what is esr in blood report

An Erythrocyte Sedimentation Rate (ESR) is a blood test that measures how quickly red blood cells settle to the bottom of a test tube. Normally, red blood cells sink slowly, but inflammation makes red blood cells stick together in clumps, which are heavier than single cells, so they sink faster. An ESR test can show if you have inflammation in your body, which is your immune systems response to injury or infection. An ESR test is not a stand-alone diagnostic tool, but it can help confirm a diagnosis of certain conditions, including inflammatory diseases such as rheumatoid arthritis, polymyalgia rheumatica, and giant cell arteritis. An increased ESR rate may occur in people with anemia, infection, cancer, and other medical conditions causing inflammation. The speed of your test result is a sign of how much inflammation you have, with faster ESR rates indicating higher levels of inflammation. However, an ESR test alone cannot diagnose what condition is causing the inflammation, and other tests are almost always needed.