Rheumatoid Arthritis (RA)

What is Rheumatoid Arthritis (RA)? 

"Inflammatory arthritis" refers to a condition that causes joint pain, swelling, stiffness, and redness. Rheumatoid arthritis is a type of inflammatory arthritis that can affect the lining of joints throughout your body.

It usually begins in the small joints of the hands and feet, then symptoms can spread to wrists, knees, ankles, elbows, hips, and shoulders. Symptoms usually occur symmetrically, affecting the same joints on both sides of your body. Progression of RA can eventually lead to bone erosions and joint deformities. Inflammation associated with RA can also affect other parts of the body. Symptoms experienced in RA vary from person to person, can vary in severity, and can also come and go (flare vs relative remission).

The cause of rheumatoid arthritis is unknown. It can occur at any age, though it usually first appears between age 40 and 60. It affects approximately 1.3 million adults in the United States and is more common in women than in men.

Symptoms of RA

Signs and symptoms of RA include:

  • Joint swelling
  • Joint pain
  • Joint tenderness
  • Joint redness
  • Warmth of the joint
  • Stiffness of the joints, neck, or back upon awakening in the morning or after prolonged periods of rest or inactivity
  • Fatigue

Diagnosing RA

There is no one test that can diagnose RA, but blood and imaging tests can aid in the clinical diagnosis alongside a physical exam.

There are no specific blood tests to diagnose RA. The Rheumatoid Factor antibody is present in most people who have RA, but not all. It can also be found in people who do not have RA. ESR and CRP tests may indicate the presence of an inflammatory process in the body. Other tests such as ANA and anti-CCP may also be ordered by your rheumatologist.

X-rays can help track the progression of the disease over time.

The American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) criteria are often used as a guide for RA diagnosis. However, some patients who do not meet these criteria may receive a clinical diagnosis.

These criteria require that a patient have 6 points total from the domains below, using the highest score in each domain:

Number and site of involved joints

  • 2 to 10 large joints (from among shoulders, elbows, hips, knees, and ankles (1 point)
  • 1 to 3 small joints (from among MCP, PIP, second through fifth MTP, thumb IP, and wrists (2 points)
  • 4 to 10 small joints (3 points)
  • Greater than 10 joints, including at least one small joint (5 points)

Serological abnormality (RF or ACPA)

  • Low positive (above the upper limit of normal) (2 points)
  • High positive (greater than three times the upper limit of normal) (3 points)

Elevated acute phase response (ESR or CRP) above the upper limit of normal (1 point)

Symptom duration at least six weeks (1 point)