What is ankylosing spondylitis?

Ankylosing spondylitis (AS) is a type of arthritis that affects the spine. Ankylosing means stiff or rigid, spondyl means spine, and itis refers to inflammation. The disease causes inflammation of the spine and large joints, resulting in stiffness and pain. The disease may result in erosion at the joint between the spine and the hip bone. This is called the sacroiliac joint. It may also cause bony bridges to form between vertebrae in the spine, fusing those bones. Bones in the chest may also fuse.

What causes ankylosing spondylitis?

The cause of AS is not known, but researchers think that genes play a role. A gene called HLA-B27 happens in over 95% of Caucasian Americans who have AS, but only 50% of African Americans who have the disease. However, some people with the HLA-B27 gene do not have AS.

Who is at risk for ankylosing spondylitis?

AS is more common among people ages 17 to 35. It can happen in children and older adults as well. The disease affects more young men than women. It tends to run in families.

What are the symptoms of ankylosing spondylitis?

Symptoms of AS tend to go away and come back over periods of time. Symptoms can occur a bit differently in each person. The symptoms may include:

• Back pain, usually most severe at night during rest
• Early morning stiffness
• Stooped posture in response to back pain (bending forward tends to relieve the pain)
• Straight and stiff spine
• Inability to take a deep breath, if the joints between the ribs and spine are affected
• Appetite loss
• Weight loss
• Fatigue
• Fever
• Anemia
• Joint pain
• Mild eye inflammation
• Organ damage, such as to the heart, lungs, and eyes
• Skin rashes
• Gastrointestinal illness (such as Crohn's or ulcerative colitis)

The symptoms of ankylosing spondylitis can be like other health conditions. Make sure to see your healthcare provider for a diagnosis.

How is ankylosing spondylitis diagnosed?

The process starts with a medical history and a physical exam. Tests may also be done, such as:

• X-ray. This test uses a small amount of radiation to create images of internal tissues, bones, and organs onto film.
• Erythrocyte sedimentation rate (ESR or sed rate). This test looks at how quickly red blood cells fall to the bottom of a test tube. When swelling and inflammation are present, the blood's proteins clump together and become heavier than normal. They fall and settle faster at the bottom of the test tube. The faster the blood cells fall, the more severe the inflammation. Up to 70% of people with AS have a high ESR.
• Genetic testing. Genetic testing is done to find if a person carries a copy of an altered gene for a disease. The gene HLA-B27 is found in over 95% of people with AS.

How is ankylosing spondylitis treated?

Treatment will depend on your symptoms, your age, and your general health. It will also depend on how severe the condition is. The goal of treatment is to reduce pain and stiffness, prevent deformities, and maintain as normal a lifestyle as possible. Treatment may include:

• Nonsteroidal anti-inflammatory medicines, to reduce pain and inflammation
• Tumor-necrosis-factor blockers (biologic medicines, to reduce inflammation and swelling
• Interleukin-17A (IL-17A) inhibitors, to reduce inflammation and swelling
• Disease-modifying antirheumatic medicines (DMARDs), such as sulfasalazine, to decrease inflammation and control AS
• Short-term use of corticosteroids, to reduce inflammation
• Short-term use of muscle relaxants and pain relievers, to relieve severe pain and muscle spasms
• Surgery to replace a joint, place rods in the spine, or remove parts of the thickened and hardened bone
• Maintaining of proper posture
• Regular exercise, including exercises that strengthen back muscles

Talk with your healthcare providers about the risks, benefits, and possible side effects of all medicines.

What are the complications of ankylosing spondylitis?

Over time, a forward curve of the spine can develop with AS. Patients with AS are at great risk of thinning of the bones (osteoporosis). This can result in spinal fractures. AS can also lead to psoriasis, and inflammation of the eye, aortic valve, and intestinal tract.

Living with ankylosing spondylitis

There is no cure for AS, so it is important to work on a treatment plan with your healthcare provider. Work on lifestyle changes that can improve your quality of life. Stay active and keep up with exercise to reduce pain. A physical therapist can help you design an exercise plan and assist you in keeping good posture.

When should I call my healthcare provider?

If your symptoms get worse or you have new symptoms, let your healthcare provider know.

Key points about ankylosing spondylitis

• Ankylosing spondylitis is a type of arthritis that affects the spine.
• A gene may be part of the cause of AS.
• Symptoms of AS include back pain, early morning stiffness, and a stooped posture.
• AS can cause other symptoms such as appetite loss, weight loss, fatigue, fever, anemia, eye inflammation, and GI illness.
• The goal of treatment for AS is to reduce pain and stiffness, prevent deformities, and maintain as normal a lifestyle as possible.
• Staying active is important in the management of AS.

Next steps

• Know the reason for your visit and what you want to happen.
• Before your visit, write down questions you want answered.
• Bring someone with you to help you ask questions and remember what your provider tells you.
• At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you.
• Know why a new medicine or treatment is prescribed, and how it will help you. Also know what the side effects are.
• Ask if your condition can be treated in other ways.
• Know why a test or procedure is recommended and what the results could mean.
• Know what to expect if you do not take the medicine or have the test or procedure.
• If you have a follow-up appointment, write down the date, time, and purpose for that visit.
• Know how you can contact your provider if you have questions.