Human leukocyte antigen b27 is a supplementary diagnostic indicator for rheumatologic immune diseases, and a positive test means that ankylosing spondylitis, rheumatoid arthritis and other diseases may be present. Human leukocyte antigen b27, or HLA-B27, can be expressed on all nucleated cells in the body, and under normal circumstances, the test result is negative.Positive HLA-B27 test is closely related to rheumatoid immune diseases, which can be seen in ankylosing spondylitis, rheumatoid arthritis, rheumatoid arthritis after intestinal disease, reactive arthritis, etc. However, a positive test does not mean that you have the above diseases, but it does not mean that you are suffering from them. However, a positive HLA-B27 test does not mean that you are suffering from any of the above diseases, but that you are more likely to suffer from them than those who are negative. Specific diseases need to be diagnosed by a medical professional in conjunction with clinical symptoms and imaging tests.