II. Mechanism: Assays

  1. RadioAllergoSorbent Test (RAST)
    1. Older methodology
    2. ImmunoCAP has largely replaced the older RAST methodology
  2. Enzyme-linked Immunosorbent Assay (ELISA, most common)
  3. Fluorescent Enzyme Immunoassay (FIA)
  4. Chemiluminescent Immunoassay

III. Efficacy

  1. Highly specific for allergens
  2. Lower Test Sensitivity than allergy Skin Testing

IV. Indications

  1. Not recommended for food, venom, or drug allergies unless high risk for Anaphylaxis
  2. Alternative to Skin Testing in certain cases
    1. Skin Testing contraindicated
    2. Interfering medications (e.g. Antihistamines)
    3. Age <3 years
  3. Allergy Testing for common allergens
    1. Pet dander
    2. Dust mites
    3. Pollen
    4. Mold spores

V. Approach: Screen Contents

  1. June Grass and cross reacting grasses
    1. Rye
    2. Sweet Vernal
    3. Timothy
    4. Brome
  2. Oak Tree
  3. Short ragweed
  4. Alternaria mold
  5. Dust mite
  6. Cat

VI. Technique

  1. Allergen coupled to a paper disc
  2. Patient's serum is added to paper disc
  3. Antigen-Antibody forms in the case of allergy
  4. Radioactive anti-IgE added and complexes with above
  5. Gamma counter scores binding

VII. Interpretation: RAST Scoring

  1. Class 0: 200-750 (No significant allergy)
  2. Class 1: 750-1600 (Mild allergy)
  3. Class 2: 1600-3600 (Moderate allergy)
  4. Class 3: 3601-8000
  5. Class 4: 8001-18000
  6. Class 5: 18001-40000 (Most allergic)

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Related Studies

Ontology: Radioallergosorbent Test (C0034554)

Definition (NCI) A type of blood test used to test for allergies.
Definition (MSH) An in vitro allergen radioimmunoassay in which allergens are coupled to an immunosorbent. The coupled allergens bind the IgE in the sera of patients which in turn binds radioisotope-labeled anti-IMMUNOGLOBULIN E antibodies.
Concepts Laboratory Procedure (T059)
MSH D011852
SnomedCT 69214006, 143398009, 166022006, 397587005
LNC LP6477-6
English Allergens Radioimmunosorbent Assay, Allergens Radioimmunosorbent Assays, Radioallergosorbent Test, Radioimmunosorbent Assay of Allergens, Test, Radioallergosorbent, Tests, Radioallergosorbent, Radioallergosorbent Tests, EAST test, RAST-Radio-allergosorbent test, radioallergosorbent test, rast test, east test, radioallergosorbent testing, rasts, Test;RAST, rast testing, rast tests, rast, Radioallergosorbent test, RAST - Radio-allergosorbent test, Radio-allergosorbent test, RAST test, Radioallergosorbent test (procedure), Radioallergosorbent test, NOS, RAST test, NOS, RAST
Italian Test di radioallergoadsorbimento, RAST, Prova di radioallergoassorbimento
Portuguese Prova radialergabsorvente, Teste de Radioalergoadsorção, Testes de Radioimunoensaio para Alérgenos, RAST, Teste radioalergoabsorvente
Spanish PRAA, Prueba de Radioalergoadsorción, Prueba de Radioinmunoadsorción de Alérgenos, prueba RAST, Test de Radioalergoadsorción, Ensayos de Alérgenos Radioinmunoadsorbente, RAST, prueba radioalergosorbente (procedimiento), prueba radioalergosorbente, Prueba de radioalergoabsorbente
Japanese RAST, 放射性アレルゲン吸着検査, RAST, ホウシャセイアレルゲンキュウチャクケンサ, 放射性アレルゲン吸着試験, アレルゲン放射性免疫吸着分析, ラジオアレルゴソルベントテスト, 放射性アレルギー吸着試験, 放射線アレルギー吸着検査法
Swedish Radioallergosorbent-test
Czech radioalergosorpční test, RAST, Radioalergosorbentní test
Finnish Radioallergosorbenttitesti
French RAST (RadioAllergoSorbent Test), Test RAST, Test radioallergosorbent, Test radioimmunosorbent d'allergènes, Test radioallergosorbant, RAST
Polish Próba radioalergosorbentowa
Hungarian Radioallergosorbent vizsgálat, RAST (radioallergosorbent teszt)
Norwegian RAST, Radioallergosorbent test
Dutch radioallergosorbent test, RAST, Radio-allergo-sorbent-test, Test, radio-allergo-sorbent-
German RAST, Radio-Allergo-Sorbent-Test, Radioimmunosorbent Assay auf Allergene

Ontology: Allergen specific IgE antibody measurement (C1306725)

Concepts Laboratory Procedure (T059)
SnomedCT 69214006, 104381000
English IgE - Specific IgE test, IgE - Specific immunoglobulin E test, Specific immunoglobulin E test, Allergen specific immunoglobulin E antibody measurement (procedure), Allergen specific IgE antibody measurement (procedure), Allergen specific immunoglobulin E antibody measurement, Allergen specific IgE antibody measurement
Spanish medición de anticuerpo IgE específico de alérgeno, medición de anticuerpo IgE alergoespecíficos (procedimiento), medición de anticuerpo IgE alergoespecíficos, medición de anticuerpo IgE específico de alérgeno (procedimiento), medición de anticuerpo IgE específico de alérgenos