Often when you hear the term arthritis, you think of a condition that affects you later in life.However, there is a form of arthritis that can affect children called juvenile idiopathic arthritis, also referred to as JIA. It’s not a single disease, but rather a group of disorders.
JIA is the most common type of arthritis and it can affect many different parts of the body. Patients diagnosed with JIA have symptoms that can involve just one or many joints, that begin before 16 years of age, and that last for at least 6 weeks. JIA has no known cause. One of the most common symptoms of JIA is inflammation of the synovium, which is the tissue that lines and makes fluid to lubricate the joint. If the synovium becomes very inflamed, it eventually can lead to extensive damage of the joint.
X-rays of the joints can show changes of advanced disease, such as bone destruction and narrowed joint spaces. However, the relatively recent development of new therapies can treat the disease before irreversible joint damage occurs, so it is important to make the diagnosis early. For this reason, MRI and ultrasound are often used to evaluate children who might have or are known to have JIA. Both of these imaging methods can show even a small amount of joint inflammation (which can be difficult to see on x-rays) and are extremely helpful tools to help make the diagnosis, to see disease progression, and to monitor if treatment is effective.
At Cincinnati Children’s, we work very closely with the rheumatologists who treat these patients, and are very experienced with imaging children affected by JIA. The MRI images above show a knee from an adolescent girl with JIA. The picture on the left shows a large amount of joint fluid (arrow). An MRI of the same knee (picture on the right) done 6 weeks after the start treatment shows that the joint fluid is almost gone (arrow). This information helped her doctors know that the therapy she is getting is effective.
While there is no definitive “cure” for JIA, the symptoms can be reduced and damage to joints can be greatly limited. Some children do go into remission and remain asymptomatic throughout their lives, but many will have some level of arthritis into adulthood. Radiology is committed to aiding in catching JIA early so minimal damage occurs.
Contributed by Dr. Tal Laor and edited by Bessie Ganim (RT-NUC).