Types of Allergy Testing, Their Benefits and Disadvantages

To identify the hypersensitivity, a few steps should have been taken. The first is the anamnesis, or patient history – in which the specialists delineates the patient for his or her hypersensitivity manifestations when they occur, and how extreme they are. The specialists will ask the patient few queries concerning whether the individual is taking medications,what the living conditions are, and whether there are any acquired conditions. However, the anamnesis isn't satisfactory for the conclusion. Therefore, additional tests ought to be performed. The manifestations and diverse factors figure out which test should be taken out.

Sensitisation tests, for instance, skin tests or blood tests reveal whether the body is slanted to hypersensitivity to specific substances or not. A skin test is commonly performed for confirmation. Blood tests are particularly significant for cases, for instance, when skin testing is laborious due to the skin condition. There are three types of tests which should be generally considered are:

• Patch Test
• Skin Prick Test
• Blood Test

Patch Test

It is normally performed in order to analyze hypersensitivities to various allergens. These tests are used to inspect a sort of skin aggravation known as contact dermatitis, which can be caused by your skin being exposed to an allergen. A little measure of the assumed allergen is added to metal plates, which are then taped to your skin for 48 hours and observed for a reaction.

Basic information about Patch testing :

• Do not apply any oil or cream on your skin before testing
• Keep the area of skin being tested dry until the last observation.
• Avoid bending because that can lift the test patches.
• Evade medicaments because it can interfere with patch testing.

Disadvantages:

• Aggravates the skin condition
• The medications taken by the patient may meddle with patch testing

Skin Prick Test

Placing a small amount of allergen on the skin, generally on the lower arm, upper arm, or back. The skin is then pricked with a small, sterile probe so that the allergen goes under the skin's surface. This testing is not painful, and generally, there is no bleeding involved since the needle only scratches the surface of the skin. The specialists simply observes the skin for swelling and redness or some other hypersensitive manifestations. After the skin is scratched, the results are commonly seen within 15 to 20 minutes. A positive skin test shows up as a raised, red irritated knock, like a mosquito nibble. As a control, you'll also get a skin prick with a liquid that doesn't contain the allergen; this should not provoke a response, permitting comparison between the two test sites.

Benefits :

• Less costly
• Rapid results

Disadvantages:

• It can trigger a more serious type of allergic reactions in some individuals.
• It cannot be performed on some individuals having serious skin inflammation.
• It can interfere with the medication taken by the individual.

Allergy Blood Test

Allergy blood tests are used to see whether you have an allergy. One sort of test called total IgE test estimates the overall IgE antibodies in your blood. Another sort of sensitivity blood test called specific IgE test appraises the level of IgE antibodies in response to individual allergens. Allergy blood tests recognize and measure the amount of allergen-specific antibodies in your blood. When you come into contact with an allergen, your body makes antibodies against it. The antibodies exhort cells in your body to release certain synthetic substances. These chemicals leads to various allergic manifestations. Immunoglobulin E (IgE) is an immunizer that is associated with the body's allergic response. Hypersensitivity blood tests screens the most well-known allergic triggers, including dust, pet dander, trees, grasses, pollens, and structures related to where you live. They are also particularly strong in diagnosing food hypersensitivities. A positive result suggests allergy specific antibodies were distinguished in your blood. This is commonly a symptom of allergy. The blood test will reveal what accurately you are antagonistically affected by. Regardless, you can test positive for something yet never have had a negatively allergic reaction to it. A negative result infers that most likely you don't have an authentic allergy to any allergen. That infers your immune system likely does not respond to the allergen tried.

Allergy blood testing is suggested if you:

• are utilizing a medication known to meddle with test outcomes and can't quit taking it for a couple days this would incorporate antihistamines, steroids, and certain antidepressants.
• Cannot endure many needle scratches required for skin testing
• Have extreme skin inflammation, dermatitis, psoriasis, or another serious skin condition
• Might have an extraordinary reaction during skin testing or have a history of anaphylaxis.

Allergy blood test is most commonly used because:

• The patient may be on medication that can meddle with skin testing, and can’t be quit for few days.
• Testing with a strong allergen may cause a huge positive reaction.
• The patient may be suffering from a serious skin inflammation.