Juvenile Idiopathic Arthritis - Causes

Causes

So far the actual cause of JIA remains a mystery. However, the disorder is autoimmune - meaning that the body's own immune system starts to attack and destroy cells and tissues (particularly in the joints) for no apparent reason. It is believed that the immune system gets provoked by changes in the environment or perhaps there is an error in the gene. Experimental studies have shown that certain viruses that have mutated may be able to trigger JIA. JIA appears to be more common in young girls and the disease is most common in Caucasians. Associated factors that may worsen or have been linked to rheumatoid arthritis include the following:

• genetic predisposition; it appears that when one family member has been diagnosed with rheumatoid arthritis, the chances are higher that other family members or siblings may also develop arthritis

• females are more likely to develop rheumatoid arthritis than males at all ages

• there is a strong belief that psychological stress may worsen the symptoms of rheumatoid arthritis. However, when the emotional stress is under control the arthritis symptoms do not always disappear suggesting that the association is not straightforward

• even though no distinct immune factor has been isolated as a cause of arthritis, there are some experts who believe that the triggering factor may be something like a virus which then disappears from the body after permanent damage is done

• because rheumatoid arthritis is more common in women, there is a belief that perhaps sex hormones may be playing a role in causing or modulating arthritis. Unfortunately, neither sex hormone deficiency nor replacement has been shown to improve or worsen arthritis.

The cause of JIA, as the word idiopathic suggests, is unknown and currently an area of active research. Current understanding of JIA suggests that it arises in a genetically susceptible individual due to environmental factors.