bandage that already has allergens on it. The patient needs to keep the bandage on the skin for up to 48 hours. After that, the dermatologist takes off the bandage to see if the patient’s skin has a rash or other reactions to applied allergens.
Blood/IgE test
For this allergy test, the dermatologist sends a sample of the patient’s blood to a laboratory. The allergens are added to the blood sample and levels of IgE antibodies are measured. In some cases, blood allergy tests can be falsely positive or negative.
WHY ARE ALLERGY TESTS BENEFICIAL?
Allergic reactions can be mild like congestion but also severe like anaphylactic shock. The dermatologist can choose the most suitable allergy test for each patient.
The benefits of allergic tests are numerous.
They can help the patient find a proper treatment solution because allergy tests can show the precise allergens that cause allergic reactions. The patient can change his/her diet or avoid environmental agents that cause his/her allergies and improve his/her quality of life.
Changing diet usually means avoiding the entire food groups that can trigger an allergic reaction. But this doesn’t mean that the patient can’t keep a nutrition diet with other food groups.
Once the patient knows what he/she is allergic to, he/she can avoid situations that can trigger these reactions. For instance, if the patient is allergic to animal dander he/she may reconsider the idea of having a pet.
When the patient is allergic to environmental allergens, he/she can only take medications periodically when these allergens are high in count. For example, pollen is high in the summer and grass pollen is the biggest cause of hay fever. On the other hand, tree pollen is the highest in the spring.
The most important benefit of an allergic test is that the patient can prevent the risks of serious allergic reactions.
