DFS70 Antibody Test (Dense Fine Speckled 70)
This blood test measures IgG antibodies against the DFS70 protein to help your doctor evaluate possible autoimmune conditions. It is especially helpful for telling the difference between people with a genuine autoimmune disease and healthy individuals who have positive ANA screening results.
{"DFS70 antibody is a specific blood marker measured in serum","It helps differentiate autoimmune diseases from healthy ANA-positive individuals","A positive result may indicate the presence of an autoimmune condition requiring further evaluation","The test is performed using blood sample collected from a vein","Results should be interpreted by your healthcare provider in context of your symptoms"}
Key facts at a glance
- LOINC
- 108747-7
- Short code
- DFS70 IgG
- Synonyms
- DFS70 IgG Msmt SerPl
- Category
- cardiac
- Sample
- serum
- Container
- Serum separator tube (SST) or red top vacuum tube
- Units
- N/A
- Ref low
- 20
- Ref high
- 40
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- ≥ 18 years
- Method
- Enzyme-linked immunosorbent assay (ELISA) or Indirect immunofluorescence assay (IIFA)
- CPT
- 86255
- SNOMED
- 118618008
- Specimen volume
- 1.0 mL minimum serum volume
- Stability
- Room temperature: 24 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days
- Hemolysis max
- 50
- Lipemia max
- 300
- Icterus max
- 20
- TAT
- 24–72 hours
- Order
- routine
What is this test?
The DFS70 (Dense Fine Speckled 70) antibody test is a blood test that detects the presence of IgG antibodies against the DFS70 protein. This protein is found in the nucleus of cells. The test is often used alongside other autoimmune tests, particularly Antinuclear Antibody (ANA) testing, to help healthcare providers determine whether a patient's symptoms are due to an autoimmune disease.
How is the test performed?
A healthcare professional will draw a small blood sample from a vein in your arm. This sample is then sent to a laboratory for analysis. The test measures the level of DFS70 IgG antibodies in your blood serum. No special preparation is typically required, but follow your doctor's instructions regarding any fasting or medication adjustments.
What do the results mean?
A positive DFS70 antibody result means these antibodies were detected in your blood. Research suggests that the presence of DFS70 antibodies alone may indicate a lower likelihood of having systemic autoimmune diseases like systemic lupus erythematosus (SLE). However, when present with other autoantibodies, it may still be relevant to your condition. Your doctor will interpret this result together with your symptoms, medical history, and other test results.
Why is this test ordered?
This test is typically ordered when a patient has symptoms suggestive of an autoimmune condition, such as joint pain, fatigue, skin rashes, or when initial screening tests like ANA are positive. The DFS70 test helps distinguish between: 1) Healthy individuals who are ANA-positive but don't have autoimmune disease, and 2) Patients with actual autoimmune conditions.
Reference range
Negative: < 1:80 titer or < 20 AU/mL; Equivocal: 1:80 to 1:160 titer or 20-40 AU/mL; Positive: > 1:160 titer or > 40 AU/mLN/A
No special preparation required. Patient does not need to fast. Maintain normal medication regimen unless otherwise instructed by physician.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
DFS70 antibodies are commonly found in healthy individuals with positive ANA tests, suggesting they may be markers for false-positive ANA results rather than disease. However, when detected in patients with clinical symptoms, they may be associated with various conditions including atopic dermatitis, certain infections, and occasionally systemic autoimmune diseases. The presence of DFS70 antibodies alone has been associated with a lower risk of developing systemic lupus erythematosus. Clinical interpretation should always be done in the context of the patient's complete clinical picture.
Frequently asked questions
Do I need to fast before this test?
Is this test painful?
Can DFS70 antibodies be treated or cured?
How long does it take to get results?
Should I be worried if my test is positive?
Sources
- 1
- 2
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 14, 2026. · Read our editorial policy