JIA and RA

When a young person is diagnosed with JIA (aged 16 or under) and their symptoms continue into adulthood, they technically keep this diagnosis for life. We are aware that some people have been told their condition has been ‘reclassified’ as RA when they are an adult, and in some countries, including the US, there isn’t this distinction between RA and certain types of JIA. In recent years adults who have had a diagnosis of JIA before age 16 are now classified as people with the diagnosis – Adult Juvenile Idiopathic Arthritis. 

The word ‘arthritis’ means ‘inflammation of the joints’, so all types of arthritis will have symptoms in common. In JIA, because the different types of JIA themselves vary greatly from one to another, the ways in which they vary from RA are hard to quantify. However, there is one form of JIA which is indeed the junior form of RA. This usually affects girls around secondary school age, involves several smaller joints, symmetrically in the body and the blood tests show the same results as adults with RA.

Juvenile idiopathic arthritis (JIA) is an umbrella term for 7 types of arthritis that may occur in children. Over time this situation may change with each child, some will get better and some may have additional symptoms leading to a firm diagnosis.

Diagnosis of JIA is not exactly the same as diagnosis of RA, but many of the same investigations would be carried out, including testing for inflammatory markers in the blood (ESR and CRP), scans such as X-ray or ultrasound and examination of the joints/discussion of symptoms and any possible family history etc.

JIA can occur at any age in childhood and can vary in severity in the number and type of joints that are affected. Some childrens’ arthritis will get better before the child reaches adulthood, whilst others will continue into adulthood. Symptoms and possible complications will also vary. One such complication is uveitis, inflammation within the eye(s), which occurs in between 10-30% of children with JIA and often carries no symptoms in the early stages. Eye examinations are therefore very important for children with JIA.

Like RA, JIA can often be mistaken for other causes and conditions. In the case of JIA, ‘growing pains’ or injuries might be suspected or a child might not be believed at all when they say they are too tired or in too much pain to do a particular activity. Diagnosis can be even harder in younger children who might not have the speech capabilities to get their symptoms across to their parent or a healthcare professional. Parents, of course, will often just have a sense that their little one is not behaving their usual self, but may not understand why. A GP examining the child may be looking for subtle signs, such as ‘guarding’ which means the child finding ways not to use a specific joint when they walk, stand up or play. Swollen joints may not always be as visible on a young child with their ‘baby fat’, but there can be other signs of swelling, such as heat and a spongy feeling on examination. The immune system’s response in the body, which causes this inflammation, increases blood flow to the area. This can lead to physical changes in a growing child’s skeleton and is the reason why speedy referral to a paediatric rheumatologist is essential.

Not all the medications given in RA are approved for use in JIA, but many are. DMARDs such as methotrexate and biologic DMARDs will therefore be common to both conditions, as are steroids, anti-inflammatories and painkillers, although the doses and the circumstances in which they are given will vary.

Whilst it would not be true to say that most forms JIA is a juvenile form of RA, adult patients with JIA will often find they have a lot in common in terms of symptoms and treatment, to adults with RA. Therefore, even before we set up our JIA service, which primarily focuses on parents of children and on young people with the condition, we have had contact with JIA patients, particularly the adults, who benefit from attending RA groups and discussing life with JIA on RA forums.

Updated: 13/11/2018

Next review: 13/08/2021