Double-Stranded DNA (dsDNA) Antibody, IgG by ELISA with Reflex to dsDNA Antibody, IgG by IFA
Also known as: DNA
Use
Positivity for anti-double stranded DNA (anti-dsDNA) IgG antibody is a diagnostic criterion of systemic lupus erythematosus (SLE). This test is used as a secondary screening for SLE based on ANA results. The test initially screens specimens by enzyme-linked immunosorbent assay (ELISA) and reflexes positive results to a specific indirect fluorescent antibody (IFA) titer, aiding in the diagnosis of SLE. Some patients with early or inactive SLE may test positive by ELISA but negative by IFA, suggesting a further ANA test by IFA in cases of strong clinical suspicion.
Special Instructions
The test is reflexive, meaning that positive ELISA results (>24 IU) will be reflexed to a highly specific IFA titer for confirmation, which might incur additional charges. If the patient is negative by CLIFT but positive by ELISA and clinical suspicion remains, consider antinuclear antibody (ANA) testing by IFA.
Limitations
The IFA test is highly specific for systemic lupus erythematosus (SLE) but may not detect anti-dsDNA antibodies in all patients with SLE, especially in early or inactive phases. Patients may test positive in ELISA but negative in IFA; such results may necessitate additional testing, like ANA by IFA, depending on clinical suspicion.
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 58465-6
Result Turnaround Time
1-3 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.5 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Separate serum from cells as soon as possible or within 2 hours of collection.
Storage Instructions
Refrigerated.
Causes for Rejection
Plasma. Contaminated, hemolyzed, or severely lipemic specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |
| Refrigerated | 2 weeks |
| Frozen | 1 month (avoid repeated freeze/thaw cycles) |
