JRA = Juvenile Rheumatoid Arthritis
The name de jour is JIA. Juvenile arthritis was once thought to be like full blown rheumatoid arthritis (RA) but in children rather than adults. Hence JRA. And then some bright spark pointed out that juvenile arthritis isn't like RA in all respects and along came JIA as a moniker.
JRA is still in use by many people, but JIA is seen as being more accurate these days. If I could be bothered I'd do some research and find out just how long the term JIA has been in use. But I can't be bothered.
- Juvenile - Children (or not adults, I'm sure lots of teenagers will get worked up at being labelled a child)
- Idiopathic - (this is the good bit) Without Known Cause. Yes, indeedy, idiopathic means the doctors having got a flaming clue what causes this.
- Arthritis - Inflammation of joints (from Greek arthro-, joint + -itis, inflammation. Greek bits courtesy of wikipedia: http://en.wikipedia.org/wiki/Arthritis)
I'm happy to relate that according to the same page that they got it slightly wrong in House. The lovely Hugh Laurie (House) says that idiopathic: "comes from the Latin, meaning 'we're idiots, because we don't know what's causing it.'" But, unfortunately, idiopathic comes from Greek, not Latin. Whoops.
So there it is, PuffyFingers and many other children like her have inflammed joints and no-one knows why.