Anti-DNA Test – Diagnostic Tool for SLE

Anti-DNA Test – Diagnostic Tool for Systemic Lupus Erythematosus (SLE)

Anti-DNA Test

Synonyms: Antibody to Double-Stranded DNA, Anti-ds-DNA, DNA Antibody, n-DNA, ss-DNA, Antibody to Native DNA

Test Commonly Includes

Titers are reported on specimens that test positive.

Specimen

Type: Serum

Container: Red top tube

Storage Instructions

Refrigerate immediately if not processed promptly.

Reference Range

Low or undetectable antibody levels are considered normal. Reference ranges may vary based on the testing laboratory and methodology.

Use

This test is primarily used to confirm systemic lupus erythematosus (SLE) and to monitor disease progression and therapeutic response.

Methodology

• Indirect Fluorescent Antibody (IFA) using Crithidia luciliae
• Radioimmunoassay (RIA)
• Enzyme Immunoassay (EIA)

Additional Information

• Anti-ds-DNA antibodies are present in 80–90% of SLE cases and correlate well with disease activity, especially lupus nephritis.
• May also be found in:
  • Other rheumatic diseases
  • Chronic active hepatitis
  • Infectious mononucleosis
  • Primary biliary cirrhosis
• Presence of anti-ss-DNA and other extractable nuclear antigens (ENA) in ANA-negative lupus has been documented.
• Crithidia luciliae substrate may yield false positives due to anti-histone antibodies.
• Titers can be used to monitor treatment but should not be the sole basis for therapy decisions.
• Drugs like procainamide and hydralazine can induce anti-ss-DNA and anti-histone antibodies.

Limitations

Anti-ds-DNA alone is not sufficient or necessary for a definitive diagnosis of SLE. Test interpretation should always consider clinical context and other immunologic markers.

References

• Carson DA. “The Specificity of Anti-DNA Antibodies in Systemic Lupus Erythematosus.” J Immunol, 1991; 146(1):1-2.
• Christian CL. “Prognostic and Therapeutic Implications of Immunologic Test Results in Rheumatic Disease.” Hum Pathol, 1983; 14:446-8.
• Colvin RB, Bhan AK, McCluskey RT, eds. Diagnostic Immunopathology, Raven Press, 1988.
• Harmon CE. “Antinuclear Antibodies in Autoimmune Disease.” Med Clin North Am, 1985; 69:547-63.
• James K, Meek G. “Evaluation of Commercial Enzyme Immunoassays…” Am J Clin Pathol, 1992; 97(4):559-65.
• Suenaga R, Evans M, Abdou NI. “Idiotypic and Immunochemical Differences…” Clin Immunol Immunopathol, 1991; 61(3):320-1.
• Jacobs, Demott, Finley, et al. Laboratory Test Handbook, Lexi-Comp Inc, 1994.