Juvenile Ankylosing Spondylitis

What is juvenile ankylosing spondylitis?

Juvenile ankylosing spondylitis (JAS) is a type of arthritis that affects the spine and the sites where the muscles, tendons, and ligaments are attached to bone.

  • Ankylosing means stiff or rigid.

  • Spondyl means spine.

  • Itis refers to inflammation.

The disease causes inflammation of the spine and large joints, resulting in stiffness and pain. The disease may wear away the joint between the spine and the hip bone (the sacroiliac joint). It may also cause bony bridges to form between vertebrae in the spine. These bony bridge can fuse the bones together. Bones in the chest may also fuse.


Both genetic and environmental factors cause JAS. It tends to run in families and males are affected by JAS 3 times more often than females.

Who is affected by juvenile ankylosing spondylitis?

JAS strikes young people, typically between ages 17 and 35, but it also may affect adolescents. JAS is thought to affect males more often than it does females.

What are the symptoms of juvenile ankylosing spondylitis?

Symptoms of JAS tend to come and go over time.  While, each child may experience symptoms differently, these are the most common:

  • Pain in the back, joint, buttocks, thighs, heels, or near shoulders

  • Early morning stiffness

  • Trouble standing up straight

  • Trouble taking a deep breath

  • Appetite loss

  • Weight loss

  • Fatigue

  • Fever

  • Eye pain, redness, and sensitivity to light

  • Organ damage, such as the heart, lungs, and eyes

Symptoms of juvenile ankylosing spondylitis may look like other medical conditions or problems. Always consult your child's doctor for a diagnosis.

How is juvenile ankylosing spondylitis diagnosed?

In addition to a complete medical history and physical exam, other tests done to diagnose JAS include:

  • X-rays. A diagnostic test that uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.

  • Erythrocyte sedimentation rate (ESR or sed rate). This test is done to determine if there is inflammation in the body. It's done by measuring 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. Thus, when measured, they fall and settle faster at the bottom of the test tube. Generally, the faster the blood cells fall, the more severe the inflammation. People with JAS often have an elevated ESR.

  • Detection of (HLA-B27) antigen. This is a blood test for certain autoimmune conditions. HLA-B27 is an antigen. This is a substance that causes the body to produce antibodies to fight bacteria, viruses, and other "foreign" particles to prevent infection. If this antigen is present, it may indicate some type of autoimmune disease.

Treatment for juvenile ankylosing spondylitis

The goal of treatment for JAS is to reduce pain and stiffness, prevent deformities, and help your child maintain as normal and active a lifestyle as possible.

Specific treatment for juvenile ankylosing spondylitis will be determined by your child's doctor based on:

  • Your child's overall health and medical history

  • Extent of the condition

  • Your child's tolerance for specific medications, procedures, and therapies

  • Expectation for the course of the disease

  • Your opinion or preference

Treatment may include:

  • Nonsteroidal anti-inflammatory medication, NSAIDs, (to reduce pain and inflammation)

  • Short-term use of corticosteroids (to reduce inflammation)

  • Disease modifying antirheumatic drugs (DMARDS), such as methotrexate or biologics, such as infliximab or etanercept. These drugs slow down inflammation in the body.

  • Regular exercise, including exercises that strengthen back muscles

  • Physical therapy