Juvenile arthritis is the most common rheumatic disease in children, affecting one in 1,000, explains Dr Orla Killeen, consultant paediatrician at Our Lady's Hospital in Crumlin.
Treatment involves a multidisciplinary team including an occupational therapist, a child psychologist and a physiotherapist.
Like many auto-immune diseases, it is much more common in girls than in boys, with girls twice as likely to suffer from it.
There is no cure, but 50 to 60 per cent of cases will "burn out" by the time they reach adulthood. Early diagnosis and appropriate treatment are the best ways of promoting remission.
Historically, the condition was treated with rest, immobilisation and steroids, which can have many side effects.
In the last two decades, the treatment has also involved methotrexate, a disease-modifying anti-rheumatic drug. It is essentially an immune suppressant drug and "calms down the over-reaction" in the system, Killeen says.
Between 20 and 30 per cent of all cases of juvenile arthritis also involve uveitis - an inflammation of the eye. It is asymptomatic, so it is important for the child to have regular check-ups with an ophthalmologist.
Dr Killeen is the State's only juvenile arthritis consultant, but she says there is a need for at least three more.
For further information, contact Arthritis Ireland on 01 - 661 8188.