Possibilities of an allergy test

If you have noticed a slight tingling in your nose or itching or the like during an examination with contrast media, a test can be used to check whether an allergy is actually present. This test is usually carried out as part of a so-called prick test. In the prick test, the skin of the forearm is pricked several times on the surface using a small stick.

Then various allergens are applied to the individual areas. If an allergy is present, the skin reddens where the allergen is located, causing wheals and itching.The prick test is positive if the contrast agent allergy is an immediate type reaction (type I allergy), i.e. if the symptoms occurred relatively soon after the administration of contrast agent. However, if the allergic symptoms do not appear until after 12 to 72 hours, it is more likely to be a type IV allergy (late type).

This can be detected by an epicutaneous test. In this test, various allergens are applied to the skin of the back. This area is then covered with special plasters.

After 48 and 72 hours, a check is made to see whether a local allergic reaction has occurred in this area. In principle, a provocation test with the allergen can also be carried out intravenously. Since this involves more risks than the other two methods, the provocation test is not usually used. and allergy test

TreatmentTherapy

In most cases, no further treatment is required for the allergic symptoms that have occurred, as they are often only mild and disappear on their own. Cortisone preparations and/or antihistamines can be used as support against the allergic reaction. If an allergic shock occurs, this is a potentially life-threatening emergency and should be treated as soon as possible.

The affected person should be placed in a shock position with the person lying flat on their back and their legs elevated. If the anaphylactic shock occurs immediately during the administration of the contrast medium as an immediate reaction, the administration of the contrast medium should be stopped immediately. Drug therapy for anaphylactic shock involves the administration of adrenalin and cortisone.

Like the contrast medium, the drugs are administered via the vein. In addition to adrenaline and cortisone, antihistamines and the administration of an intravenous fluid are often used. In addition to the drugs, a supporting oxygen administration via a mask is often necessary.