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 may be minimal.

When to see a doctor

Take your child to the doctor if he or she has joint pain, swelling or stiffness for more than a week — especially if he or she also has a fever.

Juvenile idiopathic arthritis occurs when the body's immune system attacks its own cells and tissues. It's not known why this happens, but both heredity and environment seem to play a role.

Some forms of juvenile idiopathic arthritis are more common in girls.

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. 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 of juvenile idiopathic arthritis can be difficult because joint pain can be caused by many different types of problems. No single test can confirm a diagnosis, but tests can help rule out some other conditions that produce similar signs and symptoms.

Blood tests

Some of the most common blood tests for suspected cases include:

• Erythrocyte sedimentation rate (ESR). The sedimentation rate is the speed at which your red blood cells settle to the bottom of a tube of blood. An elevated rate can indicate inflammation. Measuring the ESR is primarily used to determine the degree of inflammation.
• C-reactive protein. This blood test also measures levels of general inflammation in the body but on a different scale than the ESR.
• Antinuclear antibody. Antinuclear antibodies are proteins commonly produced by the immune systems of people with certain autoimmune diseases, including arthritis. They are a marker for an increased chance of eye inflammation.
• Rheumatoid factor. This antibody is occasionally found in the blood of children who have juvenile idiopathic arthritis and may mean there's a higher risk of damage from arthritis.
• Cyclic citrullinated peptide (CCP). Like the rheumatoid factor, the CCP is another antibody that may be found in the blood of children with juvenile idiopathic arthritis and may indicate a higher risk of damage.

In many children with juvenile idiopathic arthritis, no significant abnormality will be found in these blood tests.

Imaging scans

X-rays or magnetic resonance imaging may be taken to exclude other conditions, such as fractures, tumors, infection or congenital defects.

Imaging may also be used from time to time after the diagnosis to monitor bone development and to detect joint damage.

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, others) and naproxen sodium (Aleve), reduce pain and swelling. Side effects include stomach upset and, much less often, kidney 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, Xatmep, others). Side effects of methotrexate may include nausea, low blood counts, liver problems and a mild increased risk of infection.

• Biologic agents. Also known as biologic response modifiers, this newer class of drugs includes tumor necrosis factor (TNF) blockers, such as etanercept (Enbrel, Erelzi, Eticovo), adalimumab (Humira), golimumab (Simponi) and infliximab (Remicade, Inflectra, others). These medications can help reduce systemic inflammation and prevent joint damage. They may be used with DMARDs and other medications.

  Other biologic agents work to suppress the immune system in slightly different ways, including abatacept (Orencia), rituximab (Rituxan, Truxima, Ruxience), anakinra (Kineret) and tocilizumab (Actemra). All biologics can increase the risk of infection.

• 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.

  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 joint function.

Caregivers can help children learn self-care techniques that help limit the effects of juvenile idiopathic arthritis. Techniques include:

• Getting regular exercise. Exercise is important because it promotes both muscle strength and joint flexibility. Swimming is an excellent choice because it places minimal stress on joints.
• Applying cold or heat. Stiffness affects many children with juvenile idiopathic arthritis, particularly in the morning. Some children respond well to cold packs, particularly after activity. However, most children prefer warmth, such as a hot pack or a hot bath or shower, especially in the morning.

• Eating well. Some children with arthritis have poor appetites. Others may gain excess weight due to medications or physical inactivity. A healthy diet can help maintain an appropriate body weight.

  Adequate calcium in the diet is important because children with juvenile idiopathic arthritis are at risk of developing weak bones due to the disease, the use of corticosteroids, and decreased physical activity and weight bearing.

Family members can play critical roles in helping children cope with their condition. As a parent, you may want to try the following:

• Treat your child like other children in your family as much as possible.
• Allow your child to express anger about having juvenile idiopathic arthritis. Explain that the disease isn't caused by anything he or she did.
• Encourage your child to participate in physical activities, keeping in mind the recommendations of your child's doctor and physical therapist.
• Discuss your child's condition and the issues surrounding it with teachers and administrators at his or her school.

If your pediatrician or family doctor suspects that your child has juvenile idiopathic arthritis, he or she may refer you to a doctor who specializes in arthritis (rheumatologist) to confirm the diagnosis and explore treatment.

What you can do

Before the appointment, you might want to write a list that includes:

• Detailed descriptions of your child's symptoms
• Information about medical problems your child has had in the past
• Information about the medical problems that tend to run in your family
• All the medications and dietary supplements your child takes
• Your child's immunization status
• Questions you want to ask the doctor

What to expect from your doctor

Your doctor may ask some of the following questions:

• Which joints appear to be affected?
• When did the symptoms begin? Do they seem to come and go?
• Does anything make the symptoms better or worse?
• Is the joint stiffness worse after a period of rest?