Juvenile Idiopathic Arthritis (JIA)

What is juvenile idiopathic arthritis?

Juvenile idiopathic arthritis (JIA) is inflammation (swelling) of one or more of your joints it first occurs before you/ your child’s 16th birthday.

JIA is slightly more common in girls. It most commonly occurs in pre-school age children or teenagers.

There are different types of JIA and symptoms vary between the different types. Knowing which type you/ your child’s has helps assess the likelihood they will grow out of JIA.

JIA may be difficult to control in some people, but most cases will be well controlled with treatment most of the time. If arthritis is part of another condition, it's often managed in a very similar way to JIA.

What should I look out for?

If you/your child has any of these symptoms for more than a couple of weeks, this will be why referral is sent to a paediatric rheumatology consultant

• painful, swollen or stiff joint(s)
• joint(s) that are warm to touch
• increased tiredness
• a fever that keeps returning
• a limp but no injury.

They will consider:

Causes

We don't completely understand what causes JIA. In fact, that's what ‘idiopathic’ means.

What we do know is that JIA is an autoimmune disease. The immune system is the body’s way of defending itself against injury, illness or bacteria.

The body can defend itself by causing inflammation or swelling. But when you have JIA, the body creates inflammation in a joint or joints when it doesn’t need to. This inflammation then causes stiffness and pain.

Is JIA genetic?

It's very rare to have two people in the same family with JIA, but we do know that genetic factors are involved. This is to do with the genes that are passed down from your parents.

JIA is thought to be due to a combination of genetic factors and trigger factors from the environment, for example the infections that the immune system has been in contact with.

There’s no evidence that a specific infection causes JIA, but an infection may trigger the immune system's response that then carries on and affects the joints.

Different types of JIA

There are several different types of juvenile idiopathic arthritis (JIA), some of which are milder than others.

You need to know which type you/your child has because this will help your doctor plan your treatment and give you advice.

Type of JIA	What is it?	What are the symptoms?	How will it affect me?	What else should I know
Oligoarticular JIA	The most common type – affects about two thirds of young people with arthritis. It's often mild.	Most commonly affects one or both knees. Most likely type to cause eye inflammation (chronic anterior uveitis) – you'll need regular eye checks.	Most likely type to go away leaving little or no joint damage	If you develop problems with five or more joints after six months, this is called extended oligoarthritis. This can cause joint damage. Your doctor may suggest early treatment with drugs like methotrexate to keep the damage to a minimum
Polyarticular JIA	The second most common type of JIA. It may come on suddenly or can steadily involve more joints over a period of months.	Painful swelling in fingers, toes, wrists, ankles, hips, knees, the neck and jaw. You may feel unwell and tired and occasionally develop a slight fever.	Symptoms may continue into adult life, but it can go into remission, where all the symptoms disappear.	A blood test will show whether a marker called rheumatoid factor is present in your blood.
Enthesitis-related JIA	Affects the places where the tendons attach to the bone (entheses), causing inflammation.	Often affects the joints of the leg and spine. Associated with a red painful eye condition (acute uveitis).	You may develop stiffness in your neck and lower back in your teens.	There may be a family history of ankylosing spondylitis or inflammatory bowel disease because of a particular genetic marker called HLA-B27.
Psoriatic arthritis	Psoriasis is a skin rash. A combination of joint pain and the rash is known as psoriatic arthritis	Usually affects fingers and toes but may affect other joints too. Joints may be affected before the psoriasis appears – your doctor may look closely at fingernails and toenails for early signs. Uveitis is fairly common but it's the painless type that doesn't look red.	It’s difficult to predict, but between 30-40% have ongoing disease into adulthood	Your doctor may ask if anyone else in your family has the condition.
Systemic-onset JIA	Your doctor may ask if anyone else in your family has the condition.	Enlarged glands in your neck, under your arms and around your groin. Your doctor may find your spleen and liver are enlarged, and, very occasionally, the covering of your heart is inflamed (pericarditis). In the first few weeks there may be no sign of swollen joints, and the diagnosis may be uncertain.	It can be difficult to predict how it'll affect you but usually the fever and rash will settle, although the arthritis may continue for several years before settling.	Lots of tests may be needed to confirm the diagnosis and this can be a worrying time.

 

How will JIA affect me/my child?

Many children who have JIA won't have any symptoms when they're adults, but it’s not possible to accurately predict this. In most cases, childhood arthritis has a good outcome.

In at least 30% of cases, however, arthritis can remain active into adult life. Some young adults with JIA have joint damage that limits their daily activities to some extent and a few may need joint replacements. Other problems can sometimes occur. Some people are physically smaller than average or have osteoporosis as a result of their arthritis and/or treatment with steroids.

A successful outcome in JIA requires many things, including:

• a positive approach
• an experienced team working alongside your GP
• a caring, helpful environment with support from family, friends and teachers.

You also need to know how to get help that you can understand, know who to approach and be confident enough to ask for support and advice.

Diagnosis

To make a diagnosis of JIA, a paediatric (young person’s) rheumatologist will examine the joints and ask questions.

There isn't a specific test for JIA, but your doctor will take blood tests and x-rays. They may also do other tests, including:

• ultrasound or MRI scans to try to see if there's arthritis and to rule out other conditions
• removing fluid from a joint (aspiration) to rule out joint infection
• bone marrow examination to rule out some rare conditions, especially if they think you/your child has systemic-onset JIA.

You/ your child will be diagnosed with JIA if:

• They have had arthritis for six weeks or more
• The symptoms started before  their 16th birthday
• The  doctor has ruled out other conditions that can cause arthritis.

Drugs

Drugs can’t cure arthritis, but they can control the symptoms and help to reduce the possibility of joint damage. An increasing number of medicines are now available.

Painkillers

These drugs help to control the pain of arthritis.

• Common painkillers include paracetamol, codeine or combinations e.g. co-codamol.
• They have to be taken regularly for maximum effect, which lasts hours not days.
• Side-effects include constipation, drowsiness and feeling a bit spaced-out.

Non-steroidal anti-inflammatory drugs (NSAIDs)

Non-steroidal anti-inflammatory drugs (NSAIDs) often help to reduce pain, stiffness and swelling.

Examples of the many NSAIDs include ibuprofen, piroxicam, naproxen and diclofenac. These have to be taken regularly to get maximum effect, which lasts hours not days.

Side-effects include indigestion and other stomach problems. The risk of this happening can be reduced by always taking them with food.

Disease-modifying anti-rheumatic drugs (DMARDs)

Disease-modifying anti-rheumatic drugs (DMARDs) dampen down inflammation and can reduce the joint damage caused by arthritis.

Methotrexate is the most commonly used DMARD in JIA. It can be given as a weekly dose by mouth or injection.

Side-effects of methotrexate are rare, but you’ll need regular blood tests to check for them.

DMARDs are slow to become effective and you may not notice any benefit for several months.

Biological therapies

Biological therapies is a name given to some newer drugs that have been available for about 10 years. Just like DMARDs, they slow down the progress of arthritis and reduce pain, swelling and stiffness.

Like DMARDs they work by suppressing the immune system, and they’re called biological therapies because they were developed from research into the biology of arthritis.

The main biological therapy used for JIA are etanercept, infliximab and adalimumab.

Steroids

These drugs control inflammation, pain and stiffness. They can be given as tablets, by injection into a joint or by a drip into a vein.

A common treatment for young people is a steroid injection into the affected joint.

• Injections are very effective for many months, are very well tolerated and cause very few side-effects.
• In younger children these injections will be done under general anaesthetic, but as you get older these may be done under sedation, with gas and air (entonox) or awake with a local anaesthetic. In adult clinics, joint injections are always given with a local anaesthetic when you’re awake.

Steroid tablets are used less for young people than steroid injections.

• Side-effects are more common with large doses and longer courses (over weeks and months).
• Short courses (for a few days or up to a week) or low doses tend to have few or no side-effects. Your doctor will try and limit side-effects by putting you on a low dose or short course.
• Your doctor will give you a steroid card which tells people you’re on steroids. Always carry this with you.
• Steroids should never be stopped suddenly (except if you’ve only been on them for under 2 weeks) as you can become very ill.

Eye drops

These will be used if you have eye inflammation. They’re used to reduce the inflammation, prevent the swollen iris from sticking to the lens and to reduce pressure inside the eye.

Some of the medicines used for the arthritis, such as methotrexate and the biological therapies, can be used to treat eye inflammation if the eye drops alone aren’t enough.