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Allergen Specific IgE In Vitro Testing | |
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Description: |
Allergen specific IgE in vitro testing is a procedure that measures allergen-specific immunoglobulin E (IgE) in human serum. The test is used to detect possible allergic responses to various substances in the environment such as animals, antibiotics, foods, grasses, house dust, mites, insects, trees, and weeds. It is also used in the evaluation of hay fever, extrinsic asthma, atopic eczema, and respiratory allergy. Since the allergy diagnosis is driven by a strong clinical history, this test is intended as an aid to diagnosis and the results are used in conjunction with medical history and physical examination.
There are several different methods of specific IgE in vitro testing. This policy describes and pertains to all methods of IgE in vitro allergy testing. The first method, the radioallergosorbent test (RAST) was commercially introduced in 1972 as the Phadebas RAST. Other versions of this test included the Phadezym RAST and the modified RAST. The RAST tests consisted of a 2-dimensional, allergen-coated paper disk and were qualitative tests, simply indicating if IgE was present or not. The ImmunoCAP is an in vitro IgE test that uses a 3-dimensional solid phase consisting of a flexible hydrophilic carrier polymer encased in a capsule. The ImmunoCAP is a fluorescent enzyme-linked immunoabsorbent assay which uses chemically induced fluorescence rather than radioactive labeling as did the older RAST tests. Other IgE in vitro tests that have become available include the Immulite 2000® system by Siemens and the Hy*Tec™ system by Hycor Biomedical Inc. The ImmunoCAP and the other immunoassays in use today are quantitative tests, providing a level indicating the amount of serum IgE present for each specific allergen.
The allergen-specific IgE is most valuable when direct skin testing is contraindicated.
Skin testing is preferred over in-vitro methods such as RAST because it detects the presence of IgE antibody in tissue and shows biologic activity. Since IgE-mediated allergy is caused by IgE antibodies bound to mast cells (not IgE antibodies in circulation), in-vitro tests generally are less sensitive than skin tests for diagnostic use. In-vitro tests can give false-positive results in patients with high total serum IgE and false negative results in patients treated with immunotherapy who have significant allergen-specific IgG antibodies.
According to the American Academy of Allergy and Immunology, skin testing is more economical per test than in-vitro IgE tests, and therefore, properly performed skin testing is generally the method of testing. Selective use of in-vitro tests can be justified in patients with extensive dermatopathic conditions, in patients who cannot be withdrawn from medications that interfere with proper skin testing, and occasionally, in instances where a patient refuses skin testing.
The American Academy of Allergy and Immunology has concluded that in vitro IgE testing is a valid method for detection of allergen specific IgE antibody in serum, as reported in their position statements published in the Journal of Allergy and Immunology.
When these tests are performed and appropriately interpreted in combination with a clinical history and physical examination, obtained personally by a physician properly trained in the diagnosis and treatment of allergic and immunologic diseases, in-vitro IgE tests can provide a satisfactory alternative to skin testing for confirmation of the diagnosis of most patients with clinically significant aeroallergen disease and IgE dependent food allergy.
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Policy/ Coverage: |
Effective April 2016
Meets Primary Coverage Criteria Or Is Covered For Contracts Without Primary Coverage Criteria
Up to 25 screening allergen specific in vitro IgE tests meet primary coverage criteria for effectiveness and are covered only for the evaluation of 1) rhinitis (not related to foods or preservatives), 2) extrinsic asthma, 3) extrinsic allergic alveolitis, 4) pulmonary eosinophilia, 5) atopic dermatitis, 6) urticaria or 7) anaphylactic shock due to adverse food reactions, venom or serum. Even then, they are covered only when certain conditions prevent the performance, or adversely affect the interpretation, of skin tests.
Those conditions are:
Medical record documentation must state which of the above conditions precludes skin testing.
If the above conditions are present, up to 25 screening allergen specific in vitro IgE tests will be covered. If one or more of these is unequivocally positive, up to 15 additional tests may be covered. A maximum number of 40 tests will be allowed. A copy of the positive screening allergen specific in vitro IgE test is the only documentation needed with the claim for coverage of the additional 15 tests.
Does Not Meet Primary Coverage Criteria Or Is Investigational For Contracts Without Primary Coverage Criteria
Allergen specific in vitro IgG testing does not meet member benefit certificate primary coverage criteria and is not covered.
For members with contracts without primary coverage criteria, allergen specific in vitro IgG testing is considered not medically necessary. Services that are considered not medically necessary are specific contract exclusions in most member benefit certificates of coverage.
Effective April 2011 to March 2016
Up to 10 screening allergen specific in vitro IgE tests meet primary coverage criteria for effectiveness and are covered only for the evaluation of 1) rhinitis (not related to foods or preservatives), 2) extrinsic asthma, 3) extrinsic allergic alveolitis, 4) pulmonary eosinophilia, 5) atopic dermatitis, 6) urticaria or 7) anaphylactic shock due to adverse food reactions, venom or serum. Even then, they are covered only when certain conditions prevent the performance, or adversely affect the interpretation, of skin tests.
Those conditions are:
Medical record documentation must state which of the above conditions precludes skin testing.
If the above conditions are present, up to 10 screening allergen specific in vitro IgE tests will be covered. If one or more of these is unequivocally positive, up to 30 more tests may be covered. A copy of the positive screening allergen specific in vitro IgE test is the only documentation needed with the claim for coverage of the additional 30 tests.
Effective, Prior to April 2011
Up to ten screening RAST tests meet primary coverage criteria for effectiveness and are covered only for the evaluation of rhinitis, extrinsic asthma, extrinsic allergic alveolitis, pulmonary eosinophilia, atopic dermatitis, urticaria, anaphylactic shock due to adverse food reactions, venom or serum. Even then, they are covered only when certain conditions prevent the performance, or adversely affect the interpretation, of skin tests. Those conditions are:
Medical record documentation must state which of the above conditions precludes skin testing.
If the above conditions are present, up to 10 screening RAST tests will be covered. If one or more of these is unequivocally positive, up to 30 more RAST tests may be covered. A copy of the positive screening RAST test is the only documentation needed with the claim for coverage of the additional 30 RAST tests.
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Rationale: |
2010 Update
A review of the literature has been conducted through August 2010. There was no new literature identified that would prompt a change in the coverage statement.
2011 Update
A literature search was conducted through March 2011 on allergen specific in vitro IgE testing.
The American College of Allergy, Asthma and Immunology (ACAAI) together with the American Academy of Allergy, Asthma and Immunology (AAAAI) published a Joint Task Force Report on allergy diagnostic testing (Cox, 2008). This report discusses in vitro versus in vivo allergy testing. The report indicates that although both in vivo (skin) and in vitro (laboratory) testing can be used to confirm the presence of allergen s-IgE antibodies, skin testing is still the preferred test to confirm an allergic response because it is minimally invasive, has good reproducibility and results can be available within 15 minutes. In vitro testing would be the preferred choice when skin testing is not indicated; in patients with severe skin diseases, uncooperative patients, patients receiving medications that would interfere with skin testing and patients with a risk of anaphylaxis from the testing.
The report also addresses the important issue regarding what allergens should be tested. The patient’s history and known exposures are essential to narrowing the list of tests to order. “The selection of allergens for testing should not be ordered randomly but instead be based on symptoms, environmental and occupational exposures, age and other relevant factors, and all allergy test results need to be interpreted in the context of the clinical history”. The Allergy Diagnostic Practice Parameter, updated in 2008 states, “Routine use of large numbers of skin tests or routine annual tests without a definite clinical indication are clearly not justified” (Bernstein, 2008).
The information in the most recently updated report from the ACAAI/AAAAI Joint Task Force supports the existing coverage statements.
2012 Update
A search of the MEDLINE database through September 2012 did not reveal any new information that would prompt a change in the coverage statement.
2014 Update
A literature search conducted through September 2014 did not reveal any new information that would prompt a change in the coverage statement.
2017 Update
A literature search conducted using the MEDLINE database through October 2017 did not reveal any new information that would prompt a change in the coverage statement.
2018 Update
A literature search was conducted through November 2018. There was no new information identified that would prompt a change in the coverage statement.
2021 Update
Annual policy review completed with a literature search using the MEDLINE database through November 2021. No new literature was identified that would prompt a change in the coverage statement.
2022 Update
Annual policy review completed with a literature search using the MEDLINE database through November 2022. No new literature was identified that would prompt a change in the coverage statement.
2023 Update
Annual policy review completed with a literature search using the MEDLINE database through November 2023. No new literature was identified that would prompt a change in the coverage statement.
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CPT/HCPCS: | |
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References: |
Am Academy of Allergy, Asthma and Immunology. Position statement: the use of in vitro tests for IgE antibody in the specific diagnosis of IgE-mediated disorders and in the formulation of allergen immunotherapy. J Allergy Clin Immuno 1992; 90:263-267. Bernstein IL, Li JT, Bernstein DI, et al.(2008) American Academy of Allergy, Asthma and Immunology, American College of Allergy, Asthma and Immunology. Allergy diagnostic testing: an updated practice parameter. Part 1. Ann Allergy Asthma Immunol 2008 Mar;100(3 Suppl 3):S15-S66. Bernstein IL, Li JT, Bernstein DI, et al.(2008) American Academy of Allergy, Asthma and Immunology, American College of Allergy, Asthma and Immunology. Allergy diagnostic testing: an updated practice parameter. Part 2. Ann Allergy Asthma Immunol 2008 Mar;100(3 Suppl 3):S66-S121. Cox L, Williams B, Sicherer S, et al.(2008) Pearls and pitfalls of allergy diagnostici testing: report from the American College of Allergy, Asthma and Immunology/American Academy of Allergy, Asthma and Immunology Specific IgE Test Task Force. Ann Allergy Asthma Immunol. 2008;101:580-592. Crockard AD, Ennis M.(2001) Basophil histamine release tests in the diagnosis of allergy and asthma. Clin Exp Allergy 2001; 31(3):345-50. Lawlor GJ, et al.(1995) Allergy and immunology. Manual Allergy and Immunology 1995. Paris-Kohler A, Demoly P, Persi L, et al.(2000) In vitro diagnosis of cypress pollen allergy by using cytofluorimetric analysis of basophils (Bastotest). J Allergy Clin Immunol 2000; 105(2 pt 1):339-45. Serial Endpoint Testing for the Diagnosis and Treatment of Allergic Reactions. 2002 Blue Cross Blue Shield Association Technology Evaluation Center Assessment. Tierney L, McPhee S, Papadakis M.(1996) Allergic and immunologic disorders. Curr Med Diagnosis and Treatment 1996; 98-99; 712-715. |
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Group specific policy will supersede this policy when applicable. This policy does not apply to the Wal-Mart Associates Group Health Plan participants or to the Tyson Group Health Plan participants.
CPT Codes Copyright © 2024 American Medical Association. |