What is Anti dsDNA - (ELISA)?

Also Known As: Antibody to ds-DNA Native double-stranded DNA Antibody anti-DNA Double-stranded DNA Antibody

Formal Name: anti-double-stranded DNA, IgG

Anti-double stranded DNA antibody (anti-dsDNA) is one of a group of autoantibodies called antinuclear antibodies (ANA). Normally, antibodies protect against infection, but autoantibodies are produced when a person’s immune system fails to adequately distinguish between “self” and “non-self.” They mistakenly attack the body’s own healthy cells, causing tissue and organ damage. Anti-dsDNA specifically targets the genetic material (DNA) found in the nucleus of a cell, hence the name “anti-dsDNA.” The anti-dsDNA test identifies the presence of these autoantibodies in the blood.

While anti-dsDNA may be present at a low level with a number of disorders, it is primarily associated with lupus. Lupus is a chronic inflammatory autoimmune disorder that can affect various tissues and/or organs of the body such as the kidneys, joints, blood vessels, skin, heart, lungs, and brain. (For more on this, read the article on Lupus). The test for anti-dsDNA, along with other autoantibody tests, may be used to help establish a diagnosis of lupus and distinguish it from other autoimmune disorders.

One serious complication of lupus is lupus nephritis, a condition characterized by inflammation of the kidneys, which can lead to protein in the urine, high blood pressure, and kidney failure. It occurs when autoantibodies bind to antigens that have been deposited in the kidneys. In the evaluation of someone with lupus nephritis, a high level (titer) of anti-dsDNA is generally associated with ongoing inflammation and damage to the kidneys.

Why Get Tested?

To help diagnose and monitor lupus (systemic lupus erythematosus, SLE)

When To Get Tested?

When you have a positive ANA test and signs and symptoms associated with lupus, such as persistent fatigue, pain in your joints and a red rash resembling a butterfly across the nose and cheeks; periodically used to assess disease activity in those who have been diagnosed with lupus

Sample Required?

A blood sample drawn from a vein in your arm

Test Preparation Needed?

None

How is the test used?

The anti-double-stranded DNA (anti-dsDNA) test is used to help diagnose lupus (systemic lupus erythematosus, SLE) in a person who has a positive result on a test for antinuclear antibody (ANA) and has clinical signs and symptoms that suggest lupus.

Typically, an ANA test is the first test performed to evaluate an individual for an autoimmune disorder. While a positive ANA test is seen in about 95% of lupus cases, it may be seen in many other conditions as well. The anti-dsDNA test is fairly specific for lupus; however, only 65-85% of people with lupus may be positive; that is, a negative anti-dsDNA does not rule out lupus. If a person has a positive ANA, an anti-dsDNA test may be used to distinguish lupus from other autoimmune disorders that have similar signs and symptoms.

An anti-dsDNA test may be ordered along with a test for anti-Sm (Smith antibody), another antinuclear autoantibody associated with lupus, to help establish a diagnosis. The anti-Sm test may be ordered as part of an extractable nuclear antigen (ENA) panel. Depending upon clinical signs and the healthcare practitioner’s suspicions, other autoantibodies may also be ordered to help distinguish between, and rule out other autoimmune disorders. Examples include tests for histone antibody (drug-induced lupus) and antiphospholipid antibodies.

The anti-dsDNA test may be used to assess disease activity in a person who has been diagnosed with lupus. Those with lupus often have flare-ups in which symptoms worsen and then subside. An increased anti-dsDNA level may be seen prior to and during these flare-ups. In particular, this test may be used to monitor lupus nephritis, a serious complication of lupus that can cause kidney damage and inflammation. This can lead to protein in the urine, high blood pressure, and kidney failure. It occurs when the autoantibodies bind to antigens that have been deposited in the kidneys.