About Juvenile Idiopathic Arthritis

Juvenile Idiopathic Arthritis (JIA) in Ireland

• Over a thousand Irish children are battling Arthritis.
• 56 NEW cases of Juvenile Arthritis are diagnosed in Ireland every year.

Currently in Ireland there are over a thousand children under the age of 16 with Juvenile Idiopathic Arthritis (JIA). JIA differs from Adult Onset Arthritis in that it is caused by the immune system which starts attacking the body’s own joints. The cause of JIA is multifactorial and includes genetic predisposition and environmental factors.

Because children are growing, any extended period of inflammation can effect their joint formation. Therefore early and aggressive treatment of Juvenile Arthritis results in the best outcomes for children.
Joints can become painful and swollen for a number of reasons and in most cases it is possible to quickly identify a cause. This may be injury, infection in the joint or surrounding area or it may be a reaction to some other infection such as a streptococcal throat infection or gastroenteritis.
If there is no obvious cause and the condition persists then JIA must be considered as a cause. There is no diagnostic test for JIA. It is diagnosed based on the history of the patient, some specific tests and clinical observation. When JIA is suspected it is typical that tests are carried out for other conditions in order to exclude them as the cause of the symptoms.
In JIA no trigger is identified but the inflammation persists beyond 6 weeks. The child may complain of pain in the affected joint / joints, which become stiff on waking up in the morning and after periods of inactivity. They joints are often swollen and warmer than the surrounding area.
JIA is split into different types depending on the number of joints affected, the way it initially presents itself and the results of some specific tests. These groups are explained in the linked articles. One of these types, Systemic Onset JIA can be difficult to diagnose initially as it usually starts with a fever and rash resembling a viral infection. The arthritis, usually involving small and large joints, may not develop for several weeks.
Inflammation of the internal lining of the eye (uveitis) is a potentially serious complication of JIA. Regular eye screening is essential to detect its presence at an early stage, as patients remain symptom free until the eye suffers significant and sometimes irreversible damage.

More information about Uveitis 

The treatment of JIA tends to be in two phases. The first aims to get the patient feeling better quickly and will typically involve aggressive tactics such as high doses of steroids. The second phase sees the shift to maintenance of wellbeing and may involve dropping the levels of some drugs and introducing others. We have articles about most of the medicines used in other areas of the site. Although doctors will have set strategies to deal with JIA these should be seen as starting points from which the treatment will be adjusted to suit each patient taking many factors in to account.
At present there is no cure for JIA. Modern medication and on-going management by paediatric rheumatology specialists mean that in most cases there is good disease control and long term joint and eye damage can be prevented in most patients.

More detailed medical description of JIA 

Information with thanks to Scottish Network for Arthritis in Children (SNAC) 

eye drawing

What does Uveitis mean?

The term uveitis means there is inflammation within the eye. The uvea is the lining of the eye and the ending itis means inflammation. It may also be described as iritis.
The diagram shows the different parts of the eye. The dotted area is the uvea. Uveitis can affect different areas in the eye so you may hear it said the uveitis is anterior (at the front), intermediate (in the middle) or posterior (at the back) of the eye.

Why has my child developed Uveitis?

Most of the children who develop uveitis have arthritis. Some children have other medical problems, like inflammatory bowel disease, Behcet’s syndrome or sarcoid. For some children, even after tests, no underlying cause is found, when it is called idiopathic uveitis. The treatment is very similar whatever the cause.

Are there different types of Uveitis?

Yes, chronic, intermediate and acute uveitis all occur in children. The symptoms tend to be different. Chronic uveitis tends to develop gradually and the eyes do not look red and are not painful. This is the type most commonly associated with arthritis. Acute uveitis can develop quickly over a period of days, and cause pain and redness of the eye.

Can uveitis cause damage to the eye?

Ongoing inflammation in the eye eventually damages the delicate structures of the eye. The main problems it can cause are cataract, which is clouding of the lens of the eye, high pressure in the eye, called glaucoma, and the inflammation can lead to reduced vision.

How do we treat Uveitis?

Whatever the type of uveitis the aim of treatment is to control the inflammation in the eye.
Uveitis is treated with eye drops or medicines. Generally, mild forms of uveitis are treated with eye drops alone until the inflammation settles down. The standard type of eye drop which is used is a steroid eye drop. For a few patients where the inflammation settles down quickly, and stays away, this may be all the treatment that is needed. However additional treatment is considered if steroid eye drops do not settle down the inflammation promptly, or if the inflammation returns when the drops are reduced.
The aim of treatment for uveitis is to control the inflammation within the eye without the need for ongoing steroid eye drops. Long term the steroid eye drops can damage the eye themselves.
A number of different medicines can reduce inflammation in the body by damping down the immune system. The medicines may be given as liquids, tablets or by injection. These can be very good at treating uveitis and your Doctor or Nurse will discuss these with you if your child needs them. Paediatric Rheumatology Doctors and Rheumatology Nurse Specialists frequently work with the ophthalmologists when these medicines are used, and will give you information about the use of these treatments.

How do you know if there is still inflammation in the eye?

Uveitis may have periods of good control, and periods when the inflammation returns. In many children, particularly the youngest, the eye does not go red, painful, or have any symptoms at all. So regular eye checks are an important part of the care your child. In some children uveitis can cause redness and pain; always ask for advice if your child is complaining of sore eyes, or their eyes become very sensitive to light.

What tests and checks are done?

First we will measure your child’s vision. This is usually done by reading letters on a letter chart. In young children we use pictures. Then we examine the eyes using a microscope. This is called a slit lamp because the little beam of light used to examine the eyes has a slit shape. This examination can be tricky in young children as the head has to be kept still. You can help with this part of the examination by gently holding your child in a comfortable position beside the microscope.
When your child comes to clinic we may need to put in some eye drops to make the pupils large. The drops are slightly stingy. They usually take about half an hour to work and they can last for up to 12 hours. During this time your child’s vision can be a little blurry. This allows us to get a better look inside the eye. We do this so we can look for any inflammation deeper inside the eye.
Remember inflammation causes damage to the eye if left untreated so regular checks of your child’s eyes, and treatment of the inflammation when it is present are the best way to protect the eye.

What do all these medical words mean?

Arthritis and uveitis both end in itis. Itis means inflammation, arth means joint, so the word arthritis just means inflamed joints, and uveitis means inflammation of the bit of the eye medically called the uvea, which is the inside lining of the eye.
The medical word idiopathic means the cause is unknown. Many medical conditions are idiopathic. We know how to treat many conditions even when their cause is unknown.
Chronic means going on over time, acute means suddenly. These words describe the way the inflammation behaves in different types of uveitis.
Anterior means at the front, intermediate means in the middle and posterior means back. These terms describe where the inflammation is found in the eye.
Information with thanks to Scottish Network for Arthritis in Children (SNAC)

Juvenile Idiopathic Arthritis (JIA) is a chronic inflammatory disorder of the body joints affecting about 1⁄1000 children and adolescents under 16 years of age. There are several causes of joint inflammation such as an injury or infection of the joint itself (septic arthritis) or more frequently infection somewhere else in the body (reactive arthritis) such as a streptococcal throat infection or gastroenteritis. These trigger the release of hormones such as TNF and cytokines within the joint which induce and perpetuate the inflammation. There is an increased blood flow though the lining of the joint (synovium) which becomes swollen and produces excess joint fluid. Reactive arthritis usually resolves within a month from onset.
In JIA no trigger is identified but the inflammation persists beyond 6 weeks. The child complains of pain in the affected joint ⁄ joints, which become stiff on waking up in the morning and after periods of inactivity. They are swollen and warm and fluid may be elicited in the larger joints (ex: knee). The arthritis may affect a few joints (oligoarthritis) or many joints (polyarthritis). It may spread to other joints (extended oligoarthritis).
95% children are rheumatoid factor (RF) negative. The other 5% are RF positive and have a more aggressive disease course similar to that in adult rheumatoid arthritis.
Arthritis may be the presenting manifestation in psoriasis and in enthesitis related arthritis (ERA), which is the paediatric equivalent of ankylosing spondylitis in adults.
Systemic Onset JIA can be difficult to diagnose initially as it presents with fever and rash resembling a viral infection. The arthritis, usually involving small and large joints, may present weeks later.
Arthritis is also seen in children with a variety of conditions including Down’s syndrome and inflammatory bowel disease. The diagnosis of JIA is made after a detailed history and examination. There is no diagnostic test. Some investigations, such as blood picture and xrays are done mainly to exclude other causes of arthritis. Other investigations, such as the inflammatory markers ESR and CRP, are useful in monitoring the disease course. The autoantibodies ANA ( anti-nuclear antibody) and RF (rheumatoid factor) are helpful in giving a prognosis on the severity and duration of JIA. Patients with ERA are likely to have an HLA B27 positive tissue type. Ultrasound and MRI scans give useful information on the extent of inflammation in the joints.
Inflammation of the internal lining of the eye (uveitis) is a potentially serious complication of JIA. It is more common in female patients especially those who are ANA positive and in patients with oligoarthritis. Regular eye screening is essential to detect its presence at an early stage, as patients remain symptom free until the eye suffers significant and sometimes irreversible damage.
The treatment of JIA aims at the rapid suppression of inflammation in the joints, best achieved with intra-articular steroid injections, together with the suppression of the underlying autoimmune process by the administration of immunosuppressants such as methotrexate. The biological agents Etanercept, Infliximab and Adalimumabblock TNF, the main hormone inducing synovial inflammation.
Physiotherapy and hydrotherapy are useful aids in helping the child with JIA by building up the muscles and keeping the affected joint⁄s supple. Occupational therapists give useful advice on how to cope with any restrictions imposed on body movements by the arthritis. The prognosis and severity of arthritis varies with the JIA subtype. In general the more the number of joints involved the longer is the duration of JIA and the greater is the chance of arthritis continuing beyond puberty; but the smaller the chance of developing uveitis.
Although a cure is not available, modern advances in therapy allow good disease control and prevent long term joint and eye damage in most patients.
Dr P Galea, Consultant Paediatric Rheumatologist, Yorkhill Hospital, Glasgow 7th May 2010
Information with thanks to Scottish Network for Arthritis in Children (SNAC)