July is Juvenile Arthritis Awareness Month.

Arthritis is a complex family of musculoskeletal disorders consisting of more than 100 different diseases or conditions that destroy joints, bones, muscles, cartilage, and other connective tissues, hampering or halting physical movement. Juvenile arthritis (JA) is a basket term used to describe the many autoimmune and inflammatory conditions that can develop in children ages 16 and younger. Arthritis typically affects joints — the word "arthritis" literally means joint inflammation — but JA can involve the eyes, skin, and gastrointestinal tract as well.

A 2007 Centers for Disease Control and Prevention (CDC) study estimates that 294,000 U.S. children under age 18 (or one in 250 children) have been diagnosed with arthritis or another rheumatologic condition. Juvenile arthritis affects children of all ages and ethnic backgrounds. The form of arthritis that children experience is not the same as grandpa's aches and pains but an autoimmune disorder where the body's immune system is attacking the joints. This condition is extremely serious and, if untreated, can result in death.

Types

There are several different types of juvenile arthritis. According to the CDC, three clinical classification schemes exist: juvenile rheumatoid arthritis (JRA), juvenile chronic arthritis (JCA), and juvenile idiopathic arthritis (JIA). The most common form of juvenile arthritis in the U.S. is JRA, which involves at least six weeks of persistent arthritis in a child younger than 16 years with no other type of childhood arthritis.

JRA can affect one joint or many and in some cases, it affects the entire body causing swollen lymph nodes, rashes, and fever. Commonly, the signs and symptoms of juvenile rheumatoid arthritis include:

  • Pain. Sometimes children do not complain of joint pain, yet they will limp — especially first thing in the morning or after a nap.
  • Swelling. Joint swelling is usually first noticed in larger joints like the knee.
  • Stiffness. Children with JRA often appear clumsier than usual, particularly in the morning or after naps.

JRA has three distinct subtypes: systemic (10 percent), polyarticular (40 percent), and pauciarticular (50 percent). For the latter two types, girls are much more commonly affected. For the systemic type, the peak age of onset is one to six years old, and about 50 percent of cases result in a very short stature in adulthood. In all types of JRA, about 40 to 45 percent of patients still have active disease after 10 years.

Most children with arthritis have times when the symptoms get better or go away (remission) and other times when they get worse (flare). In children, arthritis can cause growth problems or it can cause bones and joints to grow unevenly.

Origins

Researchers and doctors have great difficulty in describing the epidemiology of juvenile arthritis. No known cause has been pinpointed for most forms of JA, nor is there evidence to suggest that toxins, foods, or allergies cause children to develop the disease. Some research points toward a genetic predisposition, which means the combination of genes a child receives from family members may cause the onset of arthritis when triggered by other factors. As JA's prevalence rises — and the belief is that the number of cases of children with JA is increasing — researchers are working to develop a more sophisticated understanding.

It is known that JA is usually an autoimmune disorder, in that the immune system attacks some of the body's healthy cells and tissues. Scientists don't know why this happens but some think it's a two-step process in children: a child is genetically predisposed to get the condition and then something like a virus sets off the arthritis.

Diagnosis

The diagnostic process can be long and detailed and will involve a physical exam, lab tests, and x-rays, while examining symptoms and family history. There is no single blood test that confirms juvenile arthritis. In children, the key to diagnosis is a careful physical exam, along with taking a medical history. The diagnostic steps, such as laboratory work and x-rays and other imaging tests, are meant to rule out other potential causes of symptoms. Blood work, for example, can rule out the possibility of an underlying infection.

Treatment

Unfortunately, there is no cure for juvenile arthritis. The goal of treatment for JA is to relieve inflammation, control pain, and improve quality of life. Most treatment plans involve a combination of medication, physical activity, eye care, and healthy eating. Doctors prescribe treatments to reduce swelling, maintain joint movement, and relieve pain. They also try to prevent, identify, and treat problems that result from the arthritis. Most children with arthritis need a blend of treatments; some treatments include drugs, and others do not.

The medications that help relieve pain and inflammation include nonsteroidal anti-inflammatory drugs, or NSAIDs, corticosteroids, and analgesics. Those that alter the course of the disease, put it into remission, and prevent joint damage include a category of medication known as disease-modifying anti-rheumatic drugs (DMARDs) as well as a newer subset known as biologic response modifiers (biologics). Each child responds to treatment differently, and several different medications and/or dosages might be tried until a child responds positively. Some medications affect the immune system or have other side effects and so require frequent monitoring.

Source: The Arthritis Foundation.