Juvenile Idiopathic Arthritis (JIA)
Nurses, health visitors, school health advisors and practice nurses are often the first professionals to see a child with early symptoms of arthritis. Early recognition and timely referral are essential to reduce the risk of joint damage, growth disturbance and long-term disability.
Juvenile Idiopathic Arthritis (JIA) is an umbrella term describing a group of chronic inflammatory joint conditions in children. Each subtype has different clinical features, but JIA is defined as arthritis affecting one or more joints, lasting longer than 6 weeks, with onset before 16 years of age.
JIA is the most common cause of chronic arthritis in children in the UK, affecting around 1 in 1,000 children (a similar frequency to childhood epilepsy), with approximately 12,000 children affected nationally. In some parts of the world, other conditions such as Lyme disease are more common causes of childhood arthritis.
There is no single test that confirms or excludes JIA. Diagnosis is based on the presence and persistence of arthritis and the careful exclusion of other causes through history, examination and appropriate investigations.
The differential diagnosis is broad, ranging from benign conditions such as hypermobility to serious causes including infection, malignancy (for example leukaemia or solid tumours), and non-accidental injury. The presence of red flag features such as fever, weight loss, night pain or bone tenderness should prompt urgent assessment in secondary care.
Assessing the Child
Assessment of children differs from adults. Younger children may not be able to describe pain clearly, and the history is often provided by parents, carers or teachers. Early symptoms may be vague, for example: 'My child is not quite right', 'My child is limping', or 'They don’t want to play as much as usual'. Findings must be interpreted in the context of normal growth and development.
Features Suggesting Inflammatory Disease
- Change in behaviour, such as irritability, clinginess or reluctance to play
- Avoidance of previously enjoyed activities, including play or sport
- Regression of motor skills, such as walking, running or handwriting
- Morning stiffness or stiffness after rest ('gelling'), where the child is slow to get moving after sleep or inactivity
- Impact on Growth and Development
If untreated, inflammatory arthritis can affect bone growth around the involved joint. For example, knee arthritis may lead to leg length inequality due to increased blood flow stimulating bone growth, followed later by early closure of the growth plate and shortening of the limb.
Abnormal growth can also affect the fingers, toes and jaw, leading to difficulties with hand function and fine motor skills, walking or fitting shoes comfortably, and eating and chewing. Early recognition and treatment are therefore essential to protect joint function and normal development.
