Editing Allergy (section)

===Diagnosis===
Radiometric assays include the [[radioallergosorbent test]] (RAST test) method, which uses IgE-binding (anti-IgE) antibodies labeled with [[radioactive isotope]]s for quantifying the levels of IgE antibody in the blood.<ref name="pmid7630219">{{cite journal | vauthors = Ten RM, Klein JS, Frigas E | title = Allergy skin testing | journal = Mayo Clinic Proceedings | volume = 70 | issue = 8 | pages = 783–84 | date = August 1995 | pmid = 7630219 | doi = 10.4065/70.8.783 | url = http://www.mayoclinicproceedings.org/article/S0025-6196(11)64353-X/abstract }}</ref>

The RAST methodology was invented and marketed in 1974 by Pharmacia Diagnostics AB, Uppsala, Sweden, and the acronym RAST is actually a brand name. In 1989, Pharmacia Diagnostics AB replaced it with a superior test named the ImmunoCAP Specific IgE blood test, which uses the newer fluorescence-labeled technology.<ref name="n663">{{cite book | last=Mccarty | first=C. | title=Immunology: Essential and Fundamental | publisher=EDTECH | year=2018 | isbn=978-1-83947-284-8 | url=https://books.google.com/books?id=UePEDwAAQBAJ&pg=PA228 | access-date=2024-06-29 | page=228}}</ref>

[[American College of Allergy, Asthma and Immunology|American College of Allergy Asthma and Immunology]] (ACAAI) and the [[American Academy of Allergy, Asthma, and Immunology|American Academy of Allergy Asthma and Immunology]] (AAAAI) issued the Joint Task Force Report "Pearls and pitfalls of allergy diagnostic testing" in 2008, and is firm in its statement that the term RAST is now obsolete:

{{blockquote|The term RAST became a colloquialism for all varieties of (in vitro allergy) tests.  This is unfortunate because it is well recognized that there are well-performing tests and some that do not perform so well, yet they are all called RASTs, making it difficult to distinguish which is which. For these reasons, it is now recommended that use of RAST as a generic descriptor of these tests be abandoned.<ref name="Cox2008" />}}

The updated version, the ImmunoCAP Specific IgE blood test, is the only specific IgE assay to receive [[Food and Drug Administration]] approval to quantitatively report to its detection limit of 0.1kU/L.<ref name="n663"/>