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Quick Facts

Juvenile Idiopathic Arthritis (JIA)

By

The Manual's Editorial Staff

Last full review/revision Apr 2021| Content last modified Apr 2021
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What is juvenile idiopathic arthritis (JIA)?

"Juvenile" refers to young people, usually those under the age of 16.

"Idiopathic" means that the cause of a disease or condition is not known.

"Arthritis" is when one or more of your joints are inflamed—they hurt, swell up, and turn red. There are many different types of arthritis.

  • Juvenile idiopathic arthritis is a rare kind of arthritis that children can get and that does not have a known cause

Juvenile idiopathic arthritis happens when a child's immune system attacks the joints. It's similar to rheumatoid arthritis in adults.

  • A few or many joints become painful and swollen

  • Other parts of the body may be affected

  • Symptoms may come and go

  • Doctors can tell if a child has JIA based on symptoms, x-rays, and blood tests

  • Treatments can include medicines and exercise

There are 6 forms of JIA, which vary by which joints are involved, how many joints are involved, and whether your child has other symptoms.

What causes JIA?

JIA is an autoimmune disease. The immune system is part of your body's defense system, which helps protect you from illness and infection. In an autoimmune disease, your immune system attacks parts of your own body by mistake—in JIA, a child's immune system attacks joints and sometimes other parts of the child's body. Doctors don't know exactly what causes your child's immune system to attack the joints.

What are the symptoms of JIA?

Symptoms may come and go. Some symptoms involve the joints. Other symptoms involve the rest of the body. Children with JIA do not all have the same symptoms. Some have a few mild symptoms, others have many severe symptoms.

Joint symptoms may involve a few or many joints, and include:

  • Pain and swelling

  • Joints feeling warm to the touch

  • Stiff joints, particularly in the morning

Symptoms that affect the rest of the body can include:

  • Fever

  • Blurry vision, and rarely painful, red eyes, and difficulty looking at bright lights

  • A patchy skin rash that does not itch

  • In the most severe form of JIA, swollen lymph nodes, spleen, and liver

  • Sometimes pain and irritation (inflammation) of the lining of the lungs and heart

What are the complications of JIA?

Children with severe JIA may not grow normally:

  • One arm or leg may be longer or shorter than the other

  • If JIA affects the jawbone, your child's chin may look too small

How can doctors tell if my child has JIA?

There is no specific test for JIA. The doctor will likely look at:

  • Your child's symptoms

  • Certain blood tests

Even if your child has no eye symptoms, an eye doctor should examine your child’s eyes to look for inflammation in parts of the eye.

How do doctors treat JIA?

There is no cure for JIA, but treatment can make children feel better and help them function normally. Some newer arthritis medicines may also help prevent complications, such as joint deformity and poor growth.

Doctors treat JIA with:

  • Medicines that reduce pain and swelling

  • Sometimes, shots of a medicine into a joint

  • Eye drops if your child’s eyes are affected

Doctors may also suggest:

  • Physical therapy and exercises

  • Sometimes, splints to keep your child’s joints straight

  • An eye examination several times a year

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