Ankylosing spondylitis (AS) is an inflammatory condition of the spine which causes pain and stiffness. AS can also cause inflammation, pain, and stiffness in other areas of the body such as the shoulders, hips, ribs, heels, and small joints of the hands and feet. Sometimes the eyes can become involved (known as uveitis), and rarely, the lungs and heart can be affected. It can also be linked to other medical conditions such as inflammatory bowel disease. Other conditions related to AS include psoriatic arthritis, reactive arthritis and juvenile idiopathic arthritis. (see further information links below).
What are the symptoms?
The main symptom is the gradual onset of lower back pain and stiffness over a period of 3 months or longer. These symptoms are often worse when in bed and first thing in the morning. Movement and physical activity often relieves the symptoms. Some people experience fatigue (excessive tiredness) and weight loss. AS is a progressive condition, and symptoms can worsen over time. It can be difficult to diagnose, as back pain is one of the most common presentations at GP surgeries. It is thought that some patients may experience years between onset of symptoms and diagnosis. The use of MRI is becoming more frequently used in the diagnosis of AS, as well as x-rays, clinical history and blood tests. Some patients may present with other issues such as Uveitis (inflammation of the eye), which can lead them on to a diagnosis of AS.
Who is affected?
The disease typically presents in people in their late teens or early adult life. The average age when symptoms start is 24. It affects more men than women: around 1 in 200 men is affected and 1 in 500 women. However it is difficult to produce accurate figures because it is a condition which is challenging to diagnose and often overlooked. The Department of Health’s figures is that there are 200,000 people diagnosed with AS in the UK.
Why does it happen?
The cause of AS remains unknown. There is some link to your genes, but this does not mean that AS is passed directly from adult on to a child. Patients who have been diagnosed with AS are often found to be positive for a genetic marker HLA-B27. However, there are large numbers of the population who would test positive for this genetic marker, and not have AS, so the test in isolation is not used to diagnose AS.
Have I got AS?
You may have inflammatory back pain if you answer yes to at least 4 of the 5 of the statements below.
Back pain of more than 3 months duration is potentially inflammatory if:
If you feel you have inflammatory back pain, it may be appropriate to discuss your concerns with your GP.