Consider this hypothetical scenario: Your daughter exuberantly implores you to watch her doing cartwheels on the lawn and as you turn to look, you notice something odd. Instead of planting her open palms on the ground when she kicks her legs into the air over her head, her hands are tightly clenched into a fist. When you ask her why she doesn't open her hands, you get an unexpected reply -- she can't bend her wrist back far enough to place the palms of her hands on the ground.
This behavior, or something similar, like doing pushups on closed fists, is often the first clue that your child has juvenile idiopathic arthritis, formerly known as juvenile rheumatoid arthritis, or JRA, according to Dr. Katharine Moore, a pediatric rheumatologist in Denver. The word idiopathic means "of unknown origin." One reason the name was changed was to differentiate the pediatric condition from adult RA.
"Many kids (with JIA) have more stiffness than pain," Moore explains. "Adults can readily describe their symptoms to a doctor. Kids often cannot," Moore says, noting that concepts such as stiffness are fairly abstract and can be difficult for a child to describe. Moreover, the child may be so accustomed to joint stiffness that it doesn't seem abnormal.
What Are Juvenile Rheumatoid Arthritis Symptoms?
Parents rarely expect arthritis to affect their kids. Here are possible signs and symptoms:
-- Knee, hand or foot joints that are stiff, swollen or painful.
-- Reddened joints that are warm to the touch.
-- Avoiding use of one or more joints.
-- Reduced appetite, slow growth, too little weight gain.
-- Eye inflammation, visible or found on an eye exam.
-- High fever and rash.
-- Swollen lymph nodes.
These symptoms could signal a number of conditions, including arthritis. Contact your pediatrician if they occur.
What Is Juvenile Rheumatoid Arthritis?
Like adult rheumatoid arthritis, JIA is an inflammatory, autoimmune disorder that develops when the body's immune system begins to attack its own, healthy tissues. Inflammation leads to swelling of the synovium, the lining of the joint, and accumulation of fluid inside the joint (joint effusion).
But the similarity to adult rheumatoid arthritis ends there.
According to the Arthritis Foundation, juvenile idiopathic arthritis is not just a "pint-sized replica" of adult rheumatoid arthritis. Rather, JIA is an umbrella term that encompasses seven different forms of arthritis previously known as juvenile rheumatoid arthritis. Among the seven are oligoarthritis, in which four or fewer joints are involved during the first six months of diagnosis; ankylosing spondylitis, a form of arthritis that primarily affects the spine; enthesitis-related arthritis, which primarily affects the legs and spine; and juvenile psoriatic arthritis, in which the skin disease psoriasis accompanies joint symptoms.
In fact, it is estimated that only about 10 percent of children with juvenile idiopathic arthritis have a disease that closely echoes adult rheumatoid arthritis -- RF-positive polyarticular JIA, which disproportionately affects teenage girls, according to Moore, who is an assistant professor of pediatrics-rheumatology at the University of Colorado School of Medicine.
Serious eye complications can result from JIA. If unidentified and untreated, eye inflammation can lead to cataracts, glaucoma or even blindness, says Dr. Sangeeta Sule, a pediatric rheumatologist and chief of rheumatology at Children's National Health System in the District of Columbia. Fortunately, she says, recently approved medications to treat JIA include some specifically used to treat eye inflammation, which otherwise can be difficult to control.
"The eye inflammation can be completely asymptomatic -- kids may have no outward signs," Sule says. "Unlike the joint disease, which parents can pick up if their child is limping, eye symptoms are harder to identify. So one of the things we stress in rheumatology is these children should go for routine screening with an ophthalmologist, because that's the only way to pick it up."
In particular, the youngest children who have oligoarthritis and who have a positive antinuclear antibody (ANA) blood test are at highest risk for eye complications and need more frequent eye screening, she says.
There appears to be a strong genetic link to JIA for some forms of arthritis, such as enthesitis-related arthritis and psoriatic arthritis.
Another form of JIA that may have some genetic predisposition is systemic JIA (sJIA), which accounts for between 10 to 15 percent of all cases.
"Systemic JIA responds differently than the other types," says Dr. Jay Mehta, the clinical director of the Division of Rheumatology at Children's Hospital of Philadelphia.
Children with sJIA "can have high spiking fevers, a rash that comes and goes, and enlargement of the lymph nodes, liver and spleen," he explains. "Joint pain and inflammation may not develop until a few weeks or months after the fever and rash."
Patients are often quite sick," Mehta says, "and may require hospitalization."
Children with sJIA can respond well to drug therapy, and there is a trend to use biologic medications that block the inflammatory protein interleukin-1 very early in the course of the disease, especially for sicker patients, according to Mehta.
In very young children with JIA, when joint stiffness and pain inhibit daily activities, it can "interfere with meeting developmental milestones," Moore says.
In 2018, the Food and Drug Administration officially approved a subcutaneous version of Actemra, an interleukin-6 (IL-6) blocker drug that was already available in intravenous form. The newer, injectable version is approved for patients ages 2 and older with active systemic or polyarticular pediatric JIA.
Advances continue. "Studies are now being done with JAK (Janus kinase) inhibitors, which are tablets," Sule says. "They were recently approved for adults. Now they're being studied in kids." Tablets could make treatment easier for young patients. "That's one of the biggest barriers for kids -- the idea of giving themselves shots every week or two," she says. "The vials are formulated so they're easy to give. But it's still the concept of giving an injection that can be difficult for parents and their kids."
Juvenile Rheumatoid Arthritis Diagnosis
The diagnosis of juvenile idiopathic arthritis is made based on a physical examination, medical history and lab tests.
"JIA is a clinical diagnosis -- it is based on duration of symptoms (more than six weeks), age of onset (under 16 years), presence of joint effusion, not just joint pain alone and exclusion of alternate causes," Moore explains.
"Sometimes the effusions are obvious just on exam, and sometimes we need to do imaging such as ultrasound or MRI to see them."
Moore notes that most children with JIA have normal labs.
" Inflammation markers in the blood are often normal when joint inflammation is limited to a small number of joints, even if the joints are huge," Moore says.
As with adult rheumatoid arthritis, aggressive treatment is recommended for children and teenagers with juvenile arthritis.
"I always tell families that the reasons we care so much about wanting to be somewhat aggressive in our treatment of JIA are quality of life and to prevent joint damage," Moore explains. "I don't want a child to be a 'tough cookie' now, but then be a 20-year-old who needs a joint replacement."
The goal of treatment is the same as the goal of rheumatoid arthritis treatment -- to calm down the immune response causing the inflammation.
According to Moore, many of the medications used to treat JIA are the same as those used in the treatment of adult rheumatoid arthritis, such as methotrexate and the biologic drugs like etanercept (Enbrel), adalimumab (Humira) and tocilizumab (Actemra).
Parents and children should not fear drug treatment, even though they may have "toxic-sounding names," Moore advises. "These drugs have revolutionized the treatment of JIA and been life-changing for our patients," Moore says.
In addition, they have been studied very extensively to ensure safety and efficacy in kids. "We are very cautious about never wanting the risks [of drug treatment] to outweigh the benefits," she adds.
In general, kids with juvenile idiopathic arthritis cope better than adults with a diagnosis of rheumatoid arthritis, Moore says. "Kids have a strong inner drive to want to run and play and keep up with friends," she says.
However, she notes that kids and teens with chronic or severe disease can have a difficult time dealing with their disease. "They often feel very different from their friends. Activities they once used for coping, such as coloring or running, may be difficult if there is bad joint disease," she says. "When that is the case -- when something is taken away -- it will leave a hole, unless that hole is replaced by something else. So, it is important to fill the hole."
Moore recommends that kids find a project that interests them. "[It] can provide distraction, motivation and self-confidence," she says. "It's important that their identity is not based on what they can't do, but rather is based on what they can do."
Sule offers families encouragement. "In rheumatology now, I tell patients that their quality of life on these new treatments can be excellent," she says. "In the majority of children -- not all -- we can get their arthritis under control with these types of medicines."
One challenge, Sule says, is studies have shown that if medications are stopped too soon, kids may have an arthritis flare, which could worsen their quality of life.
"What studies are now trying to figure out is how long they have to stay on these medicines; whether it's two years, or longer," Sule says. "How long do we need to get the immune system back into remission to keep their arthritis under control?"
Sule is optimistic. "Parents need to know they're not alone, that juvenile idiopathic arthritis is the most common type of rheumatologic disease we see in children," she says. "And that working together, their children can do everything they want to do -- whatever they plan for their lives, they can do."