Spotlight on juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is chronic inflammatory arthritis developing in children under the age of 16 years. Previously called juvenile rheumatoid arthritis (JRA), juvenile idiopathic arthritis strikes up to three in 1000 children and is one of the most common chronic diseases among children.

Autoimmune diseases generally occur when the body's immune system begins to malfunction and attack healthy tissue in various parts of the body, causing inflammation and damage. In JIA, joints are attacked by inflammation and become stiff, painful, and swollen. Some children with JIA develop inflammation involving their eyes as well; in some severe subtypes of JIA, organs such as the heart or lungs can be involved.

Overall, JIA affects girls slightly more often than boys. JIA can affect children of any age, from infancy to 16 years. While it has no known cure, there are effective treatments for JIA which can often lead to remission and prevent permanent joint damage and disability.

Diagnosis of juvenile idiopathic arthritis

There are seven subtypes of juvenile idiopathic arthritis, defined by the ILAR international criteria:
  • Oligoarticular-the most common form of the disease. About half of children with juvenile idiopathic arthritis are diagnosed with the oligoarticular form. Generally, one to four joints are affected. Most common joints include knees, ankles, or wrist. Up to 20% of children diagnosed with the oligoarticular form of juvenile idiopathic arthritis will develop uveitis (inflammation in the eyes).
  • Extended oligoarticular-approximately 30% of children whose JIA starts in fewer than 4 joints will develop arthritis in many joints at some point in their disease; this is called 'extended'.
  • Polyarticular (rheumatoid factor positive and rheumatoid factor negative)-JIA affecting five or more joints. Any joint can be involved, and usually the arthritis is symmetric (the same on both sides of the body). Children who have a positive rheumatoid factor (RF) have a more persistent and severe type of polyarticular disease.
  • Enthesitis related arthritis-this form of JIA occurs more commonly in school aged or older children, boys more than girls. Arthritis can affect large joints such as the hip, knee, ankles, as well as the back and neck. Some of these children have inflammation of ligament and tendon attachments, called enthesitis. A small percentage of these children go on to develop ankylosing spondylitis.
  • Psoriatic arthritis-children may have arthritis and psoriasis, or arthritis and a strong family history of psoriasis. This form of arthritis can affect any joint.
  • Systemic onset-the most severe form of the disease, affecting about 10% of children diagnosed with juvenile idiopathic arthritis. Children with systemic onset JIA present quite ill with high fevers, rash, and inflammation of organs in addition to inflammation in the joints.

The most common complaint of children at the time they develop juvenile idiopathic arthritis is joint pain, accompanied by swelling or stiffness. Other warning signs which may be present at the onset of disease include:
  • Change in ability to keep up with normal activities, such as sports or school work because of physical joint pain.
  • Irritability, especially in a young child who is in pain
  • Refusal to walk, limping, or a child who knows how to walk may return to crawling

Because the symptoms of juvenile idiopathic arthritis at the outset of the disease are similar to many other diseases, such as infections, cancer, other bone problems, and other inflammatory illnesses, doctors must exclude these other possibilities before a diagnosis of juvenile idiopathic arthritis is possible.

In addition to a full physical examination and medical history, doctors may order several different types of tests in order to exclude other possibilities and confirm a tentative diagnosis of juvenile idiopathic arthritis. It is important to recognize, however, that there are no blood tests which can confirm the diagnosis of JIA.

Treatment for juvenile idiopathic arthritis

While there is no cure for juvenile idiopathic arthritis, treatment advances are allowing more children to live normal lives. Medications have been developed that can reduce pain and even slow or stop the inflammation that causes devastating joint damage. As well, physical and occupational therapy can help to allow children to participate in normal activities, and to prevent long-term disability.

Once a diagnosis of juvenile idiopathic arthritis is suspected, the child should be referred to a pediatric rheumatology team, a group which includes a pediatric rheumatologist, nurses, pediatric physiotherapist, pediatric occupational therapist, and social worker. These specialists will work together to confirm a diagnosis, design the best treatment plan for the child, and work together with the parents and child to carry out the treatments to maintain joint health. A pediatric rheumatologist is a doctor with specialized training in pediatrics, and then pediatric rheumatology.

Children with JIA may need to see other pediatric specialists; for example, they should have regular full eye exams from an ophthalmologist (eye specialist) to check for uveitis (eye inflammation).

A well-rounded treatment plan for juvenile idiopathic arthritis includes medication, education, physiotherapy and occupational therapy, and a healthy diet.

A variety of medications commonly used to treat juvenile idiopathic arthritis.
  • The "first line" treatments are non-steroidal anti-inflammatory drugs (NSAIDs). Naproxen (Naprosyn®) is the most common NSAID used for treating JIA, but others are used as well.
  • The "second line" treatments are called disease-modifying anti-rheumatic drugs (DMARDs). Examples of these include hydroxychloroquine (Plaquenil®), sulfasalazine (Azulfadine®), leflunomide (Arava®) and most commonly methotrexate (Rheumatrex®). DMARDs work to slow or halt the inflammation and disease progression that can cause devastating joint damage and disability. Many children have an excellent response to one, or a combination, of these medications.
  • For some children, traditional DMARDs alone will not be enough to control their disease. In these cases, a biologic response modifier may be used. Biologics are the newest, most powerful medications to treat inflammatory arthritis. Examples of these medications are etanercept (Enbrel®) and infliximab (Remicade®). Newer biologic medications are currently being studied in children with JIA. Biologics are often used in combination with traditional DMARDs.

Many parents of children with juvenile idiopathic arthritis note that giving medications is one of the most difficult parts of coping with the disease. This is why education is such a critical part of a treatment plan for juvenile idiopathic arthritis. Like many inflammatory arthritis diseases, early aggressive treatment is vitally important. Parents who have received all of the necessary information are much more likely to be able to help create and implement a well-rounded, effective treatment plan. It is important to remember that children who are treated quickly and effectively have the very best chance of recovering fully and maintaining joint health. The pediatric rheumatology team, especially the nurse, is usually a great support for parents as they learn about how best to treat their child.

Physiotherapy and occupational therapy are very important treatment plan components for every child with JIA. The physiotherapist and occupational therapist will work on regaining range of motion in stiff joints, providing techniques for pain relief, splinting when required, and once the disease is controlled, an exercise plan.

Exercise is a key component of a well-rounded treatment plan for juvenile idiopathic arthritis, and should be carefully balanced with adequate rest. Exercise can help maintain joint health — keeping them strong and flexible — and rest can help relax joint. Children with JIA are encouraged to participate in usual activities, such as sports and PE, to the best of their abilities. Many children with JIA are outstanding athletes!

Children and teens with JIA are encouraged to return to their regular physical activities as soon as they are able. As much as possible, children with juvenile idiopathic arthritis should continue to participate in normal activities of childhood, like attending school. It is rare that a child or teen with JIA should be missing school due to their arthritis.

The outcome for children with JIA has improved over the past years, especially if the disease is recognized and treated effectively in the early stages of the disease process. However, despite these advances, most children with JIA will continue to have some form of arthritis into adulthood.