What is a sedimentation rate?
A sedimentation rate is common blood test that is used to detect and monitor inflammation in the body. The sedimentation rate is also called the erythrocyte sedimentation rate because it is a measure of the red blood cells (erythrocytes) sedimenting in a tube over a given period of time. Sedimentation rate is often abbreviated as "sed rate" or ESR. Although this test measures a general state of inflammation, it is not specific to what causes the inflammation. It is elevated in inflammatory diseases, including arthritis as well as in autoimmune diseases such as lupus. It can also be elevated due to other conditions such as certain cancers and Grave's disease.