SARS CoV-2 Spike Antibody, Semi-Quant, Serum

Label Mnemonic:	COVSQ
Epic code:	LAB9601
Order form:	Laboratory Requisition
Supply order:	Supply Order Form
Billing:	Billing Policies
CPT code:	86769

Specimen(s):

Plasma

Collection Medium:

BD Gold SST 5 mL Vacutainer

Minimum:

1.5 mL serum

Testing Schedule:

Monday, Wednesday, Friday

Turn Around Time:

1–4 days upon receipt at performing laboratory

Reference Range:

Negative

Interpretive Data:

This assay provides qualitative and semi-quantitative results for the presence of antibodies to the receptor binding domain on the SARS-CoV-2 spike glycoprotein. Both vaccine and recent infection can stimulate antibodies against this domain.

Negative:

No antibodies to SARS-CoV-2 spike glycoprotein detected. Negative results may occur in serum collected too soon following infection or vaccination, in immunosuppressed patients, or in patients with mild or asymptomatic infection. This test does not rule out active or recent COVID-19 infection. Follow-up testing with a molecular test for SARS-CoV-2 is recommended in symptomatic patients.

Positive:

Antibodies to the SARS-CoV-2 spike glycoprotein detected. Results suggest recent or prior SARS-CoV-2 infection or vaccination. Serologic results should not be used to diagnose recent SARS-CoV-2 infection as antibodies remain detectable for months to years after infection/vaccination.

For the manufacture of COVID-19 convalescent plasma using the Roche Diagnostics anti-SARS-CoV-2 spike electro-chemiluminescence immunoassays, per current US Food and Drug Administration Emergency Use Authorization guidelines, high-titer convalescent plasma is defined as plasma units with a semi-quantitative value of 132 U/mL and above (see appendix A: www.fda.gov/media/141477/download).

Test Limitations:

Negative results do not preclude SARS-CoV-2 infections. If an acute infection is suspected, direct testing for SARS-CoV-2 virus is necessary.

False-positive results for Roche Anti-SARS-CoV-2 IgG test may occur due to cross-reactivity from pre-existing antibodies or other possible causes.

In rare cases, interference due to extremely high titers of antibodies to analyte-specific antibodies, streptavidin, or ruthenium can occur.

Serum biotin concentrations up to 1200 ng/mL do not interfere with this assay. Extremely high concentrations of biotin in patient serum due to heavy administration or supplementation of biotin may falsely depress Anti-SARS-CoV-2 antibody detection.

In rare cases, some individuals can develop antibodies to mouse or other animal antibodies (often referred to as human antimouse antibodies [HAMA] or heterophile antibodies), which may cause interference in some immunoassays. The presence of antibodies to streptavidin or ruthenium rarely occur and may also interfere with this assay. Caution should be used in interpretation of results, and the laboratory should be alerted if the result does not correlate with the clinical presentation.

Methodology:

Electrochemiluminescence immunoassay

Sample Processing:

Centrifuge at a speed and time necessary to get barrier separation of plasma/serum and cells within 1 hour of collection. Send specimen in original tube. Do Not transfer to another tube.
Each sample must be labeled with at least TWO full patient identifiers (First/Last Name & DOB are sufficient for non-UIHC affiliated clients) to avoid sample rejection/delays.

Sample Storage:

Refrigerate.
All sample storage requirements are intended for delivery to UIHC within 24 hours of collection for testing. If samples won't arrive in this time period, please call the UIHC Core Lab for alternative storage/shipping instructions (319-356-3527).

Transport Instructions:

Place labeled specimen into zip-lock type biohazard bag; seal bag.
Place completed requisition into outside pocket of bag.
Transport in cooler with refrigerated coolant packs.