What is an ESR Test?
An ESR (erythrocyte sedimentation rate) test is a blood test that measures how quickly red blood cells (erythrocytes) settle at the bottom of a tube in one hour. It’s also known as a sed rate test or sedimentation rate test. The test is used to detect inflammation in the body, which could be caused by a variety of medical conditions such as infections, autoimmune diseases, and certain cancers.
How is the Test Performed?
To perform the ESR test, a healthcare provider will take a blood sample from the patient’s arm. They will clean the area with an antiseptic solution, and then insert a needle into the vein to draw blood. The blood is collected in a tube and sent to a laboratory for analysis.
The laboratory technician will place the blood sample in a tall, thin tube and add a special chemical that prevents the blood from clotting. The tube is then placed upright and left to sit undisturbed for one hour. During this time, the red blood cells in the tube will gradually settle at the bottom, leaving a clear liquid at the top. The distance that the red blood cells have fallen is measured in millimeters and is used to calculate the patient’s ESR value.
Interpreting the Results
The ESR test is a non-specific test, meaning that it can’t diagnose a specific medical condition. Rather, it’s used as a screening tool to detect inflammation in the body. A normal ESR range is typically between 0-20 mm/hr for men and 0-30 mm/hr for women. However, the normal range can vary slightly depending on the laboratory that performs the test.
If a patient’s ESR level is higher than the normal range, it could be a sign of inflammation caused by a variety of conditions such as infections, autoimmune diseases, and certain cancers. However, an elevated ESR level doesn’t necessarily mean that the patient has a medical condition that requires treatment. Other tests, such as blood tests or imaging tests, may be needed to diagnose the underlying cause of the inflammation.
Conclusion
An ESR test is a simple blood test that measures the rate at which red blood cells settle in a tube in one hour. The test is a useful screening tool for detecting inflammation in the body, but it can’t diagnose a specific medical condition. If a patient’s ESR level is higher than the normal range, further testing may be needed to diagnose the underlying cause of the inflammation.
