Erythrocytes Sedimentation Rate (ESR)
The Erythrocytes Sedimentation Rate (ESR) test is a very simple and non-specific test, which has been in use for years. It helps in diagnosing conditions associated with inflammation.
During infections, diseases, and inflammation, some proteins (acute phase reactants) appear in the blood and cause the blood cells to clump together. This augments the process of sedimentation. Thus, in ESR, the sedimentation rate (the rate at which blood cells fall to the bottom of the tube) of erythrocytes is measured.
Why is the test ordered?
An ESR helps to detect inflammation due to fever, infections and autoimmune disorders. It is a nonspecific test as it does not reveal the location or cause of inflammation.
When is the test ordered?
A doctor may prescribe this test to monitor diseases like systemic lupus erythematosus, rheumatoid arthritis, and other inflammatory conditions. A physician may also advise this test if an individual experiences symptoms related to arthritis, joint pains, fever, muscular weakness, and fatigue.
How to prepare for the test?
Several types of medicines can affect the test results. Thus, it is important to inform the physician / diagnostic lab about all the medicines you are taking, before having the test done.
How is the sample collected?
A blood sample is collected from the vein in the arm of the individual using a needle.