Arthritis - juvenile

What is juvenile idiopathic arthritis?

Juvenile idiopathic arthritis (JIA) is a group of conditions that cause joint pain and swelling in children and teens under the age of 16, for unknown reasons (idiopathic means 'of unknown cause').

Most people think that arthritis only affects older people. In fact, one in 800 Australian children has a form of juvenile idiopathic arthritis.

Other names for juvenile idiopathic arthritis include juvenile arthritis, juvenile rheumatoid arthritis, juvenile chronic arthritis, and Still’s disease.

Causes of juvenile idiopathic arthritis

We don’t really know what causes JIA, but we do know that it occurs as a result of a malfunctioning immune system.

Your immune system is designed to identify foreign bodies (like bacteria and viruses) and attack them to keep you healthy. However, in the case of JIA, the immune system mistakenly attacks healthy tissue in and around the joints, causing ongoing inflammation and pain.

Symptoms of juvenile idiopathic arthritis

The symptoms your child experiences will depend on the type of arthritis they have. Common symptoms include:

• pain, swelling and stiffness in one or more joints
• skin over the affected joints may be warm or red
• mental and physical tiredness, or fatigue.

Less common symptoms include:

• fever
• rash
• feeling generally unwell
• eye inflammation (uveitis).

Types of juvenile idiopathic arthritis

There are different types of JIA, including:

• oligoarticular JIA
• systemic onset JIA
• polyarticular JIA
• enthesitis-related JIA
• psoriatic JIA
• undifferentiated JIA.

Oligoarticular JIA

This is the most common form of JIA. Few joints are affected. It's also sometimes called pauciarticular JIA ('oligo' and 'pauci' mean 'not many' or 'few').

The characteristics of oligoarticular JIA include:

• starts between the ages of 2 and 4
• is more common in girls
• most often affects larger joints such as knees, ankles, wrists or elbows
• there is the risk of an eye condition called uveitis, which involves inflammation of the inner eye.

The 2 types of oligoarticular arthritis (based on the number of joints involved) are:

• persistent oligoarticular arthritis – no more than 4 joints are inflamed 6 months after diagnosis
• extended oligoarticular arthritis – 5 or more joints are inflamed after 6 months from diagnosis.

Polyarticular JIA

Polyarticular JIA affects 5 or more joints. 'Poly' means many.

The characteristics of polyarticular JIA include:

• starts between the ages of one and 12 years
• is more common in girls
• affects small and large joints
• may cause tiredness and feeling generally unwell.

There are 2 types of polyarticular JIA based on whether rheumatoid factor (RF) is found in the blood. These are:

• polyarticular JIA – rheumatoid factor negative
• polyarticular JIA – rheumatoid factor positive.

Systemic JIA

Systemic JIA can affect many areas of the body, not just the joints. It's the least common type of juvenile idiopathic arthritis.

The characteristics of systemic JIA include:

• affects boys and girls equally
• affects joints and other parts (systems) of the body such as the skin or internal organs
• often causes a fever, tiredness and a skin rash.

Enthesitis-related JIA

Enthesitis means inflammation of the places where tendons attach to bone (entheses).

The characteristics of enthesitis-related JIA include:

• tends to target the large joints of the legs, the spine and the entheses
• is more common in boys
• usually develops in late childhood or adolescence
• associated with red painful eye condition (acute uveitis).

Psoriatic JIA

Children with psoriatic JIA have inflammatory arthritis of the joints, and the skin condition psoriasis.

The characteristics of psoriatic JIA include:

• the psoriasis and arthritis may not develop at the same time
• is more common in girls
• develops in preschool children, or at around 10 years of age
• there may be a family history of psoriasis
• possible pitting of fingernails or toenails – small dents in the nails
• usually affects fingers, wrists and toes, but may affect other joints too.

Undifferentiated JIA

This is where the condition does not fit any of the other types of juvenile idiopathic arthritis.

Diagnosis of juvenile idiopathic arthritis

Juvenile idiopathic arthritis is diagnosed using a number of tests, including:

• medical history
• physical examination
• blood tests
• x-rays and scans
• eye examination.

Treatment for juvenile idiopathic arthritis

There's no cure for JIA, but treatment can help manage symptoms. Working closely with your healthcare team will lead to the best outcomes for your child. Doctors, nurses, physiotherapists, occupational therapists, dietitians, podiatrists, psychologists and social workers may all be a part of your child's healthcare team.

As there are different types of JIA, and the effects of each are different, treatment needs to be tailored to each child.

Medication

Most children with JIA – regardless of the type – will have to take some form of medication at some time. It depends on the symptoms they’re experiencing. There are many different types of medication that work in different ways.

Your doctor will always start with the simplest medications at the smallest doses and work their way up to more complex medications and larger doses depending on how your child's condition responds to the treatments.

The most common types of medications used for JIA are:

• Pain-relievers (analgesics) – for temporary pain relief.
• Creams and ointments – can be rubbed into the skin over a painful joint to provide temporary pain relief.
• Eye drops – to treat eye inflammation.
• Non-steroidal anti-inflammatory drugs (NSAIDs) – to control inflammation and provide pain relief.
• Corticosteroids – used to quickly control or reduce inflammation. They can be taken as tablets or given by injection directly into a joint, muscle or other soft tissue.
• Disease modifying anti-rheumatic medications (DMARDs) – work on controlling the immune system. These medications help relieve pain and inflammation, and can also reduce or prevent joint damage.
• Biologics and biosimilar medicines (bDMARDs) – are also a type of disease modifying drug. They also work on controlling the immune system. However, unlike other disease modifying drugs, biologics target specific cells and proteins that are causing the inflammation and damage, rather than suppressing the entire immune system.

Self-management of juvenile idiopathic arthritis

There are many things you and your child can do to manage their condition.

• Follow the plan that your health professionals have developed. That means taking medications as they’ve been prescribed, doing the exercises the physiotherapist or occupational therapist have provided, and letting your doctor know of any changes to your child’s symptoms and how they’re feeling. All of these things give your child a better chance of managing their JIA well and reducing the risk of long-term problems.
• Stay active. Physical activity is the key to maintaining muscle strength, joint flexibility and managing pain. A physiotherapist or exercise physiologist can help design an individual program for your child.
• Learn ways to manage pain. There are many strategies you can use to help your child deal with pain. From heat and cold treatments, distraction, massage and medication, there are many ways your child can manage pain.
• Eat well. While there’s no diet that can cure JIA, a healthy and well-balanced diet is the best for good health. Keeping to a healthy weight is also important as extra weight puts added strain on your child’s joints, especially load bearing joints such as the hips, knees and ankles.
• Protect joints. Find out about aids, equipment and gadgets that can make tasks easier. An occupational therapist can give you advice.
• Stay at school. It’s good for your child’s health and wellbeing. Talk to your doctor, allied health professionals and teachers about ways to help your child stay at school, and keep up with school.

Where to get help

• Your GP (doctor)
• Paediatric rheumatologist
• Caring for a child with arthritis and other musculoskeletal conditions, Musculoskeletal Health Australia's school resource
• Musculoskeletal Health Australia - B.A.M Helpline. Tel. 1800 263 265