What does being HLA-B27 positive mean?

A positive test means HLA-B27 is present. It suggests a greater-than-average risk for developing or having certain autoimmune disorders. An autoimmune disorder is a condition that occurs when the immune system mistakenly attacks and destroys healthy body tissue.

What is the HLA-B27 blood test?

HLA-B27 is a blood test to look for a protein that is found on the surface of white blood cells. The protein is called human leukocyte antigen B27 (HLA-B27). Human leukocyte antigens (HLAs) are proteins that help the body’s immune system tell the difference between its own cells and foreign, harmful substances.

What percent of people are HLA-B27 positive?

The HLA-B27 gene marker is found in approximately 3% to 8% of the population, but it is found in more than 90% of patients with ankylosing spondylitis and in 50% to 80% of patients with other SpAs.

Does HLA-B27 protect against Covid?

HLA-B27 confers some protection against HIV3 and hepatitis C4. However, it does not appear to protect against severe acute respiratory syndrome6,7, which like COVID-19, is attributable to coronavirus.

Which disease is frequently seen in HLA-B27 positive people?

The most notable conditions among these include: ankylosing spondylitis, reactive arthritis (previously referred to as Reiter syndrome), Behçet’s disease, inflammatory bowel disease, and psoriatic arthritis. These conditions fall under the umbrella of seronegative spondyloarthropathies.

Is HLA-B27 associated with lupus?

[14,15] This study, designed to investigate the frequency of IBP and sacroiliitis in SLE, revealed that IBP was increased in lupus patients compared to the healthy population. Human leukocyte antigen B27 and spondylitis susceptibility is one of the strongest known HLA-disease associations.

What is the function of HLA-B 27?

One of its functions is to present antigenic peptides to T-lymphocytes (Fig. 2). HLA-B*27 shows a remarkable polymorphism, with an ever-increasing number of alleles (variants) that show marked differences among racial and ethnic groups worldwide.

What are the side effects of HLA-B27 AU?

Complications in HLA-B27-AU patients are related to the number of recurrent attacks. In a study on the causes of visual impairment and blindness in individuals with intraocular inflammatory diseases, 10 percent of patients with HLA-B27-associated AU suffered legal blindness or severe visual impairment.

How many alleles are there for HLA-B27?

HLA-B*27 shows a remarkable polymorphism, with an ever-increasing number of alleles (variants) that show marked differences among racial and ethnic groups worldwide. As of January 1, 2017, there were 213 known alleles of HLA-B*27 based on nucleotide sequence differences.