The HLA-B27 Antigen test contains 1 test with 1 biomarker.
Description: The HLA-B27 Antigen test is a blood test that tests for the presence of human leukocyte antigen B27 on the surface of a person’s white blood cells.
Collection Method: Blood Draw
Specimen Type: Whole Blood
Test Preparation: No preparation required
When is an HLA-B27 Antigen test ordered?
When a patient experiences acute or persistent pain and inflammation in the spinal vertebrae, chest, neck, eyes, and/or joints, and the doctor feels the cause is an autoimmune illness linked to the existence of HLA-B27, an HLA-B27 test may be prescribed. When someone has recurrent uveitis, an HLA-B27 test may also be required.
When doctors suspect ankylosing spondylitis however the disease is in its early stages and the vertebrae in the spine have not yet developed the distinctive alterations that would be visible on X-ray, they usually employ the HLA-B27 test result.
What does an HLA-B27 Antigen blood test check for?
On the surface of cells, there is a particular protein called HLA-B27. The gene that produces the HLA-B27 protein is sometimes referred to as HLA-B27. The HLA-B27 test examines whether a person's white blood cells have the HLA-B27 protein on their surface or not.
Human leukocyte antigens are proteins that assist the immune system of the body in recognizing and differentiating between "self" and "nonself" cells. The many antigens found on each person's cell surfaces are encoded by an inherited mix of HLA genes. Each person has a unique HLA combination depending on the presence or absence of each antigen.
Approximately 6% of Americans have the HLA-B27 gene. Autoimmune conditions such ankylosing spondylitis, juvenile rheumatoid arthritis, reactive arthritis, and isolated acute anterior uveitis are more common in those with HLA-B27. Inflammatory bowel disease and a number of other chronic diseases have also been connected to HLA-B27.
Reactive arthritis and ankylosing spondylitis are two chronic, progressive diseases that affect males more frequently than women. The early 30s are the normal age when the first symptoms appear. It can take years for the typical degenerative changes to bones and joints to become obvious on X-rays, and the initial symptoms of these autoimmune illnesses are frequently mild.
- Pain, inflammation, and a progressively hardening of the spine, neck, and chest are the hallmarks of ankylosing spondylitis.
- A collection of symptoms known as reactive arthritis include skin rashes, urethral, ocular, and joint inflammation.
- A type of arthritis that affects children is called juvenile rheumatoid arthritis.
- Recurrent inflammation of the tissues in one or both eyes is a symptom of anterior uveitis.
There is a higher prevalence of the antigen in those who are affected, despite the fact that HLA-B27 has not been proven to be the cause of any of these ailments. For instance, 80–90% of persons with ankylosing spondylitis are HLA-B27 positive, despite the fact that only 6% of the general population carries this gene.
Lab tests often ordered with an HLA-B27 Antigen test:
- Sed Rate
- C-Reactive Protein
- Rheumatoid Factor
- HLA Testing
Conditions where an HLA-B27 Antigen test is recommended:
- Autoimmune Disorders
- Ankylosing Spondylitis
- Reactive Arthritis
- Juvenile Rheumatoid Arthritis
How does my health care provider use an HLA-B27 Antigen test?
The HLA-B27 test is typically requested to support or confirm a suspected diagnosis of reactive arthritis, juvenile rheumatoid arthritis, ankylosing spondylitis, or occasionally anterior uveitis. The HLA-B27 test is non diagnostic, meaning that it cannot be used to provide a firm diagnosis or exclude a condition. The outcome provides additional information and is one piece of evidence that is utilized in conjunction with the assessment of signs, symptoms, and other laboratory tests to confirm or disprove the diagnosis of specific autoimmune illnesses, such as reactive arthritis and ankylosing spondylitis.
A series of tests, including the HLA-B27 test, may be requested to help identify and assess diseases that result in arthritis-like symptoms such chronic joint pain, feeling stiff, and inflammation. Rheumatoid factor testing using either an erythrocyte sedimentation rate or a C-reactive protein may be part of this set of tests. When evaluating a patient with recurrent uveitis that is not brought on by a known disease etiology, HLA-B27 may occasionally be requested.
What do my HLA-B27 test results mean?
A positive HLA-B27 test indicates that the subject is more likely to acquire specific autoimmune illnesses. Ankylosing spondylitis, arthritis, or another autoimmune illness linked to the presence of HLA-B27 may be diagnosed if the patient exhibits symptoms including chronic pain, inflammation, and/or degenerative changes to the bones. This is particularly true if the individual is young, male, and had his initial symptoms before to the age of 40.
A negative HLA-B27 test indicates that the marker was not found. However, as people without the HLA-B27 antigen can also develop various autoimmune disorders, this does not necessarily imply that the person who was tested does not have the suspected condition. The HLA-B27 antigen carries no guarantee that a person will experience any of these ailments. Researchers are attempting to identify the causes of these specific diseases as well as the variables that increase the risk of these diseases in people with HLA-B27.
Genetics determines whether or not specific HLA antigens will be present. The generation of those antigens is governed by genes that are passed down from parents to their offspring. Two HLA-B27 positive family members who experience the onset of one of the HLA-B27-related illnesses are more likely to experience the onset of the illness themselves.
We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.
