ImmunoCAP™
Specific IgE Blood Test
Overview
Diagnostic
Value

The ImmunoCAP Specific IgE blood test was cleared by the FDA in 2001
as the first and then only test for quantitative measurement of specific IgE.

In clinical tests, ImmunoCAP technology has been demonstrated to be
close to an ideal lab determination to identify specific IgE with high
sensitivity and specificity.

ImmunoCAP can quantitatively and accurately determine if patients are
allergic and exactly what they are allergic to.

Over lapping symptoms of allergic-like disease create the need for an
evidence based diagnosis. Additionally, regional (ICSI), national (NIH),
and international (ARIA) guidelines all have a diagnostic testing
component.

Testing should be done on children with 1) chronic eczema (atopic
dermatitis), 2) chronic GI disturbance, 3) chronic rhinitis, 4) chronic
recurring otitis media, and 6) asthma; and adults with 1) chronic
rhinitis/sinusitis or 2) asthma.
Patients may have Respiratory Disease, upper and lower, associated with rhinitis,
sinusitis, and allergic rhinitis. The source of their symptoms may be viral, bacterial,
or allergic, making definitive diagnosis an essential step in determining treatment.
Allergy is often referred to as a threshold disease, meaning that individuals can be
allergic to one or more things, but may not exhibit symptoms until they are
exposed to enough allergic triggers to put them “over the top.” Sometimes
treatment is as simple as taking an allergic trigger out of a patient’s environment.
ImmunoCAP provides quantitative evidence that clearly demonstrates the
appropriateness and value of a patient’s treatment plan. The right treatment
decisions, based on clinical evidence, mean appropriate use of antibiotics,
antihistamines, and intranasal steroids, fewer repeat office visits, and fewer
unnecessary referrals.
Principle of
Assay
The unique technology of ImmunoCAP provides high binding capacity of clinically
relevant allergen proteins, including those present in very low levels. It measures
specific IgE unique to the respective allergen bound to the ImmunoCAP solid
phase.
The ImmunoCAP consists of a reaction chamber containing a cellulose sponge
matrix, which is a flexible hydrophilic polymer to which allergenic components are
covalently coupled. This three-dimensional solid phase has a high binding capacity
and is an excellent carrier of allergens.
The design of the solid phase is crucial to the performance characteristics of an
assay, because of the complexity of allergen source materials and the diversity of
individual IgE antibody specificities. To provide quantitative results and high
sensitivity, it is critical that the capacity of the solid phase is high enough to bind all
clinically relevant proteins of the allergen.
ImmunoCAP binds almost 150 times more protein than a passively coated tube,
and at least 3 times more protein than a paper disc.
Clinical
Interpretation
The test can be run on patients of any age and regardless of skin condition. There
is no need to stop current medications prior to drawing a blood sample.
Two important requirements for a quantitative test for specific IgE antibodies are 1)
the ability to report results in internationally standardized units, and 2) the
demonstration of parallelism between calibrator and sample dilutions. ImmunoCAP
total IgE concentrations are expressed as a concentration of International Units
IgE (kU/L) and the calibrators are directly traceable to the WHO International
Reference Preparation for human IgE 75/502.
With consumer awareness at an all-time high, it is important to provide an
evidence-based diagnosis and treatment regimen. ImmunoCAP profile can with
95% certainty rule in or rule out atopic disease as the cause of or contributing
factor to allergy like symptoms associated with upper and lower respiratory
disease.
Specimen
Requirements
Allergens may be ordered individually or as a Profile.
0.5 mL serum for first allergen with 0.2 mL serum required for each additional
allergen. Refrigerate.
To order SVCL Respiratory Disease Profile:
(Includes 16 individual allergens and Total IgE)
SVCL Test Code 3085
Submit 4 mL serum (3.0 mL minimum.). Refrigerate.
CPT Codes: 86003 (16); 82785
References
ImmunoCAP Specific IgE Blood Test Brochure, Pharmacia Diagnostics, 99044.03
ImmunoCAP Specific IgE Blood Test, Available at:
http://www.questdiagnostics.com/hcp/topics/immunocap/immunocap.html. Accessed: June 16, 2005