Juvenile idiopathic arthritis (JIA) has previously been referred to as juvenile rheumatoid arthritis or juvenile chronic arthritis. This is the most common chronic form of joint inflammation in children. JIA is a puzzling disease that is often difficult to diagnose and for parents to understand. Common symptoms are persistent joint stiffness and swelling of one or multiple joints, pain, and unexplained fever. If your child has any of these symptoms—and/or an unusual pattern of walking, especially in the morning or after naps, call your pediatrician. Surprisingly, many and perhaps even most children with JIA do not complain of pain when they first develop symptoms of the disease.
JIA occurs most often in children between the ages of three and six years or around the time of puberty. It is unusual for JIA to begin under one year of age or after age sixteen. Although this condition can be disabling, with proper treatment many children fully recover by the time of puberty.
The exact cause of JIA is still unknown. Researchers believe that JIA may be triggered by or perhaps is related to a viral infection in children who have an abnormality in their immune (disease- resistance) system. In some children the virus causes only a mild illness. But for others, the virus causes the immune system to overreact and trigger inflammation, joint swelling, and pain.
The signs, symptoms, and long-term effects can vary depending on the type of JIA. A form of JIA known as systemic JIA causes not only fever and painful joints, but also may damage internal organs. When systemic JIA strikes the internal organs, the child can develop either pericarditis (an inflammation of the outer covering of the heart), myocarditis (an inflammation of the heart muscle), pleuritis (an inflammation of the lining of the lungs), or pneumonitis (an inflammation of the lung tissue itself). Inflammation can also occur in the brain and its lining; this condition is called meningoencephalitis, but it is less common than the other conditions described above.
There are two other types of JIA—pauciarticular JIA (affecting one or more joints) and polyarticular (affecting many joints). Pauciarticular JIA can be associated with inflammation of the eye, which in turn can cause glaucoma or cataracts. Pauciarticular JIA is the most common form, most often affecting young girls. It also has the best prognosis relative to disability and ultimate outcome.
Great strides are being made in treating JIA and other forms of arthritis. Treatment varies depending on the type of arthritis a child has, and often includes medication, exercise, physical therapy, and possibly splints. It is important to follow the treatment recommended by your doctor to ensure the best outcome for the child.
For JIA, therapy aims to reduce inflammation. Aspirin may be used initially in children with mild disease since it decreases joint inflammation and pain. Aspirin is also fairly inexpensive and easy to give. In some children, however, aspirin can have some undesirable side effects, such as stomach upset. In addition, aspirin therapy must be stopped if the child has chickenpox or flulike illnesses, related to a disease called Reye syndrome. If aspirin is not working or produces unacceptable side effects, your pediatrician may recommend the use of nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen. Like aspirin, these are rapid-acting drugs, but less likely to cause side effects.
Particularly for children with many joints affected by arthritis, it is becoming increasingly common to turn to medications that stop the rapid overgrowth of the joint-lining tissue, or reduce inflammation. If the JIA is severe and is not getting better with first-line treatment, your pediatrician may refer your child to a pediatric rheumatologist for this type of treatment. Such medications require careful monitoring but can greatly improve the lives of children with arthritis.
Other therapies also are available and have been shown to help children with inflammation in one or two joints. For example, an anti-inflammatory steroid medication can be injected directly into the affected joints, and can rapidly restore your child’s function in even severely affected joints.
Although there is no way to prevent JIA, it is possible to slow the disease’s progression. Exercise plays an important role in slowing the progression of JIA and preventing the joints from getting too stiff. Although it may be uncomfortable at times, especially when a child’s joints are already sore, it is important for parents to help their child work through the discomfort for the long-term benefits.
Living with JIA requires a great deal of adjustment, not only for the ill child but also for her parents and other family members. But working as a team will help decrease the risk of the child having long-term problems or consequences. Your pediatrician can recommend arthritis organizations that can provide useful information about this complex disease.