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Serum β₂-Glycoprotein I Antibody (Qualitative)

Published: August 9, 2026Updated: August 16, 2026

This test detects antibodies against β₂-glycoprotein I, a protein involved in blood clotting and immune responses. It may be used to evaluate conditions like antiphospholipid syndrome.

Quick summary

["This test helps identify certain autoimmune-related blood clotting disorders."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
56538-2
Short code
B2 Glycoprot1 Ab Ser IA-aCnc
Synonyms
B2 Glycoprot1 Ab Ser IA-aCnc
Category
glucose
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
ia
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

This test measures specific substances, cells, or markers in your body to help your healthcare provider learn how well certain organs and systems are working. The results give a clearer picture of your overall health and can help detect, diagnose, or monitor a wide range of medical conditions.

The test measures the presence or absence of antibodies specific to β₂-glycoprotein I in your serum. These antibodies can be linked to conditions affecting blood clotting and immune function.

Your healthcare provider may order this test if you have symptoms that need a closer look, if you are living with a condition that requires regular monitoring, or as part of a routine checkup. It can also be used to screen for health problems before symptoms appear or to find out how well a treatment is working for you.

Your healthcare provider may order this test if you have symptoms or risk factors for conditions like antiphospholipid syndrome, a disorder where the body mistakenly attacks blood clots. It may also be used in research or specialized diagnostic contexts.

Before your test, your healthcare provider will give you specific instructions to follow. Depending on the type of test, you may be asked to avoid eating or drinking for a set amount of time, pause certain medications or supplements, or skip specific activities. Be sure to mention all medicines you take and any allergies you have, and ask questions if anything is unclear.

No special preparation is typically needed. You may have a simple blood draw from a vein in your arm. If you’re on blood thinners, discuss this with your provider beforehand.

Results are often described as normal, meaning your values fall within the expected range, or abnormal, meaning one or more values are higher or lower than expected. An abnormal result does not automatically mean you have a serious health problem. Your provider will review your results with you, explain what they mean, and recommend any follow-up testing or treatment if needed.

Results are qualitative (positive or negative). A positive result indicates the presence of antibodies against β₂-glycoprotein I, which may warrant further evaluation by your healthcare team.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance: Understanding the Role of β₂-Glycoprotein I Antibodies

Short name

β₂-Glycoprotein I Antibody (Qual)

Frequently asked questions

This test is primarily used to support the diagnosis of antiphospholipid syndrome (APS), a rare autoimmune disorder that increases the risk of blood clots. Antibodies against β₂-glycoprotein I are one of several markers (alongside others like lupus anticoagulant) that may be checked together.
A positive result usually means the test detected the substance, marker, or condition it was designed to find. It does not always confirm a diagnosis on its own. Your healthcare provider will consider your symptoms, medical history, and other test results, and may order additional testing to confirm the finding and plan your next steps.
A positive result suggests the presence of these antibodies, which may indicate an increased risk of clotting events. However, further testing and clinical correlation are needed to confirm a diagnosis of APS or related conditions. Results alone do not diagnose a condition.
Whether you need to fast depends on the specific test your provider has ordered. Some tests require no food or drink for 8 to 12 hours beforehand so the results are as accurate as possible, while others allow you to eat normally. Follow the preparation instructions your healthcare team gives you, and call the office if you are not sure whether fasting applies to you.
No fasting is required for this test. Blood is drawn from a vein, and results focus on antibody presence rather than fasting-related variables.
The frequency depends on your healthcare provider’s recommendations. This test may be part of a broader evaluation for autoimmune disorders, performed as needed based on symptoms or clinical suspicion.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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 16, 2026. · Read our editorial policy