24th February 2025

Overview of JIA

JIA describes a collection of inflammatory arthritides that occur in children of any age below 16 years old (but typically less than six years old), with an incidence of approximately 1:1000. There are a number of subsets described including oligo-JIA, poly-JIA and systemic-JIA. The pathophysiology is thought to be similar in mechanism to that of RA.

Historically, the diagnosis of JIA was delayed, in part due to the wide differential list. A high index of suspicion is required for what is a clinical diagnosis, and in suspected cases, treatment should begin prior to being seen by a Paediatric Rheumatologist. Primarily, this is to provide timely pain relief but also to rapidly limit the degree of joint damage, which can lead to subsequent growth restriction and later deformity.

Management typically involves intra-articular or systemic corticosteroid, whilst DMARDs take effect. On occasion, biologic therapies are required. Interestingly, 10-20% of JIA cases are associated with uveitis and so prompt referral to Ophthalmology is prudent. Otherwise, holistic management is best achieved via a multidisciplinary team approach, including psychological support. Approximately 25% of those with JIA experience ongoing inflammatory arthritis in adulthood.