What is Juvenile Idiopathic Arthritis?

Juvenile Idiopathic Arthritis (JIA) is a type of chronic arthritis which starts in children and adolescents under the age of 16 years. It is similar to rheumatoid arthritis in adults but is NOT the same disease.

How common is JIA?

In Malaysia, the number of children with JIA is currently not known but in western countries, it generally affects 1 in 1000 children under the age of 16 years.

Who gets JIA?

Both girls and boys can be affected by JIA, but some subtypes of JIA may be more common in girls.

What causes JIA?

The exact cause is unknown and that is why it is called ‘idiopathic’.
However, we do know that JIA :

• is not caused by an infection
• is not caused by eating certain foods
• is not related to events that occurred during a mother’s pregnancy
• does not run in families

What happens in JIA?

In a healthy immune system, our body protects us against infections (e.g bacteria and viruses). It can distinguish between what is part of our body and therefore harmless, and what is foreign and potentially dangerous, which it then destroys. In JIA, the body mistakenly thinks that the joint cells are foreign and hence attacks it resulting in joint inflammation and arthritis. That is why JIA is considered an ‘autoimmune’ disease.

What are the symptoms and signs of JIA?

These include:

• Prolonged fever (with no other underlying cause).
• Pain or swelling over one or more joints including the neck and jaw.
• Stiffness of the joints or body, especially in the morning or after periods of prolonged immobility e.g. sitting in a car.
• Deformities of the joints
• Difficulty in walking or walking with a limp.
• Difficulty in performing normal daily activities like dressing, eating, combing hair or using the hands normally.
• Rashes which appears at the height of fever and subsides after that.
• Visual problems or rarely red eyes.

These symptoms may be due to other diseases and as such your doctor may need to do a series of tests before this diagnosis is made.

How is JIA diagnosed?

Your doctor will examine your child to ensure that he/she has persistent arthritis which has lasted for at least 6 weeks and also carefully exclude any other disease which may look like JIA. This is done by taking a history, examining your child and also performing some laboratory tests.

What tests are done to diagnose JIA?

Unfortunately there is no single test that can diagnose JIA. However various blood and other tests are necessary to provide supportive evidence and also to exclude other diseases that presents with arthritis. A negative autoantibody screen (rheumatoid factor and antinuclear antibodies) in children does not exclude JIA.

What are the potential complications of JIA?

Untreated or poorly controlled JIA can lead to many complications including:

• General poor growth (short stature) and delayed puberty
• Reduced or increased growth of the bones (caused by adjacent inflamed joints) leading to unequal limb length or size.
• Permanent joint damage with resultant joint deformities.
• Blindness (if eye inflammation is not treated).
• A form of severe blood and bone marrow problem(Macrophage Activation Syndrome) with high risk of mortality

How can we treat JIA?

There is currently no cure for JIA. Treatment is aimed at controlling the joint inflammation, allowing the child to lead a normal healthy life and preventing joint damage.

JIA is generally treated with a combination of medications (to control inflammation) and rehabilitation therapy (to preserve joint function and prevent joint deformities). The amount of treatment for each child varies according to the severity and subtype of their disease.

1. Medications
   • Non-steroidal anti-inflammatory drugs (NSAIDs) are often used and it helps reduce inflammation and pain. Examples of NSAIDs are Naproxen, Indomethacin, Diclofenac and Ibuprofen. These drugs commonly cause stomach upset which can be minimized by taking it with food.
   • Corticosteroids are very effective anti-inflammatory drugs which can rapidly reduce the joint inflammation. It can be given by mouth or by a drip (intravenous) if your child is generally ill (systemic disease), for severe polyarthritis or general deterioration. Special preparations can also be injected into swollen joints which can bring about useful short-term relief. Steroid eye drops are also available for eye inflammation as are steroid creams for skin rashes.
     Oral steroids can also cause stomach upset and must be taken with food. If used for long periods at high dosages, they are associated with certain side effects such as weight gain and predisposition to certain infections. However, steroids must NEVER be stopped suddenly without your doctor’s advice as it can be potentially dangerous to your child.
   • Diseases modifying anti-rheumatic drugs (DMARDs) are second line drug treatment given to children with persistent or severe arthritis. These drugs work to reduce the overall activity of the arthritis. They are slower acting and may take months for its effect to work. Examples of these drugs are methotrexate, sulfasalazine, leflunomide and hydroxychloroquine.
   • Newer medications called biologics (e.g. anti-TNF therapy, anti- IL6 therapy) may be useful for selected patients who are not responding to more conventional treatments.
2. Rehabilitation
   • A very important aspect of treatment is physiotherapy and occupational therapy. Physiotherapy is important to maintain joint movement, prevent contractures, increase muscle strength and help with balance. Sometimes physiotherapy can be done in a pool of warm water called hydrotherapy. Occupational therapy with the help of splints can relieve pain, prevent joint deformity and preserve function.

Are there foods which JIA patients cannot take?

There is no necessity to avoid any particular food for JIA. However, make sure that your child has a healthy balanced diet which is required for optimal growth.

Also ensure that the diet contains a good intake of calcium (e.g. milk and cheese) especially for children on corticosteroids to prevent thinning of bones.

Does my child need any ‘supplements’?

Children on long term corticosteroids or who have poor mobility may be at risk for developing osteoporosis and hence may need vitamin D and calcium supplements. Some children especially those with systemic arthritis may need iron supplements. Other supplements are not necessary.
Do consult your doctor before taking any health supplements or complementary therapies as these may interact adversely with your child’s medications.

Can exercise damage my child’s joints?

Exercise is very important for general fitness, maintaining healthy and strong muscles, maintaining movement of joints and helping reduce pain. All children should be encouraged to participate in physical and sporting activities when their joints are not acutely inflamed.

Why does my child need eye checks?

All children with JIA need regular eye screening to look for eye inflammation called ‘uveitis’. Uveitis may not cause any symptoms at all and can also occur even when the arthritis is quiescent.Hence the only way to detect it is by having regular eye check-ups, and how often that occurs depends on your child’s risk for developing uveitis.

Is there a role for surgery?

Surgery is usually not needed for childhood arthritis today as treatment which is available is so much better. However surgery may still be indicated in some instances for example in cases of severe joint damage (may require joint replacement).

Will my child grow out of it?

We know that up to 50-60% of children with JIA will no longer have active arthritis as adults. A smaller percentage will unfortunately continue to have active arthritis even into adulthood. At the moment, we have no way of predicting the future outcome.