| One of the most frequent chronic diseases of | | | | disability due to the arthritis causes significant |
| children and the most common rheumatological | | | | psychological distress, behavioural problems, anxiety |
| condition in this group is juvenile rheumatoid arthritis. | | | | and depression. The polyarticular and oligoarticular |
| This is not one disorder but a group of interrelated | | | | forms occur more often in girls than boys with a |
| disorders which all exhibit inflammatory changes in the | | | | frequency of three to four and a half to one. The |
| joints. The triggering factors for these diseases have | | | | systemic form occurs equally. |
| not been uncovered and it has proven hard to | | | | The polyarticular or many affected joint form of |
| delineate one particular type of condition from | | | | arthritis has two peaks of incidence, one covering |
| another due to the complex genetic factors. While it | | | | one to four years of age and another covering six to |
| is often called JRA, there is a move to standardise | | | | twelve years. The fewer joint type, the oligoarticular |
| the naming of these diseases into juvenile idiopathic | | | | form, tends to occur in children who are two to four |
| arthritis. | | | | years old. The systemic type has no particular age of |
| Three main divisions of juvenile rheumatoid arthritis | | | | incidence. The disease pattern over the first six |
| can be described, that affecting many joints which is | | | | months determines which pattern the individual |
| called polyarticular, that involving few joints and | | | | patient fits into. If four or fewer joints are affected |
| termed pauciarticular and a more body wide disease | | | | during this period then the diagnosis is the |
| onset known as systemic arthritis. The arthritis is a | | | | oligoarticular or fewer joint group. More than five |
| chronic disease which flares up at times and then | | | | joints are symptomatic during the first six months |
| goes into remissions, with targeting of the medical | | | | this indicates the polyarticular or many joint diagnosis. |
| treatment towards the induction and maintenance of | | | | Arthritis, rashes and a fever are the typical onset |
| a remission. Recent advances in the development of | | | | symptoms of the systemic form. |
| drugs have produced the biological agents which are | | | | If a diagnosis of juvenile arthritis of some form is to |
| much more effective for arthritic diseases. | | | | be made then the patient should have arthritis of |
| The triggering factors for juvenile rheumatoid arthritis | | | | some of their joints for at least six weeks. Stiffness |
| have not been clearly identified, with a possible | | | | in the morning or after periods when the joint has |
| trigger of trauma or infection developing an | | | | been kept still is a typical complaint. The start of the |
| autoimmune attack against joint tissues. The synovial | | | | disease can be very sudden and dramatic or may |
| lining of the joint increases in bulk and develops | | | | come on slowly over some time, with common |
| chronic inflammation, with perhaps some genetic | | | | symptoms including stiffness of the joints as |
| vulnerability contributing to this process. A group of | | | | mentioned, joint pain in the day, periods of absence |
| genes are understood to be involved in the pattern | | | | from school and a limping gait. Some patients also |
| of disease presentation and the nature of its onset. | | | | suffer from inflammatory disease of the bowel. A |
| There are many factors which influence the incidence | | | | child may not always report actual pain in a joint but |
| of these types of arthritic diseases, such as how | | | | instead they may just allow the joint to go unused |
| susceptible individuals are and the population types | | | | and develop atrophy or a joint contracture. |
| involved. | | | | In the systemic form of juvenile arthritis the child |
| The oligoarticular type of juvenile chronic arthritis, in | | | | suffers from fevers which spike once or twice a day |
| which a small number of joints are inflamed, is the | | | | at around the same time, the temperature typically |
| commonest disease type, consisting of about half of | | | | returning back to normal each time. This pattern is |
| all patients. Thirty percent have a large number of | | | | different from infections so helps to distinguish what |
| joint affected, the polyarticular type, and the rest | | | | the patient is suffering from. These patients usually |
| have the systemic form. Sufferers from chronic | | | | show a short lasting rash over the trunk and limbs, |
| juvenile arthritis may at some type suffer also from | | | | joint pain often in the bigger joints and appear to be |
| another autoimmune disorders. The severe pain and | | | | unwell. |