Ankylosing Spondylitis Blood Test Results Explained


Ankylosing Spondylitis [AS] is a progressive form of arthritis. It typically causes a chronic form of inflammation that affects the joints of the spine. It has also been known to spread to organs and other joints, but primarily affects the ligaments and joints of the skeleton. Most people who have AS have pain, aching, and stiffness around the spine, pelvis, and hips. If left untreated, it has been known to fuse the spine and calcify ligaments.

AS is a disease that generally affects men under the age of 40. It is 9x more common in men than it is in women and generally has onset between the ages of 17-35. If women do develop AS, the most common time to experience the first symptoms of the disease is during their first pregnancy. The Ankylosing Spondylitis blood test measures the HLA-B27 gene to determine if there are markers present that indicate a risk for AS or to confirm its diagnosis.

Up to 95% of people who have AS will test positive for the HLA-B27 gene.

What Causes Ankylosing Spondylitis?

Because of its genetic component, it is believed that a majority of AS cases tend to be genetic in nature. The only problem is that medical science doesn’t understand as of yet why the disease progresses and spreads or why the spine may eventually become fused. The first symptoms of AS tend to be an inflammation of the bones near the joint that will be affected. As it spreads to new tissues, the bones become weaker and calcium deposits then appear around the inflammation points in an attempt to heal the bone.

For some reason, the calcium deposits follow AS inflammation to ligaments and spinal discs and calcifies them as well. The first symptoms may come and go over several months. Movement, especially during the first symptoms, tends to improve the pain and stiffness.

The AS blood test is not designed to say definitively as to whether or not the disease is present. It simply detects the markers for the HLA-B27 gene and if those are present, then a diagnosis is more likely to occur. Some medical providers may also perform other tests to determine the level of inflammation that may be present in the body. A urine test to look for kidney abnormalities that are sometimes associated with AS may also be ordered.

What Do My Test Results Mean?

The AS blood test results will either be positive or negative. A positive test indicates the presence of markers that can only be introduced by the HLA-B27 gene. A negative test indicates that the gene is not present. People who have tested negative have still developed Ankylosing Spondylitis, however, and those with positive test results have never developed the disease.

A medical provider will evaluate specific test results with an individualized medical history to determine specific risks. A family history will also be part of the evaluation process. From there, test results will then be translated into a treatment plan if needed.

The Facts About Ankylosing Spondylitis

About 1 in 2,000 people born in the United States are going to be affected by AS at some point in their lives. It can strike at any age and affect anyone, even though young men are the most susceptible and experience the most severe forms of the disease. Because 1 in 6-8 people in the US have the HLA-B27 gene, AS tends to run in families and relatives may have different forms of arthritis diagnosed instead, including rheumatoid arthritis.

Early diagnosis of AS leads to a good prognosis. Most people who are diagnosed with this condition never need to be hospitalized because of it. Pain relief is a primary treatment plan goal and special exercises are often assigned to help maintain spinal mobility. Most treatments involved over-the-counter NSAID anti-inflammatory drugs.

The goal is to prevent the forward curvature of the spine as AS continues to spread. This often means learning how to sit properly, not sleeping with a pillow at night, and performing low impact exercises that do not create an impact on the spine. High levels of activity are encouraged, as are deep breathing exercises, and prolonged sitting and bed rest are to be avoided.

Surgery is often a last resort option for treating AS. It is typically used only to correct a severe deformity that prevents a person from standing or looking forward.

The Ankylosing Spondylitis blood test may not be a specific screening tool, but it does provide useful information that can lead toward a diagnosis. Be sure to speak with a medical provider about chronic lower back pain that doesn’t go away despite movement or stretching and then discuss what the results from this test mean to your medical history so that a treatment plan for AS can be developed.