What is HLA-B27?
HLAs are proteins that assist the body's immune system in distinguishing between the body's cells and external microbes. They are produced using instructions provided by inherited genes. Your body creates a protein known as human leukocyte antigen B27 that helps your immune system recognise foreign materials that are regarded as harmful to the body.

To safeguard your body from potential harm, human leukocyte antigens seek to eliminate any cell they identify as "foreign and unsafe." However, individuals with the HLA-B27 antigen are considered prone to contracting diseases like autoimmune hepatitis, ankylosing spondylitis, juvenile rheumatoid arthritis, rheumatoid arthritis type II, lupus erythematosus, or Crohn's disease. Geographical location affects the prevalence of the HLA-B27 allele in individuals, with individuals living in northern latitudes having a higher prevalence.

What is The HLA-B27 Test Procedure?
The procedure for the HLA-B27 test is similar to standard blood-drawing techniques. Trained employees administer it in the clinic using a tiny needle. Typically, they use a

small needle to draw blood from your arm. Your blood is drawn from a vein inside your elbow or the back of your hand and put in a tube before being transported to a lab for testing. No additional preparation is required. However, remember to consult your doctor before taking any medications.

Mild discomfort, soreness/swelling at the injection site, or lightheadedness are the adverse effects seen during the test. The wait time for results is 4–8 days. The length of time depends on the technology being employed, like Flow Cytometry, Sequence-Specific Oligonucleotide Probes (SSOP), or Polymerase Chain Reaction (PCR).

Common Illnesses Due to HLA-B27
When a patient experiences acute or persistent pain and inflammation in their chest, spine, neck, eyes, or joints and their doctor detects an autoimmune condition linked to the existence of HLA-B27, only then may an HLA-B27 test be prescribed. When diagnosing ankylosing spondylitis (AS) and other HLA-B27-related illnesses, doctors frequently depend on their clinical observations and the result of the HLA-B27 test because any unprecedented changes might not be seen for a few years. The HLA-B27 test in this situation does not provide a diagnosis, but it does provide additional information that can either increase or decrease the possibility that the individual has ankylosing spondylitis.

Arthritis is another common illness caused by HLA-B27. It includes inflammation of the vertebrae or spinal joints, which can lead to chronic, ongoing pain and discomfort. Individuals may also suffer from ankylosis, where portions of the spine fuse in a permanent and immovable posture. HLA-B27 is also considered the hallmark of the genetic component of spondyloarthritides, and about 90% of patients with AS carry this antigen.