What is Juvenile Rheumatoid Arthritis?
Juvenile rheumatoid arthritis (JRA), also know as juvenile idiopathic arthritis, is predominantly seen in infants, children, and adolescents aged 16 years or less. It can affect any joint in the body causing inflammation. Though the cause of the disease is unknown, it is understood that the condition is an autoimmune disorder.
Types of Juvenile Rheumatoid Arthritis
Juvenile rheumatoid arthritis is classified into three types:
- Pauciarticular JRA is the most common type of JRA and affects four joints or less after more than 6 months from the start of the disease. 50% of those affected by JRA have this type of JRA. This type mostly affects the large joints of the body such as the elbow and knee, though the hip is not usually affected. The onset of eye problems such as iritis and uveitis is a possibility. This type does not affect joints on both sides of the body simultaneously.
- Polyarticular JRA is a type that affects five or more joints in the body. Close to 30% of those affected by JRA suffer from this type of JRA. Smaller joints such as the fingers and wrists are generally affected, though large joints may also be affected. Polyarticular JRA affects joints on both sides of the body simultaneously.
- Systemic JRA is suffered by around 20% of those affected by JRA. In this type, arthritis is accompanied by high fever and a pinkish rash that appears and disappears. Apart from affecting joints, internal organs such as the kidney, liver, and heart may also be affected by this type. Unlike the other two types which commonly affect girls, this type can affect boys as much as girls.
How common is Juvenile Rheumatoid Arthritis in Children?
Studies suggest one in every thousand children is affected by arthritis and one in every ten thousand children is affected by severe arthritis. The most commonly seen form of severe arthritis is JRA.
Causes and risk factors for juvenile rheumatoid arthritis
The disease is known to be an autoimmune disorder. This means the body fails to recognize some of its cells and tissues as its own and attacks them with antibodies. Though joint tissues are most commonly affected, other tissues and internal organs can be affected by this disorder as well.
The cause, though not known, is speculated to be a combination of genetic susceptibility and microbial infection or allergy. In any case, the body produces a certain type of protein which it does not recognize as its own and sends antibodies to destroy cells with that protein. The resulting body reaction is inflammation of the region of attack, followed by other symptoms of the disease.
Its is observed that JRA affects girls in higher percentage than boys and that Caucasians are affected by this more than any other race.
What are the Signs, Symptoms, and Treatment of the different forms of Juvenile Rheumatoid Arthritis?
Symptoms of JRA are known to show in children as young as 6 months old. The most common sign of JRA is swelling in one or more joints. Another sign is stiffness of joints which may be observed if the child is seen limping after waking up from sleep. The child may also complain of pain in the joints.
Treatment for JRA is primarily aimed to reduce inflammation and pain. This is done through medication as well as procedures to let excess joint fluid out, in turn relieving joint pressure and reducing the inflammation and pain.
Pauciarticular JRA, due to the asymmetrical nature of the arthritis attacks, may lead to uneven growth of the body, resulting in the arms or legs being longer on one side, causing the child to limp or have dexterity problems. Other complications include certain eye diseases, which if ignored, can lead to lifelong eye problems and even blindness. This type is treated with mid doses of non-steroidal anti-inflammatory drugs (NSAIDs) to reduce inflammation and the resulting increase in blood flow to one side of the body. This even helps in growth on both sides of the body. Eye tests must be done once every 3 months to prevent the onset of eye diseases.
Since polyarticular JRA affects more joints, the affected child may experience more pain and have a more difficult time with normal activities. This type is also treated with NSAIDs and in severe cases, steroidal medication is given.
Since systemic JRA involves fever and rashes, appropriate medicine is given to address both along with NSAIDs and steroidal medication depending on the severity and frequency of the inflammation.
Diagnosis of Juvenile Rheumatoid Arthritis
The fact that joint pain in children can stem from a number of factors makes JRA difficult to diagnose. Doctors use a number of tests to rule out symptoms of other diseases.
- Visual inspections may indicate swollen liver and lymph nodes.
- Blood tests are made to detect the presence of the rheumatoid factor and anti-nuclear antibodies (ANA), which are commonly found in children with JRA. But there can be cases of JRA where the rheumatoid factor and ANAs are absent.
- X-rays of the joint and samples of joint fluid are taken to inspect the condition of the joint to rule out other causes of pain such as cancers or fractures.
In case of systemic JRA, tests are also done to rule out the possibility of rashes and fever being a byproduct of an infection.
Juvenile rheumatoid arthritis studies and other tests
Severe cases of JRA may be treated with experimental drugs such as disease modifying anti-rheumatic drugs (DMARD) and biological response modifiers (BRF) such as TNF blockers which work to eliminate the tendency of inflammation altogether. These carry significant side effects which must be considered before administration. Alternative treatments include hot and cold packs for pain relief.
Studies show that children with JRA might be prone to have poor appetites, and might gain weight abnormally due to the effect of medication and an intolerance or aversion to exercise. Physical and diet therapy helps reduce chances of muscle and bone degeneration due to the above.
Around 50,000 children in the United States of America have been recorded to be affected by the disease. Experts say that though symptoms of pauciarticular JRA are seen to eventually withdraw in many cases, other types do persist and their symptoms have lower probability to disappear on their own accord.