Also known as: Erythrocyte Sedimentation Rate, ESR, Westergren Sedimentation Rate.

Erythrocyte sedimentation rate (ESR) is an easy, inexpensive, nonspecific test that has been used for many years to help diagnose conditions associated with acute and chronic inflammation, including infections, cancers, and autoimmune diseases. ESR is said to be nonspecific because increases do not tell the health provider exactly where the inflammation is or what is causing it, and also because it can be affected by conditions other than inflammation. Because it is nonspecific, ESR is typically used in conjunction with other tests. ESR aids in diagnosing two specific inflammatory diseases, polymyalgia rheumatica and temporal arteritism, a high ESR being one of the main test results used to support the diagnosis. The test is also used to monitor disease activity and response to therapy in both polymyalgia rheumatica and temporal arteritism.