What is Juvenile Idiopathic Arthritis?

Juvenile Idiopathic Arthritis (JIA) is an autoimmune disease that can cause inflammation, swelling, stiffness and pain in the joints and is the most common type of arthritis in children under 16 years.

What you should know about JIA

  • Juvenile Idiopathic Arthritis can affect one joint or many
  • There are several different subtypes of Juvenile Idiopathic Arthritis, but the main ones are systemic, oligoarticular and polyarticular
  • Which type your child has depends on symptoms, the number of joints affected, and if a fever and rashes are prominent features
  • Like other forms of arthritis, Juvenile Idiopathic Arthritis is characterized by times when symptoms flare up and times when symptoms disappear.

The symptoms of JIA

The most common signs and symptoms of Juvenile Idiopathic Arthritis are:

  • Pain and joint swelling
  • Stiffness – particularly in the morning or after naps
  • Fever, swollen lymph nodes or rash.

What causes JIA?

The word “idiopathic” means “the cause is unknown.” But even though scientists and doctors don’t know the exact cause of JIA, they do know that it’s likely caused by a combination of factors:

  • Genetics
  • Environment
  • Immune system

Some children with JIA produce too much of certain proteins, including TNF. When too much TNF is produced, inflammation can result. This can contribute to symptoms of JIA such as joint pain, swelling, and stiffness.

Diagnosing JIA: It’s not so easy

There isn’t one specific test that can diagnose JIA, but doctors use a combination of the following methods to make a diagnosis:

  • Medical history
  • Physical exam
  • X-rays or magnetic resonance imaging (MRI)
  • Blood tests
  • Process of elimination—ruling out other conditions that can have similar symptoms

Getting the proper diagnosis and treatment is important. It can reduce the signs and symptoms of Juvenile Idiopathic Arthritis.