DNA (ds) Antibody, Crithidia IFA with Reflex to Titer Test
This test measures antibodies to double-stranded DNA, or dsDNA, in a blood sample using an immunofluorescence method called the Crithidia luciliae substrate assay. If the initial screen is positive, Quest reflexes the sample to a titer for further detail.
About this test
The test measures dsDNA antibodies in serum using immunofluorescence assay methodology. Quest describes these antibodies as detected in patients with active systemic lupus erythematosus (SLE) and in some patients with mixed connective tissue disease, which is part of why the test is used in evaluating autoimmune activity.
Quest lists preparation for this test: an overnight fast before the blood draw is preferred when possible. If the DNA (ds) antibody screen comes back positive, the reflex step runs a DNA (ds) antibody titer on the same sample to give a more detailed read.
Who might consider this test?
- A single result is read by a clinician alongside symptoms and other findings rather than as a stand-alone answer.
Test details
| Collection | Quest patient service center |
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Quest resources
Additional details
What this test looks at
The test reports whether dsDNA antibodies are present in a serum sample, using the Crithidia luciliae immunofluorescence substrate assay. A positive screen automatically reflexes to a titer, which reports the antibody level in more detail rather than a simple positive or negative.
This test isn't part of the Celio Health store at the moment, so it can't be ordered or requested here. The test menu lists everything that can.
Laboratory results should always be interpreted by a licensed clinician who knows your health history. This page is information about a test, not medical advice.
Frequently asked questions
What does this test measure?
It detects antibodies to double-stranded DNA (dsDNA) in serum, using an immunofluorescence assay. Quest associates these antibodies with active systemic lupus erythematosus and, in some patients, mixed connective tissue disease.
How is the sample collected?
The test uses a serum sample from a routine blood draw.
Do I need to prepare for this test?
Quest lists preparation for this test: an overnight fast before the blood draw is preferred when possible.
What happens if the DNA (ds) antibody screen is positive?
Quest reflexes a positive screen to a DNA (ds) antibody titer on the same sample, which gives a more detailed antibody-level result.
Does this test diagnose lupus on its own?
No. A clinician reads a dsDNA antibody result alongside symptoms, history and other tests; the result on its own does not diagnose a condition.