Understanding the HLA-B27 Flow Cytometry Test
What It Is: The HLA-B27 Flow Cytometry test is a blood test that identifies the presence of the HLA-B27 protein on the surface of white blood cells. This test uses flow cytometry, a technique that analyzes the physical and chemical characteristics of cells or particles as they flow in a fluid stream through a beam of light.
Why It's Important: The presence of HLA-B27 is associated with certain autoimmune and inflammatory diseases. While not everyone with HLA-B27 will develop these conditions, it can increase the risk of developing diseases such as ankylosing spondylitis, reactive arthritis, and anterior uveitis.
Role of HLA-B27:
Immune System Function: HLAs help the immune system recognize and respond to foreign substances. HLA-B27 can sometimes cause the immune system to attack healthy cells, leading to autoimmune diseases.
Disease Association: HLA-B27 is strongly associated with ankylosing spondylitis and other inflammatory diseases, such as psoriatic arthritis, inflammatory bowel disease, and reactive arthritis.
How the HLA-B27 Flow Cytometry Test Works:
Sample Collection: A healthcare professional collects a blood sample from a vein in your arm.
Laboratory Analysis: The sample is processed in a lab where flow cytometry is used to detect the presence of the HLA-B27 protein on the surface of white blood cells. The cells are labeled with fluorescent antibodies that bind to HLA-B27, and as the cells pass through a laser beam, the fluorescence is measured to determine the presence of HLA-B27.
Advantages of Flow Cytometry:
Increased Sensitivity: Flow cytometry is highly sensitive and can detect even small amounts of the HLA-B27 protein.
Accurate Diagnosis: Flow cytometry provides a precise identification of the HLA-B27 protein, aiding in the diagnosis and management of autoimmune diseases.
Quick Turnaround: Flow cytometry offers faster results compared to some other testing methods.
Why Your Doctor Might Order This Test:
Diagnosing Autoimmune Diseases: To help diagnose conditions like ankylosing spondylitis, reactive arthritis, and psoriatic arthritis.
Monitoring Disease Progression: To monitor the progression of autoimmune diseases and assess the effectiveness of treatments.
Evaluating Symptoms: If you have symptoms such as chronic back pain, joint pain, stiffness, or inflammation, this test can help diagnose the underlying cause.
Symptoms That Might Prompt This Test:
Chronic back pain
Joint pain and stiffness
Inflammation of the eyes (uveitis)
Inflammation of the urethra