Diseases & Conditions
Juvenile Rheumatoid Arthritis
The most common type of juvenile ARTHRITIS, which is an inﬂammation of the joints characterized by swelling, heat, and pain. Arthritis can be short-term or chronic, and in rare cases it can last a lifetime. Juvenile arthritis is the term used for all the types of arthritis that affect more than 285,000 children in the United States. Juvenile rheumatoid arthritis (JRA) affects about 75,000 American children.
Doctors do not know what causes rheumatoid arthritis (also called idiopathic arthritis) in children, but research suggests that it is an autoimmune disease. In autoimmune diseases, white blood cells lose the ability to tell the difference between the body’s own healthy cells and tissues and harmful bacteria and viruses. The immune system, which is supposed to protect the body from invasion, instead releases chemicals that can damage healthy tissues and cause inﬂammation and pain.
JRA usually appears between the ages of six months and 16 years. The ﬁrst signs are often joint pain or swelling and reddened or warm joints. Rashes may suddenly appear and disappear, developing in one area and then another. High fevers that tend to spike in the evenings and suddenly disappear are characteristic of systemic JRA.
There are several types of JRA; which type a child has is determined by the pattern of symptoms that occurs within the ﬁrst six months. About half the time children eventually outgrow the disease, but it is hard to predict who will continue to suffer with symptoms. Often the more joints that are affected, the more severe the disease and the less likely that the symptoms will eventually go away.
The three major types of JRA are polyarticular arthritis, pauciarticular JRA, and systemic JRA.
polyarticular arthritis primarily affects girls, causing swelling or pain in ﬁve or more joints. The small joints of the hands are affected as well as the weight-bearing joints such as the knees, hips, ankles, feet, and neck. There may be a low-grade fever as well as bumps on the body in areas subjected to pressure from sitting or leaning.
pauciarticular JRA affects fewer than four joints; the knee and wrist joints are most often involved. Symptoms include pain, stiffness, or swelling of affected joints. In this subtype of JRA, an inﬂammation of the iris of the eye may occur with or without active symptoms. This eye inﬂammation, called iridocyclitis or iritis or uveitis, can be detected by an ophthalmologist.
systemic JRA affects the entire body, with high fevers that rise at night and then suddenly drop to normal. During the onset of fever, the child may feel very ill, appear pale, or develop an intermittent rash. The spleen and lymph nodes may become enlarged. Eventually many of the body’s joints are affected by swelling, pain, and stiffness.
To effectively manage and minimize the effects of arthritis, an early and accurate diagnosis is essential. Many viral infections can cause a brief bout of arthritis that then disappears. If the arthritis has not cleared within six weeks, a rheumatologist or other specialist should be consulted.
Diagnosis begins with a detailed medical history and a thorough physical examination. X rays or blood tests may be used to exclude other conditions that can mimic JRA. Tests may include:
• a complete blood count to evaluate all the basic cellular components of blood, including red blood cells, white blood cells, and platelets. Abnormalities in the numbers and appearances of these cells can be useful in the diagnosis of many medical conditions.
• a blood culture to detect bacteria that cause infections in the bloodstream. A blood culture may help rule out infections.
• bone marrow examination reveals the condition of blood where it is being formed to rule out conditions such as leukemia.
• erythrocyte sedimentation rate checks how rapidly red blood cells settle to the bottom of a test tube. This rate often increases in people when inﬂammation is occurring in the body.
• rheumatoid factor, an antibody produced in the blood of children with some forms of JRA. Rheumatoid factor is much more common in adults.
• antinuclear factor (ANA), a blood test to detect autoimmunity that can predict which children are likely to have eye disease with JRA
• X rays and bone scans can detect changes in bone and joints to evaluate the causes of unexplained bone and joint pain.
JRA is treated with a combination of medication, physical therapy, and exercise. Sometimes a child may need surgery or corticosteroid shots into the joint. The goals of treatment are to relieve pain and inﬂammation, slow down or prevent the destruction of joints, and restore use and function of affected joints.
NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDs) may be prescribed for inﬂammation and pain. Although swelling and pain may temporarily improve, it is important to continue medication until a doctor decides that the disease is fully controlled. If NSAIDs do not control inﬂammation of the joints, other medications such as methotrexate may be prescribed.
New biological agents are available to treat some forms of chronic arthritis in children. Etanercept, Enbrel, and Remicads are approved for use in children with polyarticular JRA, while inﬂiximab is currently being tested for use in some types of childhood arthritis.
A physical therapy program is essential in managing any type of arthritis, including activities and exercises suited to a child’s speciﬁc condition. Range-of-motion exercises can restore ﬂexibility in stiff, sore joints, and other exercises will build strength and endurance. It is very important for children with arthritis to maintain a regular exercise program so that muscles are kept strong and healthy to help support and protect joints. Regular exercise also helps to maintain range of motion of joints and prevent cycles of pain and depression. Safe activities include walking, swimming, and bicycling (especially on stationary bikes). However, some sports (especially impact sports) can be hazardous to a child whose arthritis has weakened joints and bones.
A child with arthritis should also be sure to eat a balanced diet that includes plenty of calcium to promote bone health.