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Lab Dept:
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Serology
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Test Name:
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VZV IgG ANTIBODY
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General Information
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Lab Order Codes:
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VZG
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Synonyms:
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Anti-VZV Antibodies-IgG ; VZV IgG Serology; Varicella Zoster IgG Antibody
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CPT Codes:
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86787 – Antibody, varicella zoster (IgG)
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Test Includes:
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Anti-VZV Antibodies, IgG
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Logistics
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Test Indications:
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Intended for the qualitative detection of IgG antibodies to Varicella Zoster Virus in human sera to indicate the following: no exposure to VZV or previous infection with VZV.
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Lab Testing Sections:
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Chemistry (Performed on the St. Paul campus)
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Phone Numbers:
Minneapolis:
Saint Paul:
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612-813-6280
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651-220-6550
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Test Availability:
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Daily, 24 hours
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Turnaround Time:
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1 - 3 days, testing is performed daily, Mon – Fri, during normal business hours
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Special Instructions:
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N/A
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Specimen
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Specimen Type:
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Blood
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Container:
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Red top tube, plain, no gel
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Draw Volume:
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1 mL blood
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Processed Volume:
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0.25 mL serum
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Collection:
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Blood should be collected aseptically by venipuncture and placed in a plain, red top tube or other plain sterile tube without anticoagulant and allowed to clot at room temperature.
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Special Processing:
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Lab Staff: Centrifuge specimen as early as possible after clotting; transfer serum to a plain polypropylene tube and refrigerate. If testing is delayed longer than 48 hours, serum should be frozen at -20ºC or colder. Do not store serum in a self-defrosting freezer.
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Patient Preparation:
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None
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Sample Rejection:
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Sera exhibiting a high degree of hemolysis, icterus, lipemia or microbial contamination are not recommended because these conditions may cause aberrant results; mislabeled or unlabeled specimens
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Interpretive
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Reference Range:
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The results will be reported as a numerical value with interpretation.
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<135
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Negative
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>165
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Positive
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135 - 165
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Equivocal
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Interpretation:
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IgG Result
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Interpretation
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Negative
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Patient not exposed or too early
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Positive
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Immunity from past exposure, not acute disease
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Equivocal Result: “Borderline result” – suggest repeat specimen be obtained in 7-14 days.
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Critical Values:
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N/A
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Limitations:
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Samples collected early in the course of a VZV infection may not have detectable levels of antibody. In such cases, it is recommended that a second serum sample be obtained 2-3 weeks later.
Positive results on VZV-IgG antibody in neonates should be interpreted with caution, since maternal IgG is transferred passively from mother to baby before birth. IgM assays are generally more useful indicators of infection in children below the age of 6 months.
Performance characteristics with individuals vaccinated with VZV (ROD strain) have not been established.
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Methodology:
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Chemiluminescent Immunoassay (CLIA)
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References:
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Liaison® VZV IgG (January 2009) Directions for Use, DiaSorin, Inc., Stillwater, MN 55082
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NCCLS Guideline I/LA 18-A2 (September 2001) Specifications for Immunological Testing for Infectious Diseases, Approved Guideline – Second Edition, Vol 21, No 15
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Updates:
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2/1/2006: Test previously included both IgM and IgG testing. IgM testing is now orderable separately.
8/29/2011: Testing method change, previously listed as ELISA. Note updated reference ranges.
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