SPT is the most common allergy test performed in an allergy clinic by specially trained staff. SPT is a simple, safe and quick test, providing results within 15-20 minutes. pricking the skin with a needle or pin containing a small amount of the allergen.It is the primary mode of skin testing for immediate IgEmediated allergy. It is widely practiced, carries very low (but not negligible) risk of serious side effects to patients and provides high quality information when performed optimally and interpreted correctly. Also called prick skin testing or PST. Skin prick testing provides information about the presence of specific IgE to protein and peptide antigens. Small amounts of allergen are introduced into the epidermis and …show more content…
Comparison of test devices for skin prick test 2005 ]
Many practitioners leave the drops on the skin until the test is ready to read but this is probably not necessary; the test solution can be blotted from the skin after pricking without compromising the eventual result. The allergen extract is placed into small wells in a multi-well tray. The dropper (Duotip, Stallerpoint, Multitest) is dipped into the allergen extract, withdrawn, and then applied to the skin with firm pressure With the Duotip some advocate twisting the lancet to slightly shear the two tips into the skin and allow more allergen to penetrate.
Patient age:
There are no strict age limits but skin reactions are often diminished in the very young and the elderly, making interpretation more difficult in both cases. Infants often show larger flares and smaller wheals. Systemic allergic reactions may rarely occur in response to skin testing in infants. Because of increased risk and greater complexity of interpretation, skin prick testing below the age of 2 years should be considered a specialist practice. [ Roberts G, Lack G. Diagnosing peanut allergy with skin prick and specific IgE testing, 2005-2007