Allergy: Specific IgE antibodies
Also known as: RAST; Allergen Testing; SIgE
Specific IgE tests are available to a wide range of antigens. However, the Gold Standard is a thorough clinical history along with skin prick tests except in the following cases:
- Small children
- Those with extensive skin involvement that precludes skin testing
- Where there is a risk of anaphylaxis
In the absence of a strong clinical history, Specific IgE analysis is of little significance.
Blanket requests for 'RAST testing' will be ignored.
Please give full details of suspected allergens and symptoms. Tests for specific IgE to penicillin are not reliable in diagnosing immediate type hypersensitivity to this drug.
For further information on Food Allergy in children and young people, please see the latest NICE Clinical Guideline (CG116).
View a list of available antigens
Specimen requirements
Serum 2ml
Cost
Price on application
Laboratory turnaround time
5 days
Laboratory method
Immunocap automated Enzyme Immunoassay
Reference range/units
Reported as Grades |
Units (Ku/l) |
Interpretation |
0 |
0 - 0.35 |
Negative |
1 |
0.35 - 0.7 |
Weakly positive |
2 |
0.7 - 3.5 |
|
3 |
3.5 - 17.5 |
|
4 |
17.5 - 50 |
|
5 |
50 - 100 |
|
6 |
>100 |
Strongly positive |
Associated tests
Not applicable
Sample stability
2 months at 2-8ºC
Shipping and storage
UK and Ireland
Ambient temperature and first class post. Hays DX users please enquire via email below.
International
Ambient temperature if courier will deliver within 72 hours otherwise consider refrigerated transport. Freezing is not a requirement.
Ensure delivery Monday to Friday 09:00 - 17:30.
Further information and contact details
For further information, email immunologylab.enquiries@ouh.nhs.uk
Last reviewed:06 October 2023