Severe and slight allergies can be defined basically by the patient’s reactions. Slight allergies may be seen that are described as bloating, diarrhea, vomiting and mild urticaria. More severe allergies may include shortness of breath, throat thickening and hypotension.
It is difficult to determine which tests may predict the severity of the allergic response.
Scratch testing is a very specific evaluation tool. A positive scratch test will most likely be clinically significant. A negative scratch test may be a false negative. This is a definition of specificity. A blood test or a RAST test or CAP test has increased sensitivity but less specificity. These types of tests may have false positives. As you can see, there is probably no test that is completely accurate.
Using the tests in tandem, we can define an allergy based on the patient’s clinical history.
Some CAP tests have been evaluated for their ability to predict severe allergic reactions. The antigens that have been determined include peanut, milk and egg.
The difference between a mild and severe allergic reaction is based on the patient’s clinical symptoms. Close discussion with your allergist will help you understand the evaluation process.
