Erythrocyte Sedimentation Rate (ESR) Test is also known as the Sedimentation Rate (SER) Test, which is used to calculate the speed of the sedimentation of the red blood cell (erythrocytes or RBCs) within a span of an hour. In the test anticoagulated blood is used to see and measure the rate at which the plasma of the blood separates itself and the red blood cells settle in the bottom in a tube.


When in ESR Test Ordered

A doctor orders the patient to have the ESR test done when he suspects that some kind of disease or condition is causing the patient inflammation in the body. ESR test is used to detect quite a few inflammatory conditions.  It is difficult to detect the exact location of the inflammation so ESR test is done in conjecture with other tests. At times a doctor may ask the patient to repeat the ESR test several times over a particular span of time to monitor the course or the development of the inflammation caused by a condition or ailment.

Ailments Detected by ESR Test

Three main inflammatory diseases can be detected by ESR tests, Giant Cell arteritis, Rheumatoid arthritis, and Polymyalgia rheumatic. Apart from these other diseases that cause chronic or acute inflammation can be detected, like cancers, autoimmune diseases and other chronic or recurrent infections.

Understanding ESR Test Results

The sedimentation rate will vary with age, sex and at times even with labs. ESR is measured in millimeters per hour and a normal result doesn’t always mean that the person is not suffering from any inflammatory disease. On the other hand a not-normal result does not signify any specific ailment, the test result should be studied with the patient’s other medical results, conditions and history.

Greater than normal result – When the ESR Test indicates greater than normal value, it is caused due to inflammation which can happen due to autoimmune diseases like rheumatoid arthritis, few types of cancer, or infections. In this greater than normal result the red blood cells settle to the bottom of the tube faster than in normal cases.

Lower than normal result – There are cases where the ESR test result might be lower than normal, in such cases it can be due to the diseases such as sickle cell anemia, congestive heart failure and polycythemia, which is a condition where the person has higher number of red blood cells circulating.