Skin Prick Method - How Reliable Is It?

While a sizeable population suffers from allergy issues every year, treating them is often possible without an extensive diagnosis. However, the diagnosis of the allergen becomes crucial when the problem recurs several times in a year.

The skin prick testing is a reliable means of diagnosing the IgE-mediated (immunoglobulin E) allergic disease in people who have asthma, urticaria, rhinoconjunctivitis, atopic eczema, anaphylaxis, and drug allergy.

It offers evidence for confirming the diagnosis of the type I allergy. The best aspect of allergy testing by the skin prick method is that it is minimally invasive, inexpensive and the results are immediately available when carried out by trained professionals.

Why is the skin prick test conducted?
Skin prick test is usually used for diagnosing the food allergy symptoms which are typically caused by the interaction between a food allergen and the IgE antibody. To diagnose a food allergy, the allergy expert may recommend you undergo a skin prick test for measuring the number of antibodies present.

What can you expect?
During the skin prick test, the allergist places a drop of solution which contains the food allergen on the back or the forearm. When testing the fruits and vegetables, food is used in place of solution. In this allergy testing method, the doctor would use a needle or a plastic probe for gently pricking or scratching the skin for allowing a small amount of solution to penetrate the skin surface. This method is not painful, and no bleeding is involved in it. Though many people think that the process would cause much discomfort, the reality is that it feels similar to a scratch caused by fingernails.

On the basis of the case history, a patient may need to be tested for just one or many foods. The results are almost immediate; You can get them within half-an-hour of the test. The positive results of the test are indicated by a wheal which causes a raised white bump encircled by a small circle of itchy red skin. Though the size of the wheal is not the accurate indicator, a large wheal generally indicates that the patient is affected by food allergy.

How accurate is skin prick testing?
The skin prick allergy testing hardly produces any false negatives which indicate that you are not allergic to a food. Having negative results is synonymous with not being allergic to the food for which you are tested. On the other hand, positive results are also not always accurate. About 50 percent of cases show false positives which mean the positive result is shown even though you are not allergic to that particular food.

This simple test can be the means of identifying the allergens which will help determine the allergy prevention plan. Consulting an allergist before undergoing the test is essential.