Juvenile Idiopathic Arthritis
What is juvenile idiopathic arthritis?
Juvenile idiopathic arthritis (JIA) is the most common type of arthritis that affects children. It used to be known as juvenile rheumatoid arthritis, but the name was recently changed to reflect the differences between childhood arthritis and adult forms of rheumatoid arthritis.
JIA is a chronic (long-lasting) disease that can affect joints in any part of the body. In this disease, the immune system mistakenly targets the synovium, the tissue that lines the inside of the joint. The synovium responds by making excess fluid (synovial fluid), which leads to swelling, pain and stiffness. The synovium and inflammation process can spread to the surrounding tissues, eventually damaging cartilage and bone. Other areas of the body, especially the eyes, also may be affected by the inflammation. Without treatment, JIA can interfere with a child’s normal growth and development.
There are several main subtypes of JIA, which are based on symptoms and the number of joints involved.
- Systemic arthritis— Also called Still’s disease, this type occurs in about 10 to 20 percent of children with JIA. A systemic illness is one that can affect the entire person or many body systems. Systemic JIA usually causes a high fever and a rash, which most often appears on the trunk, arms and legs. It also can affect internal organs, such as the heart, liver, spleen and lymph nodes. This type of JIA affects boys and girls equally and rarely affects the eyes.
- Oligoarthritis— This type of JIA affects fewer than 5 joints in the first 6 months of disease, most often the knee, ankle and wrist joints. It also can cause inflammation of the eye (often the iris, the colored area of the eye), called uveitis, iridocyclitis or iritis. About half of all children with JIA have this type, and it is more common in girls than in boys. Many children will outgrow this type of arthritis by adulthood. In some children it may spread to eventually involve more joints.
- Polyarthritis— This type of JIA affects 5 or more joints in the first 6 months, often the same joints on each side of the body. Polyarthritis can also affect the neck and jaw joints as well as small joints, such as those in the hands and feet. It is more common in girls than in boys.
- Psoriatic arthritis— This type of arthritis affects children who have arthritis with the rash of psoriasis. Children frequently have nail changes that look like pitting. The arthritis can precede the rash by many years or vice versa.
- Enthesitis-related arthritis— This type of arthritis often affects the spine, hips and enthesis (attachment point of tendons to bones) and occurs mainly in boys older than 8 years. The eyes are often affected in this type of arthritis. There is often a family history of arthritis of the back (spodylitis) in male relatives.
What are the symptoms of JIA?
Symptoms vary depending on the type of JIA and may include:
- Morning stiffness
- Pain, swelling and tenderness in the joints
- Limping (younger children may not be able to perform motor activities that they recently learned.)
- Weight loss
- Fatigue or irritability
- Eye redness, eye pain, and blurred vision
What causes JIA?
The exact cause of JIA is not known. However, researchers are studying several factors that may be involved, alone or in combination, in triggering the inflammatory reaction seen in JIA. These factors include genetics, infection, and environmental factors that influence the immune system. JIA, however, is not a hereditary disease like cystic fibrosis, for example.
How common is JIA?
JIA is the most common type of arthritis in children. It affects about 1 in 1,000 children, or about 300,000 children in the United States.
How is JIA diagnosed?
There are no tests that specifically diagnose JIA. Rather, JIA is a diagnosis of exclusion, which means the doctor works to rule out other causes of arthritis and other diseases as the cause of the symptoms.
In making a diagnosis of JIA, the doctor usually begins with a complete medical history that includes a description of symptoms, and a complete physical examination. Imaging techniques such as X-rays or magnetic resonance imaging (MRI) can sometimes show the condition of the joints. Laboratory tests on blood, urine, and/or joint fluid may be helpful in determining the type of arthritis. These include tests to determine the degree of inflammation, antinuclear antibody (ANA), and rheumatoid factor. These tests also can help rule out other diseases — such as an infection, bone disorder, or cancer — or an injury as the cause of your child’s symptoms.
How is JIA treated?
The goals of treatment are to relieve pain, reduce swelling, increase joint mobility and strength, and prevent joint damage and complications. Treatment generally includes medications and exercise.
Medications used to treat JIA include:
- Nonsteroidal anti-inflammatory drugs (NSAIDs)— These medicines provide pain relief and reduce swelling, but do not affect the course or prognosis of JIA. Some are available over the counter and others require a prescription. Examples include ibuprofen and naproxen. These medicines can cause nausea and stomach upset in some people and need to be taken with food.
- Corticosteroids (steroids)— In patients with oligoarthritis or in patients with very painful/ swollen joints with other types of JIA, these medications are very effective when given as an injection (shot) into the affected joint. If a child is younger or if several joints are injected, sedation is often used. In patients with more severe widespread disease, these medications occasionally need to be given by mouth as a pill. These medicines, when given by mouth, are effective, but can have serious side effects—including weakened bones —especially when used for long periods. Doctors generally try to avoid using steroids in children because they can interfere with a child’s normal growth.
- Disease-modifying anti-rheumatic drugs (DMARDs)— These medications work by changing, or modifying, the actual disease process in arthritis. The aim of DMARD therapy is to prevent bone and joint destruction by suppressing the immune system’s attack on the joints. Methotrexate (Rheumatrex®, Trexall®) is the DMARD most often used to treat JIA. Other medications used include sulfasalazine (Azulfidine®) and leflunomide (Arava®).
- Biological modifying agents— Biological agents are medications that directly target molecules or proteins in the immune system that are responsible for causing the inflammation. They are given by injection or by infusion and are used to treat children with more severe arthritis that is not responsive to other medications. Etanercept (Enbrel®), infliximab (Remicade®), adalimumab (Humira®), abatacept (Orencia®) and anakinra (Kineret®) are examples of this type of medication.
Exercise and physical and occupational therapy can help reduce pain, maintain muscle tone, improve mobility (ability to move) and prevent permanent handicaps. In some cases, splints or braces also may be used to help protect the joints as the child grows. Special accommodations with schools may be needed to adjust for children with limitations from their arthritis. The Americans with Disabilities Act (“504” plan) can help facilitate these issues.
What is the outlook for people with JIA?
JIA affects each child differently. For some, the disease is mild and easy to control, with only one or two joints affected. For others, JIA may involve many joints and the symptoms may be more severe and may last longer. With the help of modern medical, physical, and occupational therapy, it is possible to achieve good control of the arthritis, prevent joint damage, and enable normal or near-normal function for most patients. Early detection and treatment may help to control inflammation, prevent joint damage, and maintain your child’s ability to function.
What complications are associated with JIA?
If it is untreated, JIA can lead to:
- Loss of vision or decreased vision due to iridocyclitis/uveitis
- Permanent damage to joints
- Chronic arthritis and disability (loss of function)
- Interference with a child’s bones and growth
- Inflammation of the membranes surrounding the heart (pericarditis) or lungs (pleuritis)
How the eye works
Although it might not seem possible, a disease that affects the joints can sometimes also affect the eyes.
Children with juvenile idiopathic (formerly called rheumatoid) arthritis (JIA) can develop eye problems either as a result of the disease itself or, rarely, as a side effect of some medicines.
This information will help you learn more about how JIA might affect your child’s eyes.
The eye functions in the same way as the inner workings of a camera.
The front of the eye admits light rays through the cornea, the pupil (the middle of the iris that determines how much light enters the eye), and a transparent fluid known as the aqueous humor in the anterior chamber.
Next, the lens focuses that light through a clear gel-like substance called the vitreous humor, onto the retina. The retina is a thin layer of tissue that makes up the inner lining of the back of the eye.
The retina works like film in a camera, transforming light into images. It converts the light rays to impulses that travel along the optic nerve to the brain. The brain integrates the images sent from both eyes and interprets them as a single, three-dimensional image, allowing us to perceive depth and distance.
If any of the parts of the eye become damaged, changes in eyesight can occur.
What are some common eye problems that might affect children with JIA?
Uveitis is the most common eye problem that can develop in children with JIA. Uveitis is an inflammation of inner parts of the eye. The uvea consists of the iris (the colored portion of the eye), the ciliary body (which produces fluid inside the eye and controls the movement of the lens) and the choroid (which lines the eyeball from the iris all the way around the eye).
Uveitis might also be known as iritis or iridocyclitis, depending on which part of the eye is affected by inflammation.
If the inflammation is not detected and treated early, scarring and vision problems can occur. Glaucoma, cataracts, and permanent visual damage (including blindness) are all complications that could result from severe uveitis.
Uveitis can occur up to one year before, at the same time as, or up to 15 years after JIA is diagnosed. It can also occur several years after JIA is in remission (the disease is not active).
The severity of the child’s joint disease does not determine how serious the uveitis might be. However, eye problems are more common in children with oligoarthritis (less than five joints with arthritis in the first 6 months of disease). Eye problems are also more likely if your child has a positive blood test for antinuclear antibodies (ANA). They are most likely to occur in female toddlers.
How will I know if my child is developing eye problems?
Because eye inflammation usually is not painful and the eyes are usually not red (“pink”), most children with JIA who develop eye problems do not have any symptoms.
Rarely, children might complain of light bothering their eyes or blurred vision. Sometimes your child’s eyes might look red or cloudy. However, these symptoms usually develop so slowly that permanent eye damage can occur before any visual difficulties are noticed.
In order to detect eye problems and prevent them from causing damage, your rheumatologist will schedule frequent appointments with a pediatric ophthalmologist.
What is an ophthalmologist?
An ophthalmologist is a medical doctor who specializes in diagnosing and treating eye diseases. An ophthalmologist is different than an optometrist, who does not prescribe treatment in many states.
What happens during an ophthalmologist appointment?
The eye exam performed by the ophthalmologist is painless and lasts several minutes. Be sure to tell the ophthalmologist about the medicines your child is taking. (Your rheumatologist can tell you the names of the medicines, the dosages, and why they have been prescribed.)
Prior to the eye exam, the ophthalmologist will put drops in your child’s eyes (which might burn a little) to make the pupils bigger (dilate). Dilating your child’s eyes helps the doctor clearly view the inside of the eyes.
To detect eye inflammation, the ophthalmologist uses a special microscope called a slit lamp. The machine shines a thin beam of light into one eye at a time so the doctor can view the inside of the eyes.
A visual field exam might also be performed to detect vision changes.
How can eye problems be prevented?
Carefully follow your health care provider’s medicine guidelines and keep all your scheduled appointments with your rheumatologist and ophthalmologist, even if you don’t think your child has eye problems or if the JIA is less active.
How often should my child have eye examinations?
The frequency of your child’s eye exams will depend on the type of JIA he or she has, how long your child has had arthritis, and what medicines have been prescribed to treat it.
Because uveitis is more common in children with certain types of JIA, such as oligoarthritis, or in polyarthritis with a positive ANA, more frequent eye examinations (every three to four months) might be recommended. Children with polyarthritis (when ANA is negative) require an examination every 6 months and patients with systemic JIA usually need an ophthalmologist examination every 12 months. Eye exams should continue after your child’s arthritis goes into remission.
Ask your rheumatologist and ophthalmologist how often your child’s eye exams should be scheduled and follow their recommendations. If eye problems are detected, more frequent examinations will be necessary.
How can eye problems be treated?
If eye problems occur, your rheumatologist and ophthalmologist will discuss ways to treat them to prevent permanent eye damage.
If uveitis is diagnosed, different types of eye drops might be prescribed. Eye drops to dilate the eyes may be prescribed in order to keep the pupils open and help prevent scarring.
Steroid (cortisone) drops might be prescribed to reduce swelling and decrease inflammation. However, long-term use of steroid eye drops can have significant side effects such as glaucoma and cataracts.
If eye drops are not effective in decreasing the inflammation, oral steroids (taken by mouth) might be prescribed. Oral or injectable methotrexate is now often used to treat significant eye inflammation so the long-term side effects of steroids can be avoided. In cases of severe uveitis, new “biologic modifying medicines,” such as infliximab (Remicade®) or adalimumab (Humira®) may be used.