What is juvenile idiopathic arthritis?

Juvenile idiopathic arthritis (JIA), previously known as juvenile rheumatoid arthritis, is the most common type of arthritis in children.

Arthritis is a long-term condition characterized by:

  • stiffness
  • swelling
  • pain in the joints

An estimated 300,000 children in the United States have a form of arthritis. Some children have arthritis for just a few months, while others have arthritis for several years. In rare cases, the condition can last a lifetime.

The exact cause of JIA isn’t known. However, researchers believe it’s primarily an autoimmune disease. In people with autoimmune diseases, the immune system mistakenly attacks harmless cells as though they’re dangerous invaders.

Most cases of JIA are mild, but severe cases may result in complications, such as joint damage and chronic pain. Knowing the symptoms of JIA is important for getting treatment before the condition progresses.

Treatment usually consists of:

  • decreasing inflammation
  • managing pain
  • improving function
  • preventing joint damage

This can help ensure your child maintains an active, productive lifestyle.

The most common symptoms of JIA include:

JIA may affect one joint or multiple joints. In some cases, the condition can affect the entire body, causing a rash, fever, and swollen lymph nodes. This subtype is called systemic JIA (SJIA), and it occurs in about 10 percent of children with JIA.

There are six types of JIA:

  • Systemic JIA. This type of JIA affects the entire body, including the joints, skin, and internal organs.
  • Oligoarticular JIA. This type of JIA affects less than five joints. It occurs in about half of all children with arthritis.
  • Polyarticular JIA. This type of JIA affects five or more joints. The protein known as rheumatoid factor may or may not be present.
  • Juvenile psoriatic arthritis. This type of JIA affects the joints and occurs with psoriasis, which is why it’s referred to as juvenile psoriatic arthritis.
  • Enthesitis-related JIA. This type of JIA involves bone meeting the tendons and ligaments.
  • Undifferentiated arthritis. This type of JIA involves symptoms that may span two or more subtypes or not fit any of the other subtypes.

The more joints that are affected, usually the more severe the disease.

Your child’s healthcare provider may be able to diagnose JIA by performing a thorough physical exam and requesting a detailed medical history.

They may also order various diagnostic tests, such as:

  • C-reactive protein test. This test measures the amount of C-reactive protein (CRP) in the blood. CRP is a substance the liver produces in response to inflammation. Another test that detects inflammation, the sedimentation rate or erythrocyte sedimentation rate (ESR), may be performed as well.
  • Rheumatoid factor test. This test detects the presence of rheumatoid factor, an antibody produced by the immune system. The presence of this antibody often indicates a rheumatic disease.
  • Antinuclear antibody. Antinuclear antibody is an antibody to nucleic acid (DNA and RNA) that’s primarily located in the cell nucleus. It’s often created by the immune system in people with an autoimmune disease. An antinuclear antibody test can show whether the protein is present in the blood.
  • HLA-B27 test. This test detects a genetic marker that’s associated with enthesitis-related JIA.
  • X-ray or MRI scan. These imaging tests can be used to rule out other conditions that may be causing joint inflammation or pain, such as infections and fractures. Imaging can also reveal specific findings (signs) of subsets of inflammatory arthritis.

Various treatments can effectively manage and minimize the effects of JIA. Healthcare providers usually recommend a combination of treatments to relieve pain and swelling and to maintain movement and strength.

Medical treatment

Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil) and naproxen (Aleve), are often used to reduce inflammation and swelling in conjunction with other treatments. Using aspirin is rare because of potential adverse side effects in children.

Stronger medications are often prescribed, such as disease-modifying antirheumatic drugs (DMARDs) and biologics.

DMARDs work to modify the course of the disease, in this case suppressing the immune system to prevent it from attacking the joints.

Using DMARDs is recommended over NSAIDs alone. Your child’s healthcare provider may initially start treatment with DMARDs with or without NSAIDs before using biologics.

Some examples of DMARDs that are used to treat JIA include:

It’s important to note that methotrexate is currently recommended over other DMARDs.

Biologics work to directly target specific molecules or proteins that are involved in the disease process. Treatment with biologics may be combined with DMARD treatment.

Some examples of biologics that might be used to help decrease inflammation and joint damage include:

A steroid medication may be injected into the affected joint, particularly when symptoms interfere with the ability to perform daily activities. However, this isn’t recommended when a lot of joints are involved. In severe cases, surgery may be used to replace the joints altogether.

Lifestyle remedies

Exercising and maintaining a healthful diet are important for everyone, but they’re especially beneficial for children who have JIA. Having your child make the following lifestyle adjustments can help them cope with their symptoms more easily and reduce the risk for complications:

Eating well

Weight changes are common in children with JIA. Medications may increase or decrease their appetite, causing rapid weight gain or weight loss. In such cases, a healthful diet containing the right number of calories can help your child to maintain an appropriate body weight.

Speak with your healthcare provider about a meal plan if your child is gaining or losing too much weight as a result of JIA.

Exercising regularly

Exercising at least three times per week can strengthen muscles and improve joint flexibility, making it easier to cope with JIA in the long run. Low-impact exercises, such as swimming and walking, are usually best. However, it’s a good idea to speak with your child’s healthcare provider first.

Physical therapy

A physical therapist can teach your child the importance of sticking with an exercise routine and can even recommend exercises suited to their specific condition. The therapist may suggest certain exercises that can help build strength and restore flexibility in stiff, sore joints.

They will work with your primary healthcare provider to help prevent joint damage and bone/joint growth abnormalities.

Untreated JIA can lead to further complications. These include:

Children with mild to moderate JIA can usually recover without complications. However, JIA is a long-term condition that tends to cause occasional flare-ups. Your child can expect to have stiffness and pain in the joints during these outbreaks.

Once JIA becomes more advanced, the chances of going into remission are much lower. This is why early diagnosis and treatment are critical. Prompt treatment can prevent arthritis from becoming more severe and spreading to other joints.