Anti-dsDNA (Double-stranded) Ab by Farr method (RDL)

Casandra

Casandra Test Code LC69707Version 1 (DRAFT)

Performing Lab

Lab LabcorpLab Test ID 520059CPT Code 86225

Anti-dsDNA (Double-stranded) Ab by Farr method (RDL)

Also known as: Double Stranded DNA by Farr, dsDNA, DsDNA Farr, Farr, Lupus

Clinical Use

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Use

The Farr method detects the high avidity anti-dsDNA antibodies. The Farr assay is the most specific method for detecting dsDNA auto antibodies. Significant elevations in dsDNA autoantibody concentrations confirm the diagnosis of systemic lupus erythematosus (SLE). Serial studies of elevated values of dsDNA auto antibodies are useful for predicting activity of SLE and for measurement of serum C3 or C4 concentrations. Absence of dsDNA autoantibodies does not exclude the diagnosis of SLE. Doubling of dsDNA autoantibody concentrations or increases greater than 30 IU/mL in less than 10 weeks are reliably predictive of exacerbations of SLE. A simultaneous decrease in serum C4 complement enhances this predictive value.

Special Instructions

To avoid delays in turnaround time when requesting multiple tests on frozen samples, submit separate frozen specimens for each test requested.

Limitations

This test was developed and its performance characteristics were determined by LabCorp. It has not been cleared or approved by the Food and Drug Administration, which could impact its availability in regulated environments or affect insurance coverage. Interference can occur in lipemic, hemolyzed, or contaminated samples, which may lead to inaccurate results.

Test Details