Alternative name
RAST
Description
The presence of significant levels of specific IgE antibodies to defined allergens in conjunction with a relevant clinical history is suggestive of IgE mediated allergy. IgE antibodies to over 1000 different allergens can be measured.For allergy testing. Request must specify which allergens should be tested based on clinical history.The laboratory is happy to suggest appropriate testing. Please provide as much clinical information as possible.
Indication
Identification of IgE to allergens responsible for allergic disorders.
Interpretation
See Allergy testing General Information
Sample
Serum Separator Tube (SST)
Assay details
Fluorescence enzyme linked immunoassay (Phadia Immunocap 250).
Restrictions
Less frequently requested allergens are referred to Supraregional PRU and Department of Immunology, Sheffield
Assay range notes
Results are expressed in terms of a grade or as a serum concentration of specific IgE
- Grade 0 = <0.35KUA/L (negative)
- Grade 1 = 0.35-0.7KUA/L (weak positive)
- Grade 2 = 0.7-3.5KUA/L (positive)
- Grade 3 = 3.5-17.5KUA/L (positive)
- Grade 4 = 17.5-52.5KUA/L (strong positive)
- Grade 5 = 52.5-100KUA/L (strong positive)
- Grade 6 = >100KUA/L (strong positive)Note Units are arbitarily related to total IgE international reference concentration)
Turnaround time
5 – 7 Days for in house testing, up to 28 days for referred testing.
Analysing laboratory
Immunology, The James Cook University Hospital