Laboratory Testing and Rheumatoid Arthritis

A chronic autoimmune disease, rheumatoid arthritis, or RA causes joint deterioration, along with stiffness and pain, inflammation, and loss of mobility. There are other symptoms associated with Rheumatoid Arthritis, including fever, fatigue, malaise, and the development of nodules under the skin. Additionally, those with RA can develop anemia, systemic complications. There may also be co-existing disorders and symptoms, for example, dry mouth and dry eyes that are often associated with Sjogren’s syndrome. Typically, RA affects the joints in a symmetrical manner. The most common joints affected are the hands and wrists, but the feet, neck, elbows, shoulders, and hips can also be affected by RA.

Rheumatoid arthritis usually develops between 40 and 60 years old. However, it can develop at any age. Women are the most affected by RA, with 70% of RA patients being women. The National Institutes of Health state that in the United States, there are over 1.3 million people who have the condition. If RA is not treated, it can work quickly and leave a person unable to work and can shorten their lifespan. The prognosis and course of RA vary from person to person. Some people find that it develops and progresses slowly, while others experience quick development and progression. RA can go into remission, and in a small percentage of RA patients, it can go away. For pregnant women with RA, they typically have a decrease of symptoms while pregnant, and the symptoms usually worsen after giving birth.

Rheumatoid Arthritis differs from the common form of arthritis, osteoarthritis. Osteoarthritis is often referred to as degenerative joint disease and is associated with aging and joint injury. Rheumatoid Arthritis is inflammation that affects the synovium or lining of the joints. Unlike osteoarthritis, it is usually symmetrical, for example, if one hip is affected, the other hip is too. It is thought that the disease can be inherited through genes, but there are probably other factors involved. It is thought viruses or bacteria can trigger the gene. Some scientists theorize changes in certain hormones can promote RA in those with certain genes that have had exposure to the agent that can trigger the disease.

Rheumatoid Arthritis Tests

To diagnose RA, a clinical evaluation must be conducted through a physical exam and a discussion of symptoms. Also, laboratory and non-laboratory tests are often performed to help diagnose the disease. These tests help distinguish it among the other forms of arthritis and other conditions that can cause similar symptoms. Testing can also evaluate the severity of RA, monitor the condition, determine the response to treatment, and monitor for any side effects treatments can cause.

RA Laboratory tests

Rheumatoid factor (RF) is used to help diagnose Rheumatoid Arthritis. In most people with RA, RF is present in significant concentrations. However, RF can also be present in those with other diseases and even in those who are healthy. When RF is positive in a person with RA symptoms, the test can be used to confirm the diagnosis of RA.

Cyclic citrullinated peptide (CCP) antibody can also be used to diagnose or confirm a diagnosis of RA. CCP is useful during the early stages of the disease, possibly even before the patient is symptomatic.  It can also be used in those who are RF-negative.

Antinuclear antibody (ANA) is used as a screen for specific autoimmune disorders, which may include RA. However, this test is most commonly used to diagnose systemic lupus erythematosus (SLE).

Erythrocyte sedimentation rate (ESR) determines activity related to the disease and if there is the presence of inflammation in the body. It can be used to help with the diagnosis of RA and to monitor and evaluate the condition. For those with RA, but not osteoarthritis, ESR will be increased.

C-reactive protein (CRP) is also used to determine the presence of inflammation and RA’s activity. It can be used to diagnose, monitor, and evaluate Rheumatoid Arthritis. CRP levels are elevated in those with Rheumatoid Arthritis, but not in osteoarthritis.

Complete blood count (CBC) is a group of tests that evaluates hemoglobin and red and white blood cells. It can monitor a decrease in white blood cells and anemia.

Comprehensive metabolic panel (CMP) is a group of tests that can be used to monitor and evaluate liver and kidney function.