Juvenile idiopathic arthritis (JIA): symptoms, types and treatment

Juvenile idiopathic arthritis is a general name for several kinds of arthritis that begin in children under 16. Leeds Teaching Hospitals explains the words: juvenile means it affects young people, idiopathic means other known causes such as infection in the joint have been ruled out, and arthritis means inflammation of the joints. It causes inflammation in one or more joints for six weeks or longer.

It is an autoimmune condition. Arthritis UK describes the immune system as confused and attacking the body's own healthy tissues by mistake, so the joints become inflamed when they do not need to be. It is different from rheumatoid arthritis, which is usually diagnosed in adults. The charity says the cause is not fully understood, is thought to involve a combination of factors such as genes, and is not something the child or parents have done or caused.

Leeds Teaching Hospitals lists the features of an inflamed joint as swelling, pain, stiffness (especially in the morning) and warmth, and notes that a child may not have all of these in every affected joint. Arthritis UK adds that joints can look puffy and feel warm, and that stiffness is often worse in the morning or after resting. Any joint can be affected, including fingers, wrists, elbows, knees, ankles, feet and hips.

JIA can also cause tiredness, and less commonly fever, rash, loss of appetite and weight loss according to Leeds. Arthritis UK lists blurry vision or dry eyes among possible symptoms. Because children may not complain of pain, parents may first notice limping, reluctance to join in games or stiffness after waking. Symptoms can come and go and may change between joints over time.

• Swollen, warm or stiff joints, especially after sleeping or resting

• Limping or avoiding activities they previously enjoyed

• Unusual tiredness

• Fever or skin rash in some types

• Eye redness, light sensitivity or changes in vision, although eye inflammation often causes no symptoms at all

Arthritis UK describes six subtypes and notes that finding which type a child has is not always easy and the subtype may change over time. The pattern matters because it shapes treatment, the risk of eye inflammation and the outlook.

Arthritis UK says there is no single test for JIA and that it can be difficult to diagnose. Some children have blood tests or scans, but not everyone has the same ones, and a child may see several doctors before the diagnosis is made. The doctors look for symptoms that last six weeks or longer, symptoms that started before the 16th birthday, and signs of other conditions that could cause joint symptoms, which have to be excluded.

Care is usually led by a paediatric rheumatology team, which may include specialist nurses, physiotherapists and occupational therapists. Cambridge University Hospitals notes that blood results such as the antinuclear antibody (ANA) are used to understand eye risk, since uveitis is more common in children who are ANA positive.

Uveitis is inflammation inside the eye. Cambridge University Hospitals says between 10 and 20 per cent of children and young people with JIA develop it, and that early and regular screening is vital because children often do not notice any problems and there is not always anything to see on the outside of the eye. Leeds says it usually has no symptoms in young children and a doctor cannot tell by simply looking, so regular check-ups with an ophthalmologist are very important to avoid permanent vision loss.

Cambridge explains that screening is done in a clinic with a slit lamp, by an ophthalmologist or occasionally a specially trained orthoptist, and that high street opticians cannot examine the eye in enough detail. The first eye examination should take place within six weeks of the JIA diagnosis, and later checks are arranged individually. Uveitis is more common in girls under seven (especially under four), in oligoarticular JIA and in children who are ANA positive, but it cannot be predicted, so every child is screened.

If found, treatment may include steroid eye drops, pupil-dilating drops and, when drops are not enough, tablets or injections that suppress the immune response, decided jointly by ophthalmologist and rheumatologist. Untreated uveitis can cause cataracts, glaucoma and permanent loss of vision according to Cambridge.

Treatment is tailored to the child. Leeds lists the main approaches: medicines to control inflammation, steroid joint injections, exercises to keep joints moving and muscles strong, and pain management strategies. The goals are to return the child to normal activities, reduce pain, prevent joint damage and keep joints working as well as possible.

Arthritis UK lists painkillers such as paracetamol, non-steroidal anti-inflammatory drugs such as ibuprofen, disease-modifying anti-rheumatic drugs (DMARDs) such as methotrexate, steroids, and biologics and biosimilars, given as tablets or injections. It says it can take time to find what works and that the child should tell the team if a treatment is not helping because other options exist. Physiotherapists provide exercise plans, and occupational therapists help with everyday activities at home and school. All of these are prescribed and monitored by the specialist team, not started at home.

Arthritis UK says there is no cure but many treatments, and that most people with JIA can expect long and full lives, although some types such as systemic JIA can cause serious complications, which is why regular treatment and monitoring matter. It says you do not grow out of JIA but you can go into remission, with periods when symptoms are absent or controlled, and that some children have no symptoms as adults. Leeds notes that with modern treatments most JIA can be controlled and most long-term consequences avoided.

Day to day, the condition can fluctuate. Arthritis UK describes flare-ups when symptoms temporarily worsen and advises contacting the healthcare team, who may want to consider different treatments. It also highlights school adjustments, tiredness, sleep problems and mental health: young people with arthritis are more likely to struggle with mood, so a counsellor or psychologist can help, and your school or healthcare team may be able to refer. The charity offers guidance for parents and for schools.

A GP usually refers a child with suspected persistent joint swelling to a paediatric rheumatology service, and the team then coordinates treatment, eye screening and therapy. Wait times for specialist assessment vary by area. Some families also choose to see a private paediatric rheumatologist; the same principles apply, and shared care with the NHS eye screening programme is still important. Seek urgent help via NHS 111 or A&E for a painful red eye, sudden vision change, or a child who is feverish and unwell with a very painful swollen joint.