Updated: September 29, 2019
Rheumatoid arthritis (RA) is an autoimmune disease in which the immune system of your body mistakenly attacks the joints. Left untreated, cartilage, the elastic tissue that covers the ends of bones in a joint, as well as the bones can get damaged.
Loss of cartilage can result in reducing the joint spacing between bones. Joints can become loose, unstable, painful and lose their mobility. Joint deformity also can occur which cannot be reversed. Therefore, early diagnosis and aggressive treatment to control RA is always advisable.
Rheumatoid arthritis most commonly affects the joints of the hands, feet, wrists, elbows, knees and ankles which is usually symmetrical. RA is also called a systemic disease as it can affect entire body systems, such as the cardiovascular or respiratory systems.
Based on the signs and symptoms Rheumatoid Arthritis can be diagnosed by a rheumatologist. RA may resemble other forms of inflammatory arthritis in its early stages. To make a proper diagnosis, the rheumatologist will ask questions about personal and family medical history, perform a physical exam and order diagnostic tests as no single test can confirm RA.
Personal and family medical history as well as recent and current symptoms such as pain, tenderness, stiffness and difficulty moving will be asked by your doctor.
In this examination each joint will be checked for tenderness, swelling, warmth and painful or limited movement. The number of joints and the way it gets affected will help in the diagnosis. For example, if the joints on both sides of the body are affected, it is an indication of RA. Other symptoms, such as rheumatoid nodules or a low-grade fever can also be detected by a physical examination.
The blood tests will measure inflammation levels and look for biomarkers such as antibodies linked with RA. High level of Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are indication of inflammation. Only a high level of ESR and CSP can not diagnose RA. But when combined with other test results, such as antibodies, helps make the RA diagnosis.
Rheumatoid factor (RF) is an antibody found in all most all of people affected with RA . But as RF can occur in other inflammatory diseases also, the presence of RF alone is not a sure sign of having RA. Anti-cyclic citrullinated peptide (anti-CCP) is another antibody which occurs primarily in patients with RA or exist even before symptoms start. A positive anti-CCP test is a strong indication of RA.
An X-ray, ultrasound or magnetic resonance imaging scan may be done to look for joint damage. Loss of bone within the joint known as erosions and narrowing of joint space can be detected by these test.
These test will not be helpful in diagnosing RA if the disease is in an early stage and has not started damaging the joints. This can be useful for advance stage of RA. X-rays are used to create detailed cross-sectional images of part of your body where as CT scans are X-ray procedures that combine multiple images with the help of a computer to generate cross-sectional views of the body. The test is more sensitive than standard X-rays in the detection of erosions.
MRI images are usually more detailed than those from CT scans as radio waves and strong magnets are used in MRI to create detailed pictures of the joints.