HLA-C Typing (Human Leukocyte Antigen C)

Human Leukocyte Antigen B-27 (HLA-B27) is a genetic marker that can indicate a predisposition to a group of inflammatory conditions known as spondyloarthropathies. This test is for individuals experiencing persistent back pain, joint inflammation, or other symptoms suggestive of an autoimmune or inflammatory disorder, as well as those with a family history of such conditions. It is performed using a simple blood sample, with analysis typically carried out by polymerase chain reaction (PCR) or flow cytometry to detect the presence of the HLA-B27 allele.

Biomarkers included

• HLA-B27: A specific protein on the surface of white blood cells. Its presence is associated with an increased risk of developing ankylosing spondylitis, reactive arthritis, and other related inflammatory diseases. However, many people with HLA-B27 never develop these conditions, and the test is used as part of a broader clinical assessment.

Why it matters

Knowing your HLA-B27 status can provide valuable information when used alongside clinical symptoms and other investigations. A positive result may support the diagnosis of a spondyloarthropathy, guiding further evaluation and management. A negative result can help rule out these conditions, especially when symptoms are atypical. This test is not a definitive diagnostic tool on its own, but it offers an important piece of the puzzle for you and your doctor.