What is Juvenile Arthritis?
Juvenile Arthritis (JA) is an umbrella term for at least three forms of childhood arthritis, each with a different pattern and prognosis. In some literature, the term Juvenile Arthritis is used synonymously with Juvenile Rheumatoid Arthritis and Juvenile Chronic Arthritis. According to the classification scheme most commonly used in North America, Juvenile Arthritis occurs in someone younger than 16 years of age at onset and persists for more than 6 weeks in one or more joints and other causes of arthritis have been excluded. Joints affected with arthritis will demonstrate swelling or effusion, warmth, pain, decreased range of motion and tenderness with joint movement or pressure. Children usually complain of stiffness on rising and after napping.
Types of Juvenile Arthritis
1. PAUCIARTICULAR- ONSET JUVENILE ARTHRITIS
This is the most common of the three major subtypes. Pauciarticular JA is defined as 4 or fewer joints affected over time. Children tend to have the mildest case of arthritis which are generally controlled with first line drugs (nonsteroidal anti-inflammatory drugs) and their arthritis usually goes into remission within a few years of onset. These children tend to have more problems with their eyes (uveitis) than with their joints.
Pauciarticular-onset JA can be divided into two groups that have a different clinical picture.
Early Onset Pauciarticular JA patients are most often girls who are less than 5 years of age at onset and have a positive ANA test. Onset is gradual and usually affects knees, ankles, wrists and ankles but rarely hips. These children have the highest risk of chronic uveitis. This is (usually asymptomatic) inflammation of the iris and uveal tract of the eye that, if left untreated, may result in loss of vision from scarring
Late Onset Pauciarticular JA is seen mostly in boys over 9 years of age and the joints affected tend to be hips and other joints of the legs. They frequently have a family history of arthritis and more than 40% go on to develop adult symptoms. These boys frequently have acute uveitis which has visible symptoms making it easier to diagnose and treat.
2. POLYARTICULAR- ONSET JUVENILE ARTHRITIS
Polyarticular JA is defined as involving 5 or more joints. Girls are more often affected than boys. Often as many as 20 joints are affected and these include both large and small joints. It is usually symmetrical. This type of JA often requires second-line drugs to bring it under control. There are systemic manifestations including fever and weight loss. There tends to be two groups of children that fall into this category. The first are much younger at onset of the disease and the second group, with older age onset tend to have more erosive, adult-like disease.
3. SYSTEMIC- ONSET JUVENILE ARTHRITIS
Children, boys and girls equally, present with a high fever (to 105 F/ 30 C or above) that spikes once or twice daily. This is accompanied by a rash, fatigue, appetite and weight loss, enlarged lymph nodes and anemia. In some cases there is also pericarditis, pleuritis and hepatitis. The joint systems tend to be joint and limb pain rather than truly inflamed points or arthritis. These systemic symptoms do not usually last more than 6 months and the disease then progresses to a polyarticular or pauciarticular course.
Early diagnosis and treatment are very important. The overall goals of treatment are to improve function, reduce deformity and try to try to prevent permanent joint damage in addition to maintaining as normal a social development as possible.
Treatment for Juvenile Arthritis includes:
- Drug Management in the form of first line or non-steroidal anti-inflammatory drugs to reduce pain, swelling, and stiffness and second line or disease modifying antirheumatic drugs for prolonged arthritis that would lead to permanent damage as well as other more toxic drugs in the case of severe forms of the disease
- Physical and Occupational Therapy to improve range of motion and muscle strength. This is accomplished through passive and active exercises, splinting, positioning, the use of heat/cold, careful instruction regarding conservation of energy and protection of joints including adequate rest and provision of adaptations as needed to achieve function.
What is the Course of the Disease?
Juvenile Arthritis may only last as little as several months to a year but is more likely to follow a pattern or ups and downs for a number of years. These are called flare-ups or exacerbations and remissions. Usually the cause of the flare is not identifiable although it may be related to a cold or flu-like illness. For most children, flare-ups become less and less severe and less and less frequent over time.
What Causes Juvenile Arthritis?
No one knows what causes JA but it appears to involve abnormalities of the immune system. It does not appear to be passed to be passed from parent to child.
Melvin, Jeanne L. and Wright, F. Virginia (2000) Rheumatologic Rehabilitation Series – Volume 3: Pediatric Rheumatic Diseases. AOTA: Bethesda MD.
The Arthritis Society
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