Signs parents may notice
- Swelling in one or more joints, often the knee, ankle or wrist
- Morning stiffness that eases as the day goes on
- Limping, especially after waking or after a nap
- Reluctance to walk, write, play or use a hand or leg normally
- Joints that feel warm or look puffy, sometimes without much pain
- In some types, daily spiking fever with a pink rash that comes and goes
Tests that may be used
- Careful joint examination (the most important step)
- Blood tests such as CBC, ESR and CRP
- ANA, rheumatoid factor (RF) and anti-CCP antibodies, HLA-B27 in some children
- Ultrasound, X-ray or MRI of affected joints when needed
- Eye examination with a slit lamp to check for uveitis
What is juvenile idiopathic arthritis?
Juvenile idiopathic arthritis (JIA) is the most common type of long-term arthritis in children. “Juvenile” means it starts before the age of 16, and “idiopathic” means the exact cause is not known. In JIA, the immune system, which normally protects the body from infection, mistakenly causes inflammation in the lining of the joints. This leads to swelling, stiffness and sometimes pain.
JIA is diagnosed when joint swelling has lasted for at least six weeks and other causes, such as infection or injury, have been ruled out. It is not caused by anything a parent did or did not do, and it is not contagious.
Types of JIA
There are several types of JIA. Knowing the type helps guide treatment and follow-up.
- Oligoarticular JIA: four or fewer joints affected, often the knees or ankles. This group has a higher chance of silent eye inflammation (uveitis).
- Polyarticular JIA: five or more joints affected, often including the small joints of the hands and feet.
- Systemic JIA: arthritis together with daily high fevers, a rash and sometimes enlarged glands, liver or spleen.
- Enthesitis-related arthritis: arthritis along with pain where tendons attach to bone, such as the heel; it may involve the lower back.
- Psoriatic arthritis: arthritis with psoriasis, or with nail changes or a family history of psoriasis.
How is JIA diagnosed?
There is no single blood test for JIA. The diagnosis is made mainly from a careful history and a thorough examination of all the joints. Blood tests help look for inflammation, rule out other conditions and identify the type of JIA. Imaging such as ultrasound can show inflammation inside a joint, and an eye examination is part of the initial assessment.
How is JIA treated?
The aim of treatment is to control inflammation, relieve pain, protect the joints and help your child live a full, active life. Treatment is tailored to the type of JIA, the number of joints involved and how your child responds.
- Anti-inflammatory medicines (NSAIDs) help with pain and stiffness.
- Joint injections: a steroid injection directly into an inflamed joint can settle swelling quickly, often for many months.
- Disease-modifying medicines (DMARDs) such as methotrexate reduce the immune system’s attack on the joints over time.
- Biological therapies target specific parts of the immune system. They are considered when other treatments have not controlled the arthritis, or for certain types of JIA.
- Physiotherapy and exercise keep joints moving and muscles strong.
Your child will be monitored with regular check-ups, blood tests to check that medicines are safe, and eye examinations.
When to see a pediatric rheumatologist
If your child has joint swelling, morning stiffness or a limp that lasts more than a few weeks, or a fever that keeps returning with a rash or joint pain, ask your child’s doctor whether a pediatric rheumatology opinion would help. Early diagnosis and treatment can help prevent long-term joint damage.
Treatment options that may be considered
- Anti-inflammatory medicines (NSAIDs)
- Intra-articular steroid injections
- Methotrexate and other DMARDs
- Biological therapies when needed
- Short courses of steroids in selected situations
- Physiotherapy and exercise
- Regular eye screening
When to seek medical help urgently
- High fever with drowsiness, a new rash, bleeding or bruising, especially in a child with systemic JIA
- A single hot, very painful joint with fever, which may be an infection
- Sudden eye pain, redness or blurred vision
Questions parents often ask
Will my child grow out of JIA?
It is difficult to predict for an individual child. Many children, particularly those with only a few joints involved, reach a stage where the arthritis is inactive and medicines can gradually be reduced or stopped. Others need treatment for longer. Regular follow-up helps adjust treatment as your child grows.
Can my child play sports and go to school?
Yes. Staying active is encouraged and helps keep joints and muscles strong. During a flare some activities may need to be adjusted for a short time. Your child's doctor and physiotherapist can advise on what is suitable.
Is methotrexate the same as cancer chemotherapy?
Methotrexate is used in much higher doses in cancer care. For JIA it is given in a low dose once a week to calm the immune system. It is generally well tolerated, and regular blood tests are done to check for side effects.
Why does my child need eye check-ups if their eyes look normal?
Some children with JIA develop inflammation inside the eye (uveitis) that causes no redness or pain at first. Regular eye examinations by an ophthalmologist can pick it up early, before it affects vision.
Can my child have vaccines while on treatment?
Most inactivated vaccines can be given safely. Some live vaccines may need to be avoided or timed carefully with certain medicines. Ideally, vaccinations are reviewed before starting treatment.
Related guides for parents
This page is general information and not a substitute for a consultation. Every child is different, and the right treatment depends on an individual assessment. Please do not start, stop or change any medicine without speaking to your child's doctor.