Description
Why It’s Done:
The HLA-B27 PCR test is typically ordered to:
• Help diagnose autoimmune and inflammatory disorders, particularly:
o Ankylosing spondylitis
o Reactive arthritis
o Psoriatic arthritis
o Juvenile idiopathic arthritis
o Uveitis (especially recurrent anterior uveitis)
• Support a diagnosis when symptoms include chronic back pain, joint stiffness, or eye inflammation.
• Identify genetic predisposition in patients with a family history of related autoimmune diseases.
Note: A positive HLA-B27 result supports the diagnosis but does not confirm disease on its own. Many people with the gene never develop related conditions.
Preparation:
• No special preparation is typically required.
• You do not need to fast before the test.
• Inform your doctor about any:
o Current medications (though most do not affect the test).
o Symptoms such as joint pain, stiffness, or eye issues.
o Family history of autoimmune conditions.


