Juvenile Arthritis

The typical arthritis sufferer has at least a few gray hairs, a wrinkle here and there, and joints that have started to wear out after decades of use. But not every person with arthritis fits that profile. Some forms of arthritis can strike children or even infants. Arthritis may seem like a cruel fate for a young person, but many children cope admirably with their disease. With treatment and support, they have a good chance of staying active and happy.

By far, the most common type of childhood arthritis is juvenile idiopathic arthritis, often simply called juvenile arthritis (JA). Like the adult version of this disease, juvenile arthritis is caused by an overly active immune system. For unknown reasons, the immune system attacks the tissues in the joints, causing inflammation, pain, swelling, and stiffness.

Juvenile arthritis follows three basic patterns. About half of all children with the disease have arthritis in four or fewer large joints, including the knees, ankles, or wrists. Doctors call this pauciarticular (PAW-see-are-TICK-u-lar) arthritis. About 40 percent have arthritis in five or more joints, often in smaller joints like the knuckles or toes. This is known as polyarticular arthritis.

The final form of juvenile arthritis, called systemic, affects 10 percent of all patients. This condition may strike any number of joints. But systemic arthritis isn’t limited to the joints. The inflammation may involve internal organs like the heart and liver and often triggers a light skin rash and a fever.

Juvenile arthritis occurs in children 16 and younger. The disease is more common in girls than boys. According to the American College of Rheumatology, about one child of every 1,000 in the United States has the condition.

What are the symptoms of juvenile arthritis?

Like other forms of arthritis, JA causes pain, swelling, and joint stiffness. The symptoms often come and go, or, as doctors say, follow a pattern of flare-ups and remission. The condition is often hard for parents to spot. For one thing, many children — especially young children — don’t complain much about the pain. The most obvious symptom may be stiffness, especially in the early morning or after a long nap. Even a child who wakes up stiff may not tell mom and dad that anything’s wrong. Some parents never suspect a problem until they notice their child limping, acting unusually clumsy, or avoiding physical activity.

Does juvenile arthritis last forever?

Fortunately, juvenile arthritis isn’t always permanent. According to a review of JA studies reported in Pediatrics, about one-third of all patients went into remission from the disease (that is, they no longer showed symptoms of JA). Some forms of JA are easier to manage than others. As reported in a study the Pediatrics article reviewed, an impressive 74 percent of children with systemic arthritis go into remission within five years. In contrast, only 34 percent of children with pauciarticular arthritis and 25 percent with polyarticular arthritis went into remission during that time period.

What are the possible complications?

Many children with juvenile arthritis recover without any long-term effects. In some children, however, the condition can cause permanent damage to joints.

Without treatment, other complications may arise. Roughly 20 percent to 30 percent of children with one type of pauciarticular arthritis develop inflammation of the eye, a condition that can lead to blindness without proper treatment. JA can also cause joints to grow too quickly or too slowly, making one limb shorter than the other. In some cases, a child’s overall growth is stunted.

How is juvenile arthritis diagnosed?

If you think your child might have arthritis, take her to a doctor promptly. The doctor will want a detailed description of the symptoms, including when they started. The National Institutes of Health recommends keeping a record of the symptoms as soon as they appear, because “joint swelling or pain must last for at least 6 weeks for the doctor to consider a diagnosis of JA.” The doctor may also run tests to rule out other possible causes of joint pain, like infections, Lyme disease, or lupus.

There’s no single test for JA, but a doctor can run blood tests to get a better understanding of your child’s condition. Some children with severe cases of polyarticular disease have a certain antibody called IgM rheumatoid factor (RF) in their blood. Children with pauciarticular arthritis may have a different marker called antinuclear antibody (ANA). Patients with this antibody are especially likely to develop eye disease.

Another blood test known as a sedimentation rate test (also called a “sed rate” or ESR test) can help detect inflammation. This test looks at how quickly red blood cells, or erythrocytes, settle in a test tube; if some part of the body is inflamed, certain proteins may cause the red blood cells to clump and fall to the bottom of the tube faster than usual.

However, some children have a normal ESR even though their joints are inflamed. If a doctor thinks the bones may already be damaged, an x-ray may help determine the extent. Occasionally, doctors can also use x-rays to track cartilage damage early in the disease.

What medicines are used to treat juvenile arthritis?

Often, simple over-the-counter painkillers like ibuprofen (Advil, Motrin) and naproxen sodium (Aleve) can greatly ease a child’s symptoms and help him get back to a normal life. But just because these drugs are available at the convenience store doesn’t mean you should take matters into your own hands. Your child’s doctor can help you choose the right medication for your child.

Be aware that over-the-counter painkillers can cause severe problems if misused. Aspirin, for instance, can cause liver damage or bleeding stomach ulcers; when given to a child with a viral infection, it can cause Reye’s syndrome, a potentially life-threatening disease. Because of this, children should not take aspirin. Whatever type of medication the doctor recommends, watch out for possible side effects (such as black stools or abdominal pain and cramping) and report them to your physician promptly.

A doctor may prescribe a drug that attacks the disease itself, rather than simply controlling the symptoms. So-called disease-modifying anti-rheumatic drugs (DMARDs) can keep the body from turning against itself and help prevent further damage to bones and joints.

The most commonly prescribed traditional DMARD is methotrexate, a drug that slows down the immune system. According to Pediatrics, studies show that 60 to 80 percent of JA patients improve while taking methotrexate. In small doses, methotrexate is generally safe.

However, about 13 percent of kids have stomach trouble, and there’s always a chance that liver damage may occur, though it’s much less common in kids than in adults. Many doctors recommend regular liver tests for any child taking the drug. And because methotrexate weakens the immune system, a doctor may refrain from giving live-virus vaccines to a child on the drug. Check with your doctor about other drugs that can be used to treat juvenile arthritis.

As with methotrexate, it pays to be cautious with any medicine that affects the immune system. Many DMARD drugs have a black box warning — the most serious drug warning the Food and Drug Administration issues. Children should be current on all of their immunizations before taking the drug, and they shouldn’t take the drug within three months of receiving a live-virus vaccine. To be extra safe, they should briefly stop taking the drug if they’ve been exposed to chickenpox. (Always check with a doctor before stopping any drug.)

Some biologic drugs, including Enbrel, have also been used as second-line treatments for juvenile arthritis. Enbrel has been been associated with certain infections, including tuberculosis; it has also been associated with an increased risk of lymphoma when used in children and teens and has a black box warning, according to the FDA.

In severe cases of JA, doctors might combine powerful drugs called corticosteroids with other treatments. These drugs can dramatically reduce inflammation. However, long-term use of the drugs can cause many serious side effects, including weakened bones and a vulnerability to infections. Once symptoms are under control, a doctor will slowly reduce the dose to lower the risk of complications.

What else can I do to help my child?

First of all, treat your child normally. His arthritis shouldn’t change your love, discipline, or expectations. Your child may need to rest during flare-ups, but he should stay as active as possible when symptoms fade. Regular exercise will help keep his joints strong and flexible. A physical therapist can help recommend exercises and activities that will be especially helpful. Above all, let your child know that he isn’t alone. Tell him that many children have faced JA — and many have gotten better.

References

Updated Guidelines on Juvenile Arthritis, American College of Rheumatology,

National Institutes of Health. Health Topics: Questions and answers about juvenile rheumatoid arthritis.

Follow-up to the June 4, 2008 early communication about the ongoing safety review of tumor necrosis factor (TNF) blockers (marketed as Remicade, Enbrel,Humira, Cimzia, and Simponi), U.S. Food and Drug Administration.

American Academy of Orthopedic Surgeons. Juvenile Rheumatoid Arthritis.

American College of Rheumatology. Juvenile Arthritis.

Coping with Juvenile Rheumatoid Arthritis. American Academy of Orthopaedic Surgeons, undated.

Arthritis Foundation. Juvenile Rheumatoid Arthritis. JA Alliance.

Arthritis Foundation. Pauciarticular JRA.

Hashkes, PJ et al. Medical Treatment of Juvenile Idiopathic Arthritis. Journal of the American Medical Association. Volume 294, Number 13.

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