US Pharm. 2018;43(5):13-14.

An Immune Malfunction

Juvenile idiopathic arthritis (JIA) is an autoimmune disease that occurs in children between the ages of 6 and 16 years. It develops when the immune system malfunctions and attacks healthy joints, leading to inflammation and joint damage. The exact cause of JIA is not known, although a genetic predisposition is the suspected as the trigger. JIA, previously called juvenile rheumatoid arthritis, affects approximately 300,000 children in the United States. There are three subtypes of JIA differentiated by the number of joints affected and the extent of internal organ involvement. Although there is no cure for JIA, treatment can slow its progression and reduce damage.

Fingers and Toes Affected First

The early symptoms of JIA include warm, tender, and swollen joints at the bases of the fingers and toes, and sometimes the knees. As the disease progresses, it affects more joints in the body. Joint stiffness in the morning and after inactivity, fever, fatigue, and weight loss can also occur. A pattern of symptom remission and flare-ups is common in those diagnosed with JIA.

There are no specific tests that can identify JIA. Instead, for diagnosis, physicians rely on a combination of physical examination, family medical history, and a variety of blood tests. When a primary healthcare provider suspects JIA, this usually prompts a referral for an evaluation by a pediatric rheumatologist, a physician who specializes in musculoskeletal and autoimmune diseases in children.

There are three major types of JIA—oligoarticular, polyarticular, and systemic. About 50% of children have oligoarticular JIA, which involves fewer than five of the smaller joints in the wrist or knees. Polyarticular JIA affects five or more joints of any size in the arms, legs, and jaw and accounts for 20% to 30% of cases. Systemic JIA, which occurs in about 10% of children, starts with a high fever and rash and can affect the heart, liver, spleen, and lymph nodes. Joint involvement takes months to years to occur.

Treatment Now Includes Biologics

The type of JIA the child has and the extent of symptoms determine the treatment. The long-term treatment goal is preventing disease progression and joint destruction. The short-term goal is pain relief and reduced inflammation. Before the introduction of new treatment modalities, the only choice was to manage inflammation and pain with nonsteroidal anti-inflammatory drugs, such as naproxen and ibuprofen. Newer treatments that fall under the category of disease-modifying antirheumatic drugs help suppress inflammation and slow disease progression. In this category are biologics administered via injection (intravenous or subcutaneous) over several years. Recently, the FDA has approved several of these treatments: Humira (adalimumab), Orencia (abatacept), Enbrel (etanercept), Actemra (tocilizumab), and Ilaris (canakinumab).

Corticosteroids, such as prednisone, are also used because they quickly reduce inflammation, but because of their potential side effects, treatment consists of the smallest dose taken for the shortest time, often only until other medications begin to work. Other modalities used to treat JIA include physical therapy to maintain joint flexibility and range of motion, occupational therapy for help with daily life activities, and surgery in severe cases to replace a joint or improve its position.

Possible Complications

Complications from the disease and the medications used in treatment can sometimes occur in people with JIA. The most common complication of JIA is an inflammation of the middle layer of the eye, called uveitis. Uveitis can result in cataracts, glaucoma, and, potentially, blindness. The medications used in treatment can cause significant side effects, which should be discussed with the physician and pharmacist.

Prompt diagnosis and treatment significantly improve the prognosis of the child with JIA. Although JIA is not curable, under the watchful eyes of a multidisciplinary healthcare team and with proper medications, the outlook is very good. Talk to your pharmacist if you have questions about medications your child takes for JIA.

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