Juvenile Idiopathic Arthritis


Fact: Nearly 300,000 children in the United States have some sort of arthritis.

Arthritis is an inflammation of the joints, meaning that the joints get swollen, warm, and painful. Nearly 300,000 children in the United States have some sort of arthritis. Arthritis can be short-term — lasting for just a few weeks or months, then going away forever — or it can be chronic and last for months or years. In about half of cases, it can last a lifetime.

The most prevalent form of juvenile arthritis is juvenile idiopathic arthritis (JIA) (also known as juvenile rheumatoid arthritis, or JRA). It is very different from adult rheumatoid arthritis.
What Causes JIA?It's not known exactly what causes JIA in kids. Research indicates that it is an autoimmune disease. In autoimmune diseases, white blood cells can't tell the difference between the body's own healthy cells and germs like bacteria and viruses. The immune system, which is supposed to protect the body from these harmful invaders, instead releases chemicals that can damage healthy tissues and cause inflammation and pain.

To effectively manage and minimize the effects of arthritis, an early and accurate diagnosis is essential. By understanding the symptoms and characteristics of each type of JIA, you can help your child maintain an active, productive lifestyle.
Types of JIAJIA usually appears in kids between 6 months and 16 years old. The first signs often are joint pain or swelling or warm joints. Many rheumatologists (doctors specializing in joint disorders) find that the greater the number of joints affected, the more severe the disease and the less likely that the symptoms will eventually go into total remission. Remission is a medical term for temporary or permanent recovery.

There are seven types of JIA:

  1. Systemic JIA. Affects the whole body. Symptoms include high fevers that often increase in the evenings and then may suddenly drop to normal. During the onset of fever, the child may feel very ill, appear pale, or develop a rash. The rash may suddenly disappear and then quickly appear again. The spleen and lymph nodes might become enlarged. Eventually many of the body's joints are affected by swelling, pain, and stiffness. Rashes may suddenly appear and disappear, developing in one area and then another. High fevers that tend to increase in the evenings and disappear are characteristic of systemic JIA
  2. Oligoarthritis. Affects four or fewer joints, often the knee or ankle. Symptoms include pain, stiffness, or swelling in the joints. The two types of oligoarthritis, persistent and extended, are determined by how many joints are ultimately involved. 
  3. Polyarticular arthritis, rheumatoid factor negative. About 1 in 4 kids and teens with JIA have polyarthritis, which affects more girls than boys. Symptoms include swelling or pain in five or more joints. The small joints of the hands are affected as well as the weight-bearing joints like the knees, hips, ankles, feet, and neck. A low-grade fever also might develop, as well as bumps or nodules in areas of the body subjected to pressure from sitting or leaning.
  4. Polyarticular arthritis, rheumatoid factor positive. This type of JIA behaves the most like adult rheumatoid arthritis, and kids who have it have a protein called rheumatoid factor (RF) or anti-cyclic citrullinated peptide (CCP antibody) in their blood. Kids with polarticular JIA are at a higher risk of joint damage with erosions than in the other forms of JIA.
  5. Psoriatic arthritis. Kids with this also have the psoriasis rash (a scaly red rash that can start behind the ears, on the eyelids, elbows, knees, or scalp) themselves or a close relative with psoriasis. Their fingernails and toenails might be affected by the condition.
  6. Enthesitis-related arthritis. This type of arthritis often affects the legs and spine. Kids also might have inflammation at the entheses – areas where tendons join bones (where the Achilles tendon attaches to the back of the heel). Enthesitis-related arthritis includes a special group call juvenile ankylosing spondylitis (where joints of the low back are inflamed) and arthritis associated with inflammatory bowel disease (Crohn's disease and ulcerative colitis).
  7. Undifferentiated arthritis. Arthritis that doesn't fit into any of the above categories or fits into more than one of the categories.

Symptoms
The most common signs and symptoms of juvenile idiopathic arthritis are:

  • Pain. While your child might not complain of joint pain, you may notice that he or she limps — especially first thing in the morning or after a nap.
  • Swelling. Joint swelling is common but is often first noticed in larger joints such as the knee.
  • Stiffness. You might notice that your child appears clumsier than usual, particularly in the morning or after naps.
  • Fever, swollen lymph nodes and rash. In some cases, high fever, swollen lymph nodes or a rash on the trunk may occur — which is usually worse in the evenings.

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.

What causes JIA?
Malfunctioning of the immune system in JIA targets the lining of the joint, known as the synovial membrane. This causes inflammation. When the inflammation is untreated, joint damage may occur.

It is not known what causes the immune system to malfunction in JIA. In rare cases (such as in psoriatic arthritis or enthesitis-related arthritis) a parent has the same form of arthritis. Dietary and emotional factors do not appear to play a role in the development of JIA.

Because the causes of JIA are unknown, no one knows how to prevent these conditions.

Complications
Several serious complications can result from juvenile idiopathic arthritis. But keeping a careful watch on your child's condition and seeking appropriate medical attention can greatly reduce the risk of these complications:

  • Eye problems. Some forms can cause eye inflammation (uveitis). If this condition is left untreated, it may result in cataracts, glaucoma and even blindness.
    Eye inflammation frequently occurs without symptoms, so it's important for children with this condition to be examined regularly by an ophthalmologist.
  • Growth problems. Juvenile idiopathic arthritis can interfere with your child's growth and bone development. Some medications used for treatment, mainly corticosteroids, also can inhibit growth.


Diagnosis
To diagnose JIA, the doctor will take ask you questions about your child’s symptoms, find out whether other family members have had similar problems, and do a thorough physical examination. The doctor may order X-rays or blood tests to rule out other conditions or infections, such as Lyme disease, that may cause similar symptoms or occur along with the arthritis.

Other tests may include:

  • CBC (complete blood count), a common blood test that checks all the basic cell types in blood, including red blood cells, white blood cells, and platelets. Knowing the amount and appearance of each cell type in a person’s blood can help doctors identify many medical conditions.
  • Blood culture, a test to detect bacteria that cause infections in the bloodstream.
  • Bone marrow biopsy, a test that allows doctors to look at blood where it's formed (in the bone marrow) to look for conditions such as leukemia.
  • Erythrocyte sedimentation rate, which checks how rapidly red blood cells settle to the bottom of a test tube. This rate often increases in people when inflammation is occurring in the body.
  • C-reactive protein (CRP) is a protein that the liver releases into the blood at the start of infection or inflammation; this level can rise if a person is having an arthritis flare-up.
  • A test for rheumatoid factor (RF) and cyclic citrullinated peptide antibody (CCP), substances made in the blood of children with some forms of JIA. But it's found more often in adults with rheumatoid arthritis.
  • ANA (antinuclear antibody), a blood test to detect autoimmune diseases. It's also useful in predicting which kids are likely to have eye disease with JIA.
  • X-rays of the affected joints, and sometimes an MRI, to detect changes in bone and joints to evaluate the causes of unexplained bone and joint pain. In some cases, doctors may do a test called a bone scan. 

In some cases, the doctor may want an orthopedic surgeon to examine your child's joints and take samples of joint fluid or synovium (the lining of the joints) for examination and testing.

Treatment
Treatment for juvenile idiopathic arthritis focuses on helping your child maintain a normal level of physical and social activity. To accomplish this, doctors may use a combination of strategies to relieve pain and swelling, maintain full movement and strength, and prevent complications.

Medications
The medications used to help children with juvenile idiopathic arthritis are chosen to decrease pain, improve function and minimize potential joint damage.


Typical medications include:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs). These medications, such as ibuprofen (Advil, Motrin IB, others) and naproxen sodium (Aleve), reduce pain and swelling. Side effects include stomach upset and liver problems.
  • Disease-modifying antirheumatic drugs (DMARDs). Doctors use these medications when NSAIDs alone fail to relieve symptoms of joint pain and swelling or if there is a high risk of damage in the future.
    DMARDs may be taken in combination with NSAIDs and are used to slow the progress of juvenile idiopathic arthritis. The most commonly used DMARD for children is methotrexate (Trexall). Side effects of methotrexate may include nausea and liver problems.
  • Biologic agents. Also known as biologic response modifiers, this newer class of drugs includes tumor necrosis factor (TNF) blockers, such as etanercept (Enbrel) and adalimumab (Humira). These medications can help reduce systemic inflammation and prevent joint damage.
    Other biologic agents work to suppress the immune system, including abatacept (Orencia), rituximab (Rituxan), anakinra (Kineret) and tocilizumab (Actemra).
  • Corticosteroids. Medications such as prednisone may be used to control symptoms until another medication takes effect. They are also used to treat inflammation when it is not in the joints, such as inflammation of the sac around the heart (pericarditis).
    These drugs can interfere with normal growth and increase susceptibility to infection, so they generally should be used for the shortest possible duration.


Therapies
Your doctor may recommend that your child work with a physical therapist to help keep joints flexible and maintain range of motion and muscle tone.

A physical therapist or an occupational therapist may make additional recommendations regarding the best exercise and protective equipment for your child.

A physical or occupational therapist may also recommend that your child make use of joint supports or splints to help protect joints and keep them in a good functional position.


​Surgery
In very severe cases, surgery may be needed to improve the position of a joint.

Want to learn more?
The following organizations and/or websites offer additional information and education about 
Juvenile Idiopathic Arthritis. They are listed in alphabetical order without any preference or prejudice.  Listing these organizations is not a recommendation or referral in any regard for seeking treatment or consultation or support for treatment.   

American College of Rheumatology
Arthritis Foundation
Genetics Home Reference
Kids Health
Mayo Clinic
WebMD



Information on this page taken from:

American College of Rheumatology
Kids Health
Mayo Clinic