It may begin with a swollen knuckle, a spiking fever, or an unexplainable rash. But no matter what symptoms appear, hearing the word "arthritis" in a diagnosis for your child can be unexpected and confusing.

Arthritis is an inflammation of the joints that is characterized by swelling, heat, and pain. 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 rare cases, it can last a lifetime.

The most prevalent form of juvenile arthritis is juvenile rheumatoid arthritis, or JRA. It affects approximately 50,000 children in the United States. JRA also called juvenile idiopathic arthritis (JIA) because it is very different from adult rheumatoid arthritis.

What Causes JRA?

It's not known exactly what causes JRA in kids. Research indicates that it is an autoimmune disease. In autoimmune diseases, white blood cells lose the ability to tell the difference between the body's own healthy cells and harmful invaders 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 JRA, you can help your child maintain an active, productive lifestyle.

Types of Juvenile Rheumatoid Arthritis

Typically, juvenile rheumatoid arthritis appears between the ages of 6 months and 16 years. The first signs often are joint pain or swelling and reddened 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.

The three major types of juvenile rheumatoid arthritis are:

1. Oligoarticular JRA, which affects four or fewer joints. Symptoms include pain, stiffness, or swelling in the joints. The knee and wrist joints are the most commonly affected. An inflammation of the iris (the colored area of the eye) may occur with or without active joint symptoms. This inflammation, called iridocyclitis, iritis, or uveitis, can be detected early by an ophthalmologist.
2. Polyarticular arthritis, 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 such as the knees, hips, ankles, feet, and neck. In addition, a low-grade fever may appear, as well as bumps or nodules on the body on areas subjected to pressure from sitting or leaning.
3. Systemic JRA, which 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 may also become enlarged. Eventually many of the body's joints are affected by swelling, pain, and stiffness.

Signs and Symptoms

The first signs of arthritis can be subtle or obvious. Signs may include limping or a sore wrist, finger, or knee. Joints may suddenly swell and remain enlarged. Stiffness in the neck, hips, or other joints can also occur. Rashes may suddenly appear and disappear, developing in one area and then another. High fevers that tend to spike in the evenings and suddenly disappear are characteristic of systemic juvenile rheumatoid arthritis.

Diagnosis

To diagnose JRA, the doctor will take a detailed medical history and conduct a thorough physical examination. The doctor may order X-rays or blood tests to exclude other conditions that can produce similar symptoms.

Other tests that may be done include:

• CBC (complete blood count), a common blood test used to evaluate all the basic cellular components of blood, including red blood cells, white blood cells, and platelets. Abnormalities in the numbers and appearances of these cells can be useful in the diagnosis of many medical conditions.
• Blood culture, a test to detect bacteria that cause infections in the bloodstream. This may be done to rule out infections.
• Bone marrow examination, a test that allows doctors to look at blood where it's formed (in the bone marrow) to rule out 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.
• A test for rheumatoid factor, an antibody produced in the blood of children with some forms of JRA. But it's much more commonly found in adults with rheumatoid arthritis.
• ANA (antinuclear antibody), a blood test to detect autoimmunity. It's also useful in predicting which children are likely to have eye disease with JRA.
• A bone scan, to detect changes in bone and joints to evaluate the causes of unexplained bone and joint pain.

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.

Doctors also may test for certain infections such as Lyme disease that may cause similar symptoms or occur along with the arthritis.

Treatments

In many cases, JRA may be treated with a combination of medication, physical therapy, and exercise. In specific situations, your child may require injection of corticosteroids into the joint or surgery. Your child's health care providers, including the primary care physician, rheumatologist, and physical therapist, will work together to develop the best method of treatment.

The goals of treatment are to relieve pain and inflammation, slow down or prevent the destruction of joints, and restore use and function of the joints to promote optimal growth, physical activity, and social and emotional development in your child.

Medications

For inflammation and pain, the doctor or pediatric rheumatologist may prescribe nonsteroidal anti-inflammatory drugs (NSAIDs), like ibuprofen (such as Advil or Motrin). These drugs may help reduce inflammation and pain by limiting the release of harmful chemicals from white blood cells.

Higher or lower dosages may be needed, depending upon your child's response to the medication. The doctor or rheumatologist should explain what the medication is meant to do and what side effects, if any, your child may experience. It's important for your child to continue taking the medication until the doctor says to stop.

If NSAIDs do not control inflammation of the joints, your doctor may prescribe other medications such as methotrexate. You can also ask for information about newer treatments that might be available.

Physical Therapy

An appropriate physical therapy program is essential in the management of any type of arthritis. A physical therapist will explain the importance of certain activities and recommend exercises suited to your child's specific condition. The therapist may recommend range-of-motion exercises to restore flexibility in stiff, sore joints and other exercises to help build strength and endurance.

Regular Exercise

When pain strikes, it's natural for your child to want to sit still. But it's important to maintain a regular exercise program. Muscles must be kept strong and healthy so they can help support and protect joints. Regular exercise also helps to maintain range of motion.

At home and at school, your child should maintain regular exercise and physical fitness programs. Safe activities include walking, swimming, and bicycling (especially on indoor stationary bikes). Always be certain your child warms up the muscles through stretching before exercising. Making exercise a family activity can increase the level of fun and enthusiasm.

Consult the doctor and physical therapist about sports restrictions. Some, especially impact sports, can be hazardous to weakened joints and bones. In addition, make sure your child eats a balanced diet that includes plenty of calcium to promote bone health.

Reviewed by: AnneMarie C. Brescia, MD
Date reviewed: June 2008