Juvenile Idiopathic Arthritis

Juvenile Idiopathic Arthritis - What it is

Juvenile Idiopathic Arthritis (JIA) is an autoimmune disease that involves the joints, but can also cause eye inflammation, fevers or rash. JIA is a chronic disease, and by definition, the symptoms of JIA start before the child reaches the age of 16.

Our body’s immune system is normally responsible for fighting foreign bacteria, viruses and diseased cells in the body. In JIA, malfunctioning of the immune system causes it to target the body’s own cells, thus attacking the lining of the joints (synovial membrane) and causing inflammation. If the inflammation is left untreated, the condition progresses, leading to destruction of the bone and cartilage of the joint, and ultimately loss of function or mobility. The swelling and tenderness is due to increased fluid in the joint and the thickening of the joint capsule.

Juvenile Idiopathic Arthritis - Symptoms

Typical symptoms of JIA include joint pain, swelling and stiffness that last for more than 6 continuous weeks. Stiffness is typically worse in the morning or after a nap. JIA tends to affect the knees, hands and feet, and may involve only a few joints or several joints at a time. The child may have difficulty walking, is reluctant to use a limb, or be struggling with fine motor skills. Chronic arthritis in a growing child can potentially lead to localized growth failure which can result in leg length discrepancy (and this could be permanent).

A small group of children with JIA (approximately 10%), have a systemic form of the disease that is characterised by fever and rash in addition to arthritis. The rash and fever may appear before the joint symptoms, but the arthritis may persist even after the fever and rash have disappeared. Some other symptoms in the systemic form of the disease may include liver, spleen or lymph nodes enlargement and inflammation of the membranes around the lungs (pleuritis) and the heart (pericarditis).

Juvenile Idiopathic Arthritis - How to prevent?

As we do not fully understand the cause of JIA, there is no way to prevent its onset. However, the disabilities caused by JIA can be prevented with early diagnosis and treatment. A healthy balanced diet and regular exercise are also helpful.

Family members can do several things to help a child with JIA physically and emotionally:

Seek medical treatment early. The best care for your child with JIA is provided by a rheumatology team.
Learn and understand as much as you can about your child's disease and its treatment.
Ensure that your child takes his / her medication as prescribed by the doctor.
Encourage physical activity and exercise. Work with therapists and other healthcare providers involved in your child's care.
Treat the child as normally as possible to foster a positive outlook.

JIA can cause complications such as serious eye inflammation called uveitis. The eye inflammation can sometimes be silent. It is important to recognize this complication early, which highlights the importance of undergoing regular eye checks by an ophthalmologist.

Juvenile Idiopathic Arthritis - Causes and Risk Factors

The exact causes of JIA are unknown. In certain arthritis, the malfunctioning of body's immune system may be due to a trigger such as a viral infection which can set off the condition.

Like other autoimmune diseases, JIA may be linked to genetic factors associated with an abnormal immune response. A family history of JIA and / or other autoimmune diseases are risk factors, but there is no precise way of predicting how high the risk is if there is an affected member in the family.

Juvenile Idiopathic Arthritis - Diagnosis

The diagnosis of JIA is made by taking a detailed medical history, doing a physical examination to look for signs of joint inflammation, and excluding other conditions that can mimic JIA. There is no blood test that can be used to diagnose or confirm JIA.

Your doctor may perform the following tests to aid in making the diagnosis and to determine the severity of the disease:

Blood tests to assess the degree of inflammation (e.g., C-reactive protein (CRP), Erythrocyte Sedimentation Rate (ESR), full blood count),
Autoantibodies (e.g. anti-nuclear antibody, rheumatoid factor)
X-rays or magnetic resonance imaging (MRI) scans to detect unusual bone development, joint damage and soft tissue abnormalities.

Juvenile Idiopathic Arthritis - Treatments

There is no cure yet for JIA. However, there are various treatment strategies to alleviate symptoms, prevent joint destruction and maintain joint function and mobility. There may be periods when the symptoms improve or disappear (remission) and times when symptoms get worse (flares).

Medication

NSAIDs(non-steroidal anti-inflammatory drugs), such as ibuprofen, naproxen or diclofenac, are prescribed to reduce pain and stiffness, and therefore helpful in helping the child feel more comfortable. However, these drugs will not have any benefit in preventing long term progression of the disease. When only 1 or 2 joints are involved, steroid injected directly into the joint can also be very effective.

Depending on the severity and progression of the disease, DMARDs (disease-modifyng anti-rheumatic drugs) are often necessary and are added as a second-line treatment. These include methotrexate and sulfasalazine. Such drugs can slow the progression of the disease and prevent arthritis flares, but they do take several weeks to reach their full effect. Corticosteroids, such as prednisolone may be used for short duration whilst waiting for the DMARDs to take effect. Due to the potential side effects, the duration of use of corticosteroids, such as prednisolone, should generally be kept as short as possible.There is also a group of more recently developed advanced therapy called biologic agents, such as etanercept, infliximab, and anakinra. These drugs are very effective for JIA and are given as injections. It is important to note that all these medications need to be monitored by your doctor for side effects and toxicity. Discuss with the rheumatologist treating your child on the best treatment for him/her.

Exercise and Physical Activity

In the management of JIA, physiotherapists and occupational therapists play important roles. Once the joint inflammation is controlled, it is important to regain muscle strength previously weakened by the arthritis. Exercise helps to build muscle strength and endurance which is needed for joint stability and recovery of range of motion. Splints and other devices are sometimes useful to prevent joint contractures and deformities.

Most children with JIA can take part fully in physical activities and selected sports when the arthritis is under control. Swimming is particularly useful because it uses many joints and muscles without putting weight on the joints. During a disease flare, limiting certain activities may be necessary. An acutely swollen and painful joint should be rested. Once the flare is over, the child can start regular activities again.