"ImmunoCAP® Rapid is the first point-of-care test to assist in the diagnosis of allergy in the physician’s office. Needing only a small sample of whole blood taken from the fingertip, the single-use, disposable device provides a first look at the IgE profile for patients based on the 10 most common inhaled allergens in the US.
With 2 minutes hands-on, the results are available in just 20 minutes, allowing the physician to quickly make evidence-based decisions." Click to view the test procedure (PDF) or click to watch the movie.
Two products are available:
- ImmunoCAP Rapid Wheeze/Rhinitis Child (PDF)
- ImmunoCAP Rapid Asthma/Rhinitis Adult (PDF)
It looks like Phadia is trying to position this device in direct competition with the skin prick test. ImmunoCAP Rapid is not the "first point-of-care test" - the skin prick test is.
The ImmunoCAP method was developed by Phadia. It utilizes a “sandwich” ELISA technique:
1. The ImmunoCAP sponge has allergen bound to it and serves as the first piece of bread ("bottom half").
2. Patient serum is added and specifc IgE to that allergen binds to the allergen on the sponge - this is the "meat" of the ELISA sandwich.
3. All of the unbound protein is washed away abd anti-IgE is added - this binds to the sIgE that was captured by the sponge in step two. The anti-IgE conjugate is the "second piece of bread" ("top half").
Allergen-specific IgE levels are not comparable between different laboratory methods - for example, ImmunoCAP vs. DPC Immulite 2000. Predictive values of specific IgE levels published in the literature for management of food allergies are based on studies using the ImmunoCAP assay. These predictive values cannot be applied to specific IgE levels from other assay systems.
Phadia Announces FDA Clearance of ImmunoCAP Rapid. Yahoo Finance.
Allergy blood testing: A practical guide for clinicians - CCJM review, 2011.
Image source: ImmunoCAP Rapid.