Juvenile idiopathic arthritis and rheumatoid arthritis are both inflammatory diseases that affect the joints, but they’re separate conditions with unique long-term outlooks.

The most common type of joint condition affecting children and teens is juvenile idiopathic arthritis (JIA). It used to be called juvenile rheumatoid arthritis.

Medical professionals changed the name to avoid confusion with adult rheumatoid arthritis (RA) and to use the term “idiopathic,” which indicates that the exact cause of this condition is not known.

JIA is an autoimmune reaction that occurs when the immune system mistakenly attacks the joints in a child.

JIA affects about 1 in every 1,000 children under 16 years old. It may cause pain and swelling in one or several joints. The symptoms last for at least 6 weeks.

Although there’s no cure for JIA, treatment can help manage symptoms. In some cases, JIA may go into remission.

Types of juvenile idiopathic arthritis:

There are six main types of JIA:

  • Oligoarthritis: The most common type, it affects up to four joints.
  • Polyarthritis: This type affects five or more joints. About 25% of children with JIA have this type, which may develop into RA.
  • Systemic: This type affects joints, organs, and skin throughout the body.
  • Psoriatic arthritis (PsA): Juvenile PsA affects joints and the skin, causing a scaly rash.
  • Enthesitis-related (ERA): More common in boys, ERA affects areas where muscles, tendons, and ligaments attach to bones.
  • Undifferentiated: This type affects at least one joint, but symptoms aren’t always the same as the other types.

While both are types of inflammatory arthritis, JIA is not the same condition as RA.

To receive a JIA diagnosis, a child must be under 16 years old and have inflammation in at least one joint that lasts for more than 6 weeks.

RA causes inflammatory pain in multiple joints in adults. While JIA has six types, RA is a specific condition.

RA symptoms may be chronic and last a lifetime. With treatment, many children with JIA experience periods of remission.

JIA may cause growth problems if the bones close to inflamed joints grow too slowly or quickly. For example, this could result in one leg being shorter than the other. RA doesn’t cause these problems because adult bones are fully formed.

Here’s a quick breakdown of the differences between JIA and RA:

JIARA
affects children younger than 16 years oldaffects adults
6 typessingle condition
may go into remissionmay be chronic and last a lifetime
may cause growth problemsdoes not affect bone development

JIA is more likely to progress into RA for children with rheumatoid factor (RF) positive polyarthritis. This means their blood tested positive for RF.

RF is a protein your immune system produces. RF may attack healthy cells it mistakes for foreign bodies. High RF levels may indicate an autoimmune disease such as RA or JIA.

Both JIA and RA cause joint pain that may worsen after waking up or remaining in one position for a long time. For JIA, the other symptoms may depend on the type of JIA.

Common symptoms affecting all types of JIA, as well as RA, include:

Other symptoms affecting children with JIA may include:

Inflammatory eye conditions, such as uveitis and iritis, occur more commonly with oligoarthritis JIA. Symptoms like eye pain and sensitivity to light need treatment right away since they can lead to vision and eye damage.

With systemic JIA, the lymph nodes may become swollen and inflamed. This swelling can sometimes spread to the internal organs.

Generally, treatment for JIA and RA may include medications, physical and occupational therapy, and lifestyle strategies.

These treatments aim to slow joint inflammation and damage, relieve pain, and improve the quality of life.

JIA treatment may depend on the type and severity.

Medications that treat JIA and RA include:

A doctor may also prescribe physical therapy and occupational therapy. These therapies teach people with JIA or RA ways to improve their quality of life, such as strengthening exercises and how to perform daily tasks.

Some lifestyle strategies, like eating a largely Mediterranean diet and getting regular exercise, may also help people manage their JIA or RA symptoms.

Due to today’s treatments, such as biologic drugs, the outlook for children with JIA has significantly improved, according to the Arthritis Foundation.

A 2017 systematic review found that 7% of children with JIA experienced remission within 18 months and 47% within 10 years.

However, the long-term outlook may depend on the type of JIA.

For example, children with oligoarthritis, the most common type of JIA, have the highest rate of remission and are less likely to have RA as adults.

Children with RF-positive polyarthritis are the least likely to achieve remission. As they get older, their JIA may develop into RA.

The following are answers to some frequently asked questions about JIA.

Can you have juvenile idiopathic arthritis as an adult?

It’s possible to have JIA as an adult.

A 2016 Portuguese study with 426 adults who had received a JIA diagnosis when they were about 10 years old and had arthritis for 22 years found that 95.6% of them had RF-positive polyarthritis.

Researchers concluded that children who received a JIA diagnosis at a younger age had less chance of the condition becoming inactive.

Is juvenile idiopathic arthritis a rheumatic disease?

Yes, JIA is a rheumatic disease.

Like RA and most rheumatic diseases, JIA is an autoimmune disorder where your immune system mistakenly attacks your body’s healthy cells and tissues. This leads to inflammation and degeneration of your healthy cells, including those in your joints.

Does juvenile idiopathic arthritis ever go away?

JIA symptoms may flare for a few weeks or months and then go into remission for some time. While some children may only experience a few flares, others have ongoing symptoms.

Some children with JIA fully recover, or the condition goes into long-term remission.

According to the 2016 study, 56% of people who received a JIA diagnosis as children continued to have it as adults. Their diagnoses are often reclassified from JIA to RA.

Is juvenile idiopathic arthritis hereditary?

Most cases of JIA affect children whose families have no history of the condition.

However, children with a sibling who has JIA are about 12 times more likely to develop the condition than other children.

Children with a family member who has chronic arthritis are also slightly more at risk of developing JIA. Those with a family member who has psoriasis are at more risk of psoriatic JIA.

JIA and RA are different inflammatory arthritis conditions. JIA diagnoses only occur in children younger than 16 years old.

While RA may be a lifelong condition, JIA may go into remission. Treatment for both conditions usually includes medications and physical therapy to prevent joint damage and improve quality of life.

Starting treatment as early as possible may result in a better outcome for children with JIA.