Antibody Screening for Autoimmune Conditions (e.g., Lupus, Rheumatoid Arthritis) via Immunoassay
This test checks for certain antibodies in your blood that may indicate an autoimmune condition, where your immune system mistakenly attacks healthy tissues.
["Helps identify possible autoimmune diseases by detecting abnormal antibodies in your bloodstream."]
Key facts at a glance
- LOINC
- 83084-4
- Short code
- CA19-9
- Synonyms
- Cancer Ag19-9 SerPl IA-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Serum separator tube (SST) or red-top clot tube; plasma may be collected in heparin or EDTA tubes per assay specification
- Units
- N/A
- Ref low
- 0
- Ref high
- 37
- Critical range
- 0.5 N/A – 1000 N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- Immunoassay (e.g., chemiluminescent immunoassay, electrochemiluminescence immunoassay, or radioimmunoassay)
- CPT
- 86301
- SNOMED
- 1153300007
- Specimen volume
- 1-2 mL of serum or plasma (minimum 0.5 mL)
- Stability
- Room temperature: 24 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 3 months. Avoid repeated freeze-thaw cycles.
- Hemolysis max
- 100
- Lipemia max
- 200
- Icterus max
- 30
- TAT
- 4–24 hours
- Order
- routine
What This Test Measures
The test uses an immunoassay method to detect specific antibodies in your serum or plasma. It screens for a range of potential autoimmune markers, though the exact antibodies tested may vary by lab. This is often part of a broader autoimmune workup.
Why It Might Be Ordered
Your healthcare provider may recommend this test if you have symptoms like joint pain, fatigue, rash, or other signs of autoimmune disease, or if you have a family history of such conditions.
Common Symptoms to Watch For
Symptoms like persistent fatigue, unexplained joint or muscle pain, skin rashes, or swelling may prompt this screening. Autoimmune diseases can affect many body systems, so symptoms vary widely.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast for 8–12 hours if your blood is drawn early in the morning. Wear a loose shirt for easy access.
Reference range
Generally <37 U/mL (or <37 kU/L) is considered normal for healthy adults; reference values may vary by assay manufacturer. Values can be mildly elevated in benign conditions (e.g., pancreatitis, biliary obstruction, liver disease).N/A
No fasting required. Specimen should be collected prior to initiation of chemotherapy, radiotherapy, or surgical intervention when used for monitoring. Avoid hemolyzed, lipemic, or icteric samples when possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Positive results suggest the presence of antibodies that may indicate an autoimmune condition. However, further testing (like confirmatory assays) and clinical correlation are needed to diagnose a specific disease. False positives can occur, so results should always be discussed with your doctor.
Short name
Autoimmune Antibody Screen
Frequently asked questions
What does a positive result mean?
Can I eat or drink before this test?
How long will it take to get results?
Sources
- 1
- 2Lab Tests OnlineSource
- 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 17, 2026. · Read our editorial policy