What Is Systemic Juvenile Idiopathic Arthritis?

Systemic juvenile idiopathic arthritis is a type of juvenile idiopathic arthritis (JIA). JIA is a group of disorders that causes arthritis (stiff, swollen, painful joints) in children.

Children with systemic juvenile idiopathic arthritis (systemic JIA) have periods of arthritis along with a fever and rash. They also may have swollen glands and problems with the heart, lungs, and blood.

Treatments can help with symptoms, so children can live a full and active life. The symptoms can go away for a time (called remission). In some kids, the condition goes away permanently.

What Are the Signs & Symptoms of Systemic Juvenile Idiopathic Arthritis?

Children with systemic JIA have:

• arthritis in one or more joints (usually the wrists, knees, and ankles) for more than 6 weeks
• high fevers that usually come and go for more than 2 weeks
• a rash

They may also have:

• anemia (low red blood cell count)
• an enlarged liver, spleen, or lymph nodes
• joint damage
• inflammation of the lining of the heart or lungs

What Causes Systemic Juvenile Idiopathic Arthritis?

All types of JIA happen when the immune system, which normally attacks germs, mistakenly attacks the joints. This causes inflammation (swelling and irritation) in the joints and other problems.

Systemic JIA can start anytime in kids 1 to 16 years old. Most cases start when a child is around 2 years old. The condition affects boys and girls equally.

Doctors don’t know exactly why kids and teens get JIA. “Idiopathic” means “from an unknown cause.” It can run in families but often does not. It’s likely due to a combination of:

• genetic (inherited) causes
• the way the immune system responds to infection and illness
• a trigger, such as an infection

How Is Systemic Juvenile Idiopathic Arthritis Diagnosed?

To diagnose systemic JIA, doctors:

• ask about symptoms
• do an exam
• ask whether other family members have had similar problems
• do X-rays or other imaging studies to look inside the joints
• order blood tests to check for:
  • anemia or other blood problems
  • inflammation in the body
  • markers for some types of arthritis or autoimmune illnesses

Sometimes, an orthopedic surgeon (bone doctor) takes samples of joint fluid or synovium (the lining of the joints). The sample is sent to a lab for testing.

How Is Systemic Juvenile Idiopathic Arthritis Treated?

Systemic JIA is treated by a care team that includes:

• a rheumatologist (for problems with joints and connective tissue)
• a primary care doctor (such as a pediatrician or family medicine doctor)
• a physical therapist

Treatment goals are to ease pain and inflammation, improve strength and flexibility, and prevent joint damage. Treatment usually includes medicines to ease inflammation and physical therapy.

Sometimes surgery is needed for damaged joints.

What Other Problems Can Happen?

Rarely, kids with JIA can get a life-threatening problem called macrophage activation syndrome. It happens when the immune system becomes too active and damages some of the body’s organs. It can lead to severe diarrhea, bleeding, hearing loss, confusion, and seizures.

Macrophage activation syndrome needs treatment right away:

• Go to the emergency room if your child has severe diarrhea, bleeding, confusion, or seizures, or seems very sleepy.

How Can Parents Help?

Systemic JIA usually is a lifelong disease, but treatments can help ease pain, keep kids active, and prevent long-term joint damage. To help your child:

• Be sure your child takes all medicines exactly as directed.
• Work with the physical therapist to develop a regular exercise program. This will help keep your child’s muscles strong and flexible. 
• Learn all you can about systemic JIA with your child. Your care team is a great resource. You also can find information and support online at:
  • The Arthritis Foundation