What Is Juvenile Idiopathic Arthritis (JIA)? Symptoms, Causes, Diagnosis, and Treatment

Medically Reviewed
child sitting in bed
About 1 child in 1,000 has some form of chronic arthritis or juvenile idiopathic arthritis. It can be challenging, but it's treatable.  Catherine Falls/Getty Images
Kids and teenagers up to age 16 who experience prolonged swollen or painful joints anywhere in the body are typically diagnosed with juvenile idiopathic arthritis. While the term “juvenile rheumatoid arthritis” has been used in the past, today most cases of inflammatory arthritis are referred to as juvenile idiopathic arthritis (JIA).

JIA is the most common form of arthritis that affects kids and teens; "idiopathic" means it’s unknown exactly what is causing the problem, according to the Arthritis Foundation.

There are several different forms of JIA, but the most common are oligoarticular arthritis, which affects up to four joints in the body, and polyarticular, which affects more than four joints, says Anjali Sura, MD, an assistant professor of pediatrics at SUNY Upstate University Hospital in Syracuse, New York. There is overlap among the types of JIA, along with multiple subtypes, and lots of debate about new classifications, says Jay Mehta, MD, an associate professor of clinical pediatrics at the University of Pennsylvania Perelman School of Medicine and the fellowship director at Children’s Hospital of Philadelphia.

Currently, other types of JIA include:

  • Systemic, which affects the entire body, including the joints, the skin, and internal organs, according to the Arthritis Foundation

  • Juvenile enthesitis-related arthritis (ERA), which affects the tendons and ligaments attached to the bone, per AboutKidsHealth

  • Psoriatic arthritis, which affects the joints and features a rash on parts of the skin, according to the Arthritis Foundation

  • Undifferentiated, which isn’t clearly linked to one type but has some form of joint swelling and/or pain

Signs and Symptoms of Juvenile Idiopathic Arthritis

According to the Centers for Disease Control and Prevention (CDC), symptoms may appear, then disappear.

When symptoms are active, they are called flares. When symptoms quiet down, they are in remission. Symptoms can include:
  • Joint swelling that lasts for days or weeks
  • Morning stiffness
  • A limp or pain that is worse in the morning but improves as the day goes on
  • Loss of range of motion in a joint
  • Joints affected can include knee, fingers, wrists, ankles, and elbows.
  • Other signs of JIA may include fever, rash, fatigue, a loss of appetite, eye inflammation, or trouble with daily tasks such as walking, dressing, or playing, per the CDC.

Causes and Risk Factors of Juvenile Idiopathic Arthritis

There’s no solid answer right now about why JIA develops, experts say. Some families develop a collection of autoimmune conditions, though not usually the same ones, and JIA can be one of those diagnoses, says Dr. Sura. Other families have no history of any autoimmune disease when it is diagnosed.

Some believe JIA happens as a combination of genetics and some environmental triggers, says Dr. Mehta, “but we don’t know what they are. There are some genes that are identified as having a potential role, but not everyone with those genes gets arthritis, and not all with arthritis have those genes.”

How Is Juvenile Idiopathic Arthritis Diagnosed?

It may not be obvious that your child has an issue, as there is no blood test that confirms JIA, swelling may not be evident, and some kids won’t ever complain about being in pain, according to the American College of Rheumatology.

Kids are typically diagnosed by a pediatrician/primary care physician or a rheumatologist, following observed joint swelling, pain, stiffness, or a difference in a joint’s range of motion that doesn’t go away after time, isn’t related to exercise or a particular activity, and is worse in the morning upon waking up. It can also be seen when a child limps, as JIA can affect the knee joint in one leg, which then shortens leg length on one side, note Sura and Mehta.

JIA is diagnosed typically with magnetic resonance imaging (MRI) or ultrasound imaging, as well as testing for other diagnoses, such as Lyme disease, to rule out other causes as well as other forms of arthritis. Effective treatment depends on an accurate diagnosis.

Prognosis of Juvenile Idiopathic Arthritis

With the availability of JIA medication known as biologics, the prognosis for people living with the condition is excellent, says Sura. With the right treatment, people with JIA can expect to have a full quality of life and maintain a full range of joint motion. Before these drugs became available in the early 2000s, people with JIA could experience permanent disability and/or needed joint replacement surgery.

Medication to treat JIA can have side effects, so ongoing bloodwork may be needed to ensure, for example, that liver function remains healthy. Most drugs to treat JIA are immunosuppressive, says Sura, so infection risk can be higher than someone not taking these drugs. “I haven’t seen any serious infections among my patients, but they may have a cold that lasts one day longer,” she says. “And with the pandemic and the registry of JIA patients being followed, they don’t seem to have worse rates of COVID or more severe cases of it.”

Early treatment, which can include exercise and occupational and physical therapy as well as medication, can help improve or maintain physical function, reduce or prevent pain, and protect against further joint damage, according to the Cleveland Clinic.

A study published in July 2021 in the journal Arthritis Care & Research found that MRI in kids with JIA considered to be in remission (through a lack of physical symptoms, clinical exams, and proteins measured through blood tests) instead found signs of inflammation in a layer of tissue in the joint, along with bone marrow swelling that could predict a future disease flare. The study shows that ongoing imaging may be helpful in predicting who may experience future joint problems despite JIA seeming to be in remission.

Duration of Juvenile Idiopathic Arthritis

While some kids who are diagnosed with JIA grow out of it, others go into remission, where symptoms go away for a long period of time, while some live with ongoing issues such as rashes, fever, slow growth, osteoporosis, and worsening arthritis. Rarely, JIA can affect the organs and cause issues with the endocrine system, kidneys, or heart.

It depends on the type and age of person when diagnosed with JIA, but “in general, about one-third of all kids outgrow it, one-third go into remission for a few years, and one-third have the more chronic form where they flare and still have juvenile arthritis into adulthood,” says Sura.

A blood test can indicate if a person has rheumatoid factor in the blood – rheumatoid factors are proteins that indicate the immune system is fighting against something in the body, according to MedlinePlus.

People with rheumatoid factor are more likely to have chronic arthritis, while those without it have a better chance of outgrowing the disease. An RF blood test can be done in conjunction with a CCP blood test; this is another test that looks for proteins in the blood, which indicate whether a person will develop rheumatoid arthritis.

Treatment and Medication Options for Juvenile Idiopathic Arthritis

According to the Arthritis Foundation, JIA treatments and drugs aim to:

  • Stop or reduce joint inflammation, pain, or other symptoms
  • Prevent or stop joint or organ damage
  • Preserve function, mobility, and quality of life
  • Help people get to remission
Treatment guidelines issued by the American College of Rheumatology (ACR) in early 2022 recognize that each person living with JIA is different, that treatments may vary based on the specific type of JIA, and that patients, caregivers, and providers should work together to determine the best course of action to attain the highest quality of life.

Medication Options

With mild JIA symptoms, pain relievers and/or nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (Advil, Motrin) or naproxen (Aleve) are used to help patients feel better physically. Sura says that in about 30 to 40 percent of her patients, this treatment is sufficient. These drugs, however, don’t treat underlying joint damage if it exists.

Some patients with certain forms of JIA may also benefit from a short course of injected corticosteroid drugs. But if these treatments don’t stop joint pain or swelling or joint function does not improve, or if you have a form of JIA that is best treated with stronger medication, the next step is to choose a disease-modifying antirheumatic drug, known as a DMARD. Conventional DMARDs work to suppress the overall immune system, while biologic DMARDs target specific parts of the immune process. Either way, DMARDs can help slow or stop JIA’s joint inflammation and potential joint damage.

DMARDs such as methotrexate can cause some nausea or fatigue, and depending on the medication used, patients are prescribed a daily multivitamin and have their blood counts and liver monitored to watch out for side effects. Mehta says most of his patients do well on methotrexate.

Those who need more treatment try biologic drugs. Biologics for JIA include adalimumab (Humira), tofacitinib (Xeljanz, Xeljanz XR)infliximab (Remicade), and etanercept (Enbrel). These drugs are typically injected or infused, although the pill Xeljanz (tofacitinib) was approved by the U.S. Food and Drug Administration (FDA) for kids to take to treat polyarticular JIA in 2020.

If JIA is still not controlled after using these common biologics, there are other biologic options to try, says Sura. A study of kids with systemic JIA published in August 2021 in the journal Rheumatology found that the drug Ilaris (canakinumab) was helpful for the majority of participants.

The growth of DMARDs, particularly biologics, has helped change treatment guidelines for those with JIA. Previously, some people with JIA began taking high doses of steroids at an early age. This led to weakened bones, osteoporosis, and suppressed growth. Starting JIA treatment with biologic DMARDs helps avoid such complications.

Alternative and Complementary Therapies

Research on children with JIA is lacking; most studies on alternative and complementary ways to help people with JIA are done on adults with osteoarthritis or rheumatoid arthritis and don’t necessarily apply to kids with JIA, notes the Arthritis Foundation.

In early 2022, however, the American College of Rheumatology published guidelines for nondrug treatments for all people living with JIA. These cover physical and occupational therapy as needed, eating a well-balanced and healthy diet as it relates to one’s age, and lab tests both before starting and during treatment with new JIA medication to determine if the drugs are effective. The ACR guidance also urges people with JIA and the people they live with to stay up-to-date on all recommended vaccinations, including annual flu shots and ongoing COVID-19 shots as directed by public health experts.

Exercise, yoga, massage, acupuncture, diets with blueberry juice, turmeric, fish oil, and/or avoiding gluten are all possible complementary treatments for JIA, according to the Arthritis Foundation.

“What I tell families is that they are welcome to try diet interventions, but there are no randomized control studies for juvenile idiopathic arthritis,” says Mehta. “If something works, I’m super happy for them, but it has to be a complement to the standard-of-care medicines.” In other words, such therapies help when they supplement — but never replace — drug treatment.

Always speak with your child’s physician about what methods you may incorporate and in what capacity.

Complications of Juvenile Idiopathic Arthritis

With the appropriate medication and other treatment, JIA can be well managed. When it is not, joint damage can occur. This can look like:

  • A leg length discrepancy, based on joint issues in the knee. This can be treated with a heel lift in the shoe, notes Sura.
  • Muscle atrophy around the knee or other joints. Physical therapy can help build those muscles back up, per Sura and Mehta.
  • Eye inflammation, known as uveitis, or other eye problems such as glaucoma or cataracts

  • Whole-body inflammation. With systemic JIA, a person can develop macrophage activation syndrome, which can trigger serious problems such as a low blood count, organ failure, and death, if not properly treated ahead of time, notes the Arthritis Foundation.

  • Osteoporosis and/or growth problems, according to AboutKidsHealth

Who Has Juvenile Idiopathic Arthritis?

According to the American College of Rheumatology, about 300,000 children, or 1 in 1,000, have JIA in the United States. It is typically diagnosed in kids between the ages of 6 months to 16 years old.

Related Conditions of Juvenile Idiopathic Arthritis

As an autoimmune condition, JIA occurs when the body wrongly attacks a normal part of itself thinking it’s being threatened. Similarly, people with JIA can experience other autoimmune conditions. They include:

  • Uveitis, or inflammation of the eye. As it may develop without pain and can threaten vision, Sura recommends that all people with JIA see an ophthalmologist to have ongoing dilated eye exams, where the back of the eye can be closely observed with a special machine known as a slit lamp.
  • Psoriasis. This skin condition can coexist with juvenile arthritis and is known as psoriatic juvenile idiopathic arthritis, or psoriasis-related JIA, according to the Genetic and Rare Diseases Information Center.

  • Inflammatory bowel disease (IBS), which includes gastrointestinal problems such as Crohn’s disease and ulcerative colitis. Per the Arthritis Foundation, it is most common in the form of JIA known as juvenile enthesitis-related arthritis.

Resources We Love

The Arthritis Foundation

This website offers good information about juvenile idiopathic arthritis and how parents can talk to their children about it. The Arthritis Foundation also offers information about attending school and college with JIA and hosts summer camps and support groups around the United States and virtually where kids with juvenile arthritis can meet and interact with peers. They also feature a one-on-one helpline (online or phone) staffed by a licensed, clinical social worker who can offer support.

Taking Charge: Managing JIA Online

Aimed at teens who need to take more responsibility for their juvenile idiopathic arthritis as they grow up, this site — part of AboutKidsHealth and backed with medical guidance by Toronto’s The Hospital for Sick Children — gives a full look at what JIA is, what is needed to stay healthy while living with it, traditional and complementary forms of treatment, and other information for teens to take ownership of their condition as they head into adulthood.

American College of Rheumatology

While this a physician professional organization, it offers one-page information sheets about different arthritis medication and conditions that may be helpful for families of people with JIA.

Your Pediatric Rheumatologist

Speak with your child’s physician about what resources they’d recommend. “I think all of us really love what we do when we partner with families on this journey,” says Mehta. For his patients and their families, he says, “I’m with you and I will do my best to figure out what to do to get you answers.”

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