This site is intended for healthcare professionals

Go to /sign-in page

You can view 5 more pages before signing in

Anti-double stranded DNA

Last reviewed dd mmm yyyy. Last edited dd mmm yyyy

Authoring team

This autoantibody is associated with systemic lupus erythematosus (SLE) in which it is found in 50% of cases. Though less sensitive it is a more specific test than antinuclear factor, since it is seldom positive in other conditions (1).

It is associated with more severe disease, vasculitis and nephritis in SLE. The HLA-markers associated with SLE and anti-dsDNA are HLA-DR2 and HLA-DQB1.

Antiantibodies to double-stranded DNA (dsDNA) have also been reported as a consequence of medications such as minocycline and tumour necrosis factor-alpha inhibitors - thus their significance should be made in the context of the full clinical picture (2).

Laboratories may mention the Crithidia luciliae test (see notes for details)

  • this haemoflagellate has giant mitochondria containing dsDNA (but not single-stranded DNA (ssDNA) - this lends itself to detection of dsDNA antibodies by immunofluorescence

Autoantibodies to ssDNA

  • found in many connective tissue disorders and other conditions - are of little diagnostic use due to their lack of specificity (2)

Notes:

  • dsDNA antibodies are excellent indicators of SLE disease activity and their elevated levels usually precede exacerbation of disease (sometimes by more than a year) (3)
    • anti-dsDNA levels rise during flares of SLE disease activity, especially in lupus nephritis (3)
  • laboratory methods for detecting anti-dsDNA
    • anti-dsDNA antibodies are generally detected and quantified by commercially available kits for enzyme-linked immunosorbant assay (ELISA, also automated versions), Crithidia luciliae immunofluorescence assay (CLIFT), and radioimmunoassay methods developed according to Farr technique
      • different combinations of these methods are used in diagnostic laboratories worldwide, without a consensus on exclusive methods
      • an important cause of discrepancies between results obtained with different methods lies in the avidity of antibodies
        • ELISAs detect antibodies of both low and high avidity, whereas CLIFT and FARR-RIA assays predominantly detect antibodies of high avidity
    • for the diagnosis of SLE, it is crucial that the anti-dsDNA assay is highly specific for dsDNA, especially since elevated levels of anti-dsDNA antibodies can also be detected in other autoimmune diseases, as well as in blood donors, very much depending on the detection method used
      • FARR-RIA has the highest specificity for anti-dsDNA antibodies detection but a low sensitivity (3)
      • CLIFT detects both high and low avidity anti-dsDNA antibodies and may be used as a primary screen (3)
        • retesting of positive samples with FARR-RIA not only confirms the diagnosis but also provides the quantitative data allowing the monitoring of disease activity
      • problem with anti-dsDNA ELISAs is that they often give false-positive results due to binding of immune complexes (with negatively charged moieties) to the pre-coat intermediates
      • antibodies against single-stranded DNA only recognize single-stranded DNA and are specifically directed against purine and pyrimidine bases
        • observed not only in patients with SLE but also in other connective tissue diseases, such as systemic sclerosis and myositis

Reference:

 


Related pages

Create an account to add page annotations

Annotations allow you to add information to this page that would be handy to have on hand during a consultation. E.g. a website or number. This information will always show when you visit this page.