Arthritis is generally considered a disease of the older population, but about 294,000 children younger than 18 have some type of arthritis, according to the National Institute of Arthritis and Musculoskeletal and Skin Diseases.

There are several subsets of juvenile arthritis that fall under the umbrella term ‘juvenile ideopathic arthritis' (JIA). The first clue many parents have that something is amiss occurs when the child appears to limp or suffer stiffness after getting out of bed in the morning.

“Juvenile arthritis presents with joint swelling, stiffness in the morning or after rest, or limp. It may be mildly painful but is often painless,” says Dr. Kevin Baszis, a pediatric rheumatologist with Washington University Physicians. “These symptoms must be present for at least six weeks to diagnose a child with JIA. This six-week time point is chosen because a temporary arthritis can be seen after certain infections or reactions to medications, and this temporary arthritis typically resolves in less than six weeks and does not become chronic.”

Although it is not known why some children develop JIA, it is a form of autoimmune disease in which the immune system attacks the joints, causing the symptoms. “We can say with some certainty that autoimmune diseases seem to have a genetic predisposition, meaning that certain people are just programmed by their DNA to be at higher risk for developing one. However, we also think that this programming usually is not enough to cause an autoimmune disease. There must be some trigger,” says Dr. Brad Ornstein, a specialist in pediatric infectious disease and rheumatology with Mercy Children's Hospital.

Autoimmune triggers are a mystery, but some researchers suspect that viral or bacterial infections may play a role. Others surmise that environmental factors, such as trauma or stress, activate the autoimmune process.

Beyond joint swelling and stiffness, children with JIA are more likely to experience uveitis, or inflammation of the eyes. “Similar to JIA, this eye inflammation is autoimmune in nature,” Baszis says. “Uveitis is often asymptomatic, and for this reason, children with JIA must have frequent eye exams by an ophthalmologist, as often as every three months.”

The good news is that JIA can be treated and most children with the disease are able to enjoy all the typical activities of childhood. “The goal of therapy in this day and age is complete remission,” Ornstein says. “For all intents and purposes, JIA is not ‘curable’ at this point. However, many children are able to live basically disease-free and off of all medications after an initial period of therapy.”

A healthy, balanced diet and regular exercise are recommended, but little evidence exists to support the efficacy of specific alternative therapies or supplements. In fact, Ornstein sounds a warning: “When it comes to herbal medications, I feel it is important to state that although many people view these therapies as being ‘more natural,’ these supplements are chemicals, too. Moreover, they are chemicals that have little to no solid data to support their efficacy or governmental bodies to regulate them or the claims made by their manufacturers. I always strongly advice my patients to avoid these things.”

Even if your child does not complain of joint pain, if you notice limping or stiffness after rest that persists for weeks with no apparent explanation, such as a sports injury, see your primary-care physician. With proper treatment, JIA won’t slow kids down.

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