What is a sed rate (erythrocyte sedimentation rate or ESR) test?
Sed rate (erythrocyte sedimentation rate, also known as ESR) is a simple blood test that helps detect inflammation in the body. The test measures the rate of fall (sedimentation) of red blood cells (erythrocytes) in a sample of blood placed in a tall vertical tube. Increased sed rate indicates inflammation.
Sed rate tests are also used to monitor the progress of an inflammatory disease.
A sed rate test is done through blood taken by needle from a vein in your arm.
Why is a sed rate (erythrocyte sedimentation rate or ESR) test done?
A sed rate test may be done when your doctor suspects you have a condition causing inflammation. Sed rate is called a nonspecific test because it does not diagnose specific illnesses but adds to the information about the presence and levels of inflammation.
A sed rate may be ordered to help in diagnosing and monitoring conditions including:
- Acute infection, such as tuberculosis and tissue necrosis (dead tissue)
- Chronic infection
- Rheumatoid or autoimmune disorder
- Acute inflammation
- Polymyalgia rheumatica and temporal arteritis