Published on January 31, 2022

COVID IgG (SARS CoV-2) Spike Antibody

Tube Type

Test ID LAB21125
CPT Code(s) 86769
Group/Individual Test Individual
Laboratory Clinical Immunology
Tube Station 30
Specimen Routine:

Serum: 3 ml blood/Serum Separator Tube/Gold Top

Plasma: 3 ml blood/EDTA (Purple Top) Tube

Availability Routine: Monday-Saturday
STAT: n/a
Turnaround Time 1-3 Days (Routine)
Reference Range Normal: Non-Reactive; See Important Comments.

Specimens submitted for detection of IgG antibodies to SARS-CoV-2 (COVID 19) spike antigen are tested using a chemiluminescent microparticle immunoassay (CMIA). The CMIA provides qualitative detection of SARS-CoV-2 IgG spike antibodies on the Diasorin Liaison instrument. Results are reported as positive or negative along with a value in Arbitrary Units (AU) per milliliter (AU/mL).

The Diasorin LIAISON SARS-CoV-2 IgG test has Emergency Use Authorization by the FDA as of April 26, 2020. The manufacturer’s performance specifications indicate a negative percent agreement of 99.5% based on analysis of 1899 pre-COVID-19 outbreak samples. Positive percent agreement (PPA) is 96.9%, based on testing of 32 subjects who tested positive by a SARS-CoV-2 PCR assay, varies by the time after disease onset. Samples should not be tested if collected from individuals less than 15 days post symptom onset.

This test detects IgG antibodies to a recombinant SARS-CoV-2 Trimeric spike protein.

Negative results do not rule out SARS-CoV-2 infection, particularly in those who have been in contact with the virus. Follow-up testing with a molecular diagnostic should be considered to rule out infection in these individuals.

Positive results do not rule out the potential for re-infection or indicate immunity to SARS-CoV-2 infection.

This test is not recommended for samples collected less than seven days after onset due to low sensitivity in the first week after onset.

Results from antibody testing should not be used as the sole basis to diagnose or exclude SARS-CoV-2 infection or to inform infection status.

Positive results may be due to past or present infection with non-SARS-CoV-2 coronavirus strains, such as coronavirus HKU1, NL63, OC43, or 229E.

This test detects antibodies induced by currently approved vaccines as well as by infection with SARS-CoV-2.

Fact Sheets for Patients and Providers contain further information on antibody testing for SARS-CoV-2

Reviewed by Christopher Parker on January 14, 2022

Note: Reference ranges provided on this web site are for guidance only, and may not reflect the most recent changes. Refer to laboratory reports for current reference data.

UNC Hospitals
McLendon Clinical Laboratories
101 Manning Drive
Chapel Hill, NC 27514