Definition

Rheumatoid arthritis (RA) is a disorder of the joints. It causes pain, swelling, stiffness, and loss of function in the joints.

Rheumatoid Arthritis © Nucleus Medical Media, Inc.

Causes

RA is caused by a problem with the immune system. It begins to attack healthy tissue. It is not clear what makes this happen. It is most likely a combination of factors in a person's genes and environment. Some causes may be:

• Genes—people with RA often have a specific genetic defect
• Defects in the immune system—may stop the immune cells from recognizing the body’s own tissues
• Infection with specific viruses or bacteria—may start an abnormal immune response
• Chemical or hormonal imbalances in the body

Risk Factors

RA is more common in women. It often starts in people who are between 30 to 60 years of age.

Other things that may raise the risk are:

• Having other family members with RA
• Heavy or long-term smoking

Symptoms

Pain and swelling usually happens in smaller joints, such as the hands, wrists, and feet. It also affects joints on the same side of the body.

Other problems may be:

• Pain, stiffness, and swelling in the morning and after inactivity that lasts more than 30 minutes
• Red, warm joints
• Deformed, misshapen joints
• Lack of energy
• Weight loss
• Muscle aches
• Small lumps or nodules under the skin

Diagnosis

The doctor will ask about symptoms and past health. A physical exam will be done. There are many diseases that have symptoms that are similar to RA. Tests will be done to rule out other health problems.

Blood tests may be done to look for inflammation and blood proteins linked to RA. Pictures may be taken to look for tissue swelling and changes in bone. This can be done with:

• X-rays
• Ultrasound
• MRI scan

Samples may be taken of fluid and tissues to look for signs of RA. This can be done with:

• Arthrocentesis—fluid from the joint
• Synovial biopsy—a piece of the lining of the joint

Treatment

There is no cure for RA. The goal of treatment is to slow damage, ease pain, and improve movement. Steps may include:

Prevention

There are no guidelines to prevent RA.