Data Show Common Allergy Tests Are Not Interchangeable

Thu May 8, 2008 12:27pm EDT

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- Results Vary Widely Compared to Established Clinical Standards Using
ImmunoCAP -

PORTAGE, Mich., May 8 /PRNewswire/ -- Data published in the May issue of
the Journal of Allergy and Clinical Immunology revealed variations in the
results of three common allergy diagnostic blood tests used to quantify
sensitivities to allergens.  The study, conducted by allergy specialists at
Mount Sinai School of Medicine, determined that the laboratory results from
two other commercial tests for specific IgE were not equivalent to those
measured by ImmunoCAP(R) Specific IgE blood test.
    Previously published studies from thought-leading allergists have
established threshold values for many food allergens.  These values are often
used to guide decisions about the severity of a patient's food allergy and
subsequent management strategies.  These published data are based upon values
determined using ImmunoCAP technology, which have become well-established.
    "Test results from the three different specific IgE assays are not
interchangeable.  This study underscores the importance of knowing which test
is being used to generate the patient's results, particularly with food
allergies, which can be life-threatening," said Robert Reinhardt, MD,
professor of family medicine for Michigan State University College of Human
Medicine and U.S. Medical Affairs Director, Phadia U.S. Inc.
    Specific IgE is produced in the blood as a result of sensitization to an
allergen and typically increases with exposure to that substance.  High
concentrations of food-specific IgE levels are predictive of a food-induced
allergic reaction.  These ImmunoCAP derived values provide a quantitative
assessment of allergen-specific IgE antibody, helping clinicians determine the
severity of an allergy and guide patient management strategies.
    The assays used in this study included ImmunoCAP, Turbo-MP (Agilent
Technologies offered by LabCorp (Laboratory Corporation of America)) and
3gAllergy Universal Module (Siemens' Immulite(R) system).  The tests measured
specific IgE levels in 50 patients for egg, milk, peanut, cat, birch and dust
mite.  The results revealed significant differences among the three tests in
the measurement of allergen-specific IgE levels, which can impact the clinical
decision-making process.
    When quantitative evaluation was performed, the Turbo-MP overestimated IgE
levels for egg but underestimated levels for dust mite and birch pollen.
Differences also were found between Turbo-MP and ImmunoCAP for milk, peanut
and cat.  The 3gAllergy Universal Module overestimated all allergen-specific
IgE levels compared with ImmunoCAP.
    "Results from these tests are used to guide treatment decisions, and
variability around the decision points can alter clinical management of a
suspected allergy," concluded the study authors.  "Food allergen avoidance on
the basis of inconsistent laboratory results can have profound nutritional and
social implications and can significantly affect a child and the child's
family's quality of life."
    Another study published in the Annals of Allergy, Asthma & Immunology in
July 2007 demonstrated that the ImmunoCAP Specific IgE system was directly
traceable to the World Health Organization (WHO) standard preparation for
total IgE in the detection of quantitative specific IgE antibodies.  This
traceability to the WHO standard was not equally demonstrated with the
Turbo-RAST and 3gAllergy Universal Module specific IgE assays.  The study was
the first of its kind to compare specific IgE results of different
technologies as measured against an independently verified IgE standard.
    "These studies further validate ImmunoCAP's overall performance as
compared to other specific IgE allergy blood tests, making it a valuable
option in the management of allergic disorders," said Michael Land, president
and general manager, Phadia U.S. Inc. "Physicians and patients need to be
aware that not all allergy blood tests are the same, and here is a study that
concludes that interchanging results can put children at unnecessary risk."
    Phadia AB, headquartered in Uppsala, Sweden, is the world leader in in
vitro IgE diagnostic research and product development.  Its U.S. affiliate is
in Portage, Michigan.  For more information, call Phadia Customer Service at
1-800-346-4364.
SOURCE  Phadia U.S. Inc

Nora Plunkett, +1-773-348-3800, ext. 204, for Phadia U.S. Inc
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