House Dust Allergen-Specific IgE Antibody, Serum — Radioallergosorbent (RAST), Qualitative
A blood test that looks for IgE antibodies to house dust allergens, including common dust mite proteins, to help evaluate suspected allergic sensitization.
["A positive result suggests an allergy-related immune response to house dust or dust mite allergens."]
Key facts at a glance
- LOINC
- 21344-7
- Short code
- Deprecated House Dust Greer IgG RAST Ql
- Synonyms
- Deprecated House Dust Greer IgG RAST Ql
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84484
- SNOMED
- 302774002
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
This test measures allergen-specific IgE antibodies in the blood that react with house dust allergens, such as proteins from common dust mites. It is sometimes called a radioallergosorbent test, or RAST.
Why might I need this test?
Your clinician may order it when you have sneezing, congestion, wheezing, or eye symptoms that seem related to dust or dust mites. It can help identify whether these allergens trigger an immune response.
How is the test performed?
A blood sample is collected and the serum is tested in the laboratory for antibodies against house dust allergens. Unlike a skin-prick test, this test does not require the allergen to be placed under your skin.
How do I prepare for the test?
Fasting is usually not required. Tell your clinician about any allergy medicines or immune treatments you use, and follow their instructions if they advise changing or holding a medication before testing.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A positive result indicates that your immune system has produced IgE antibodies to a house dust or dust mite allergen. This supports allergic sensitization but should be interpreted with your symptoms, exposure history, and other allergy evaluation findings. A negative result does not completely rule out an allergy because some relevant allergens may not be represented in the test.
Short name
House dust-specific IgE (RAST)
Frequently asked questions
Does a positive result mean I am allergic to house dust?
Is this the same as a dust mite skin-prick test?
Can I use the result to choose allergy treatment?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy