Juvenile Idiopathic Arthritis

Juvenile idiopathic arthritis (JIA) is the most common type of arthritis that affects children. JIA is a chronic (long-lasting) disease that can affect joints in any part of the body.

Overview #

• JIA is an autoimmune disease in which the body’s immune system mistakenly targets the synovium, the tissue that lines the inside of the joint, and the synovial fluid in the joint.

• This causes the synovium to make extra synovial fluid, which leads to swelling, pain and stiffness in the joint.

• This process can spread to the nearby tissues, eventually damaging cartilage and bone. Other areas of the body, especially the eyes, may also be affected by the inflammation.

• If it is not treated, JIA can interfere with a child’s normal growth and development.

Causes #

The causes of JIA are not known. Factors that may be involved, alone or in combination, include genetics (the disease may be inherited), infection and environmental factors that influence the immune system.

Symptoms #

• Pain, swelling and tenderness in the joints. The joints may also feel warm.

• Morning joint stiffness

• Limping gait (younger children may not be able to perform motor activities that they recently learned)

• Fever

• Rash

• Weight loss

• Swollen lymph nodes

• Fatigue or irritability

• Eye redness, eye pain, and blurred vision

Diagnosis #

• Imaging techniques such as X-rays or magnetic resonance imaging (MRI) to show the condition of the joints,

• Laboratory tests on blood, urine, and/or joint fluid to help determine the type of arthritis.

• These include tests to determine the degree of inflammation and the presence of the substances antinuclear antibody (ANA) and rheumatoid factor.

• These tests also can help rule out other diseases — such as an infection, bone disorder, or cancer or an injury as the cause of the symptoms.

Treatment #

Nonsteroidal anti-inflammatory drugs (NSAIDs) #

• These medicines provide pain relief and reduce swelling, but do not affect the course or prognosis of JIA. Some are available over the counter and others require a prescription.

• NSAIDs include ibuprofen (such as Motrin® and Advil) and naproxen (such as Aleve).

• These medicines can cause nausea and stomach upset in some people and need to be taken with food.

Corticosteroids (steroids) #

• Corticosteroids are often given as an injection (shot) into a single affected joint.

• These medications can also be taken orally (by mouth) as a pill, especially by patients with more widespread disease.

• Oral corticosteroids can have serious side effects, including weakened bones, especially when used for long periods.

• Doctors usually try to limit using long-term steroids in children because they can interfere with a child’s normal growth.

Disease-modifying anti-rheumatic drugs (DMARDs) #

• These medications work by changing, or modifying, the actual disease process in arthritis

• The aim of DMARD therapy is to prevent bone and joint destruction by suppressing the immune system’s attack on the joints.

• Methotrexate is the DMARD most often used to treat JIA. Other medications used include sulfasalazine and leflunomide.

Biological modifying agents #

• Biological agents are medications that directly target molecules or proteins in the immune system that are responsible for causing the inflammation.

• They are given by subcutaneous injection or intravenously and are used to treat children with more severe arthritis that has not responded to other medications.

• Biological agents must be used with caution because they suppress the immune system and make children more vulnerable to infection.

• These drugs include etanercept, infliximab, adalimumab, abatacept, anakinra, rilonacept, and tocilizumab.