Juvenile Idiopathic Arthritis (JIA) is the most common type of arthritis that affects children. It used to be known as juvenile rheumatoid arthritis, but the name was recently changed to reflect the differences between childhood arthritis and adult forms of rheumatoid arthritis.
JIA is a chronic (long-lasting) disease that can affect joints in any part of the body. In this disease, the immune system mistakenly targets the synovium, the tissue that lines the inside of the joint. The synovium responds by making excess fluid (synovial fluid), which leads to swelling, pain and stiffness. The synovium and inflammation process can spread to the surrounding tissues, eventually damaging cartilage and bone. Other areas of the body, especially the eyes, also may be affected by the inflammation. Without treatment, JIA can interfere with a child’s normal growth and development.
The exact cause of JIA is not known. However, researchers are studying several factors that may be involved, alone or in combination, in triggering the inflammatory reaction seen in JIA. These factors include genetics, infection, and environmental factors that influence the immune system. JIA, however, is not a hereditary disease like cystic fibrosis, for example.
How Common Is JIA?
JIA is the most common type of arthritis in children. It affects about 1 in 1,000 children, or about 300,000 children in the United States.
Symptoms vary depending on the type of JIA and may include:
There are no tests that specifically diagnose JIA. Rather, JIA is a diagnosis of exclusion, which means the doctor works to rule out other causes of arthritis and other diseases as the cause of the symptoms. In making a diagnosis of JIA, the doctor usually begins with a complete medical history that includes a description of symptoms, and a complete physical examination. Imaging techniques such as X-rays or magnetic resonance imaging (MRI) can sometimes show the condition of the joints. Laboratory tests on blood, urine, and/or joint fluid may be helpful in determining the type of arthritis. These include tests to determine the degree of inflammation, antinuclear antibody (ANA), and rheumatoid factor. These tests also can help rule out other diseases — such as an infection, bone disorder, or cancer — or an injury as the cause of your child’s symptoms.
The goals of treatment are to relieve pain, reduce swelling, increase joint mobility and strength, and prevent joint damage and complications. Treatment generally includes medications and exercise. Medications used to treat JIA include:
Exercise and physical and occupational therapy can help reduce pain, maintain muscle tone, improve mobility (ability to move) and prevent permanent handicaps. In some cases, splints or braces also may be used to help protect the joints as the child grows.
What Is The Outlook For People With JIA?
JIA affects each child differently. For some, the disease is mild and easy to control, with only one or two joints affected. For others, JIA may involve many joints and the symptoms may be more severe and may last longer. With the help of modern medical, physical, and occupational therapy, it is possible to achieve good control of the arthritis, prevent joint damage, and enable normal or near-normal function for most patients. Early detection and treatment may help to control inflammation, prevent joint damage, and maintain your child’s ability to function.
What Complications Are Associated With JIA?
If it is untreated, JIA can lead to:
What Are Some Common Eye Problems That Might Affect Children With JIA?
Uveitis is the most common eye problem that can develop in children with JIA. Uveitis is an inflammation of inner parts of the eye. The uvea consists of the iris (the colored portion of the eye), the ciliary body (which produces fluid inside the eye and controls the movement of the lens) and the choroid (which lines the eyeball from the iris all the way around the eye).
Uveitis might also be known as iritis or iridocyclitis, depending on which part of the eye is affected by inflammation.
If the inflammation is not detected and treated early, scarring and vision problems can occur.
Glaucoma, cataracts, and permanent visual damage (including blindness) are all complications that could result from severe uveitis.
Uveitis can occur up to one year before, at the same time as, or up to 15 years after JIA is diagnosed. It can also occur several years after JIA is in remission (the disease is not active). The severity of the child’s joint disease does not determine how serious the uveitis might be.
However, eye problems are more common in children with oligoarthritis (less than five joints with arthritis in the first 6 months of disease). Eye problems are also more likely if your child has a positive blood test for antinuclear antibodies (ANA). They are most likely to occur in female toddlers.
How Will I Know If My Child Is Developing Eye Problems?Because eye inflammation usually is not painful and the eyes are usually not red (“pink”), most children with JIA who develop eye problems do not have any symptoms.
Rarely, children might complain of light bothering their eyes or blurred vision. Sometimes your child’s eyes might look red or cloudy. However, these symptoms usually develop so slowly that permanent eye damage can occur before any visual difficulties are noticed.
In order to detect eye problems and prevent them from causing damage, your rheumatologist will schedule frequent appointments with a pediatric ophthalmologist.
What Happens During An Ophthalmologist Appointment?
The eye exam performed by the ophthalmologist is painless and lasts several minutes. Be sure to tell the ophthalmologist about the medicines your child is taking. (Your rheumatologist can tell you the names of the medicines, the dosages, and why they have been prescribed.)
Prior to the eye exam, the ophthalmologist will put drops in your child’s eyes (which might burn a little) to make the pupils bigger (dilate). Dilating your child’s eyes helps the doctor clearly view the inside of the eyes.
To detect eye inflammation, the ophthalmologist uses a special microscope called a slit lamp. The machine shines a thin beam of light into one eye at a time so the doctor can view the inside of the eyes. A visual field exam might also be performed to detect vision changes.
How Can Eye Problems Be Treated?
If eye problems occur, your rheumatologist and ophthalmologist will discuss ways to treat them to prevent permanent eye damage. If uveitis is diagnosed, different types of eye drops might be prescribed. Eye drops to dilate the eyes may be prescribed in order to keep the pupils open and help prevent scarring.
Steroid (cortisone) drops might be prescribed to reduce swelling and decrease inflammation. However, long-term use of steroid eye drops can have significant side effects such as glaucoma and cataracts.
If eye drops are not effective in decreasing the inflammation, oral steroids (taken by mouth) might be prescribed. Oral or injectable methotrexate is now often used to treat significant eye inflammation so the long-term side effects of steroids can be avoided. In cases of severe uveitis, new “biologic modifying medicines,” such as infliximab (Remicade®) or adalimumab (Humira®) may be used.