Juvenile arthritis (JA), the name given to arthritis diagnosed in children through age 16, is thought to affect about 1 in 500 children. The disease’s exact cause is not fully understood, but it is often attributed to a combination of genetic and environmental factors.

Oligoarticular juvenile arthritis — also known as oligoarticular juvenile idiopathic arthritis (JIA) or oligoarthritis — is the most common form of this disease, affecting approximately two-thirds of all patients, especially girls. It typically is also the disease’s mildest form, one that affects four or fewer joints within the first six months of diagnosis, and is usually marked by joint pain and swelling. Onset of oligoarticular JA usually is often seen in early childhood, often before 2 or 4 years of age.

Should symptoms continue in four or fewer joints for longer than six months, the condition is referred to as persistent oligoarticular JA, a subtype of oligoarticular JA. If five or more joints are affected within six months of symptoms, another subtype — extended oligoarticular JA — is likely the cause.

Oligoarticular juvenile arthritis and its symptoms

Oligoarticular JA most commonly affects larger joints, including the knees, ankles, wrists, elbows, and hips. But, especially in children with extended oligoarticular JA, it can also affect finger and toe joints. Symptoms include limping and discomfort when standing and walking, pain and swelling in the joints that lasts for more than six weeks, and overall feelings of weakness, fatigue, and fever. Typically, the affected joints do not incur lasting damage, and most children grow out of the disease by adulthood.

Children with oligoarticular JA, however, are at risk of a serious eye inflammation called uveitis, an inflammation of the middle layer of the eye (called the uvea, and includes the iris). If untreated, uveitis can damage vision and even cause blindness.  About 20 percent of oligoarticular JA patients will develop uveitis.

Uveitis may be difficult to identify because, in about 50 percent of all JA-related cases, it does not cause distinct symptoms: redness or pain in the eye, blurred vision, or unusual light sensitivity. For this reason, children with oligoarticular JA are strongly encouraged to undergo regular eye examinations with an ophthalmologist aware of their disease. Patients with positive antinuclear antibody test results, a test used to evaluate the presence of autoimmune disorders, are thought to be at highest risk of developing uveitis.

How is oligoarticular JA diagnosed?

As with most forms of JA, oligoarticular JA is diagnosed based on an examination of physical symptoms experienced by the patient. This examination typically includes a family history, X-rays or other imaging of affected joints, and may involve blood tests of proteins or chemicals known to be involved in children with JA, such as the antinuclear antibody (ANA) test.

How is oligoarticular JA treated?

Although no cure exists for oligoarticular JA, many therapies do that can be used to ease disease symptoms  and improve quality of life. Physicians may prescribe steroids, or non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen, to limit pain and inflammation. To treat uveitis, steroids in the form of eye drops may be applied directly to the eye. Disease-modifying anti-rheumatic drugs (DMARDs), available in tablet, liquid, or injectable forms, can be used to slow or stop arthritis progression.

Children with oligoarticular JA generally have reduced aerobic and anaerobic capacities. Both high- and low-impact exercise programs have been shown to improve their physical health without exacerbating the symptoms of arthritis.

Note: Juvenile Arthritis News is strictly a news and information website about the disease. It does not provide medical advice, diagnosis or treatment. This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.