Erythrocyte Sedimentation Rate
Posted September 30, 2022 by Anusha ‐ 3 min read
The sedimentation rate or `sed rate`, for short is a blood test that checks for inflammation in your body. It’s one clue for your doctor that you might have a disease linked to inflammation, like arthritis or cancer, or an infection.
What is ESR?
The sed rate test measures how fast red blood cells fall to the bottom of a tube.
Inflammation creates proteins that make red blood cells fall more quickly.
Another name for this test is erythrocyte sedimentation rate (ESR).
Red blood cells are called erythrocytes.
Sedimentation is the process by which they fall to the bottom of the tube.
Why you might get ESR
Your doctor might order the sed rate test if you have symptoms like these:
Stiff, swollen, or painful joints
Pain in your shoulders, neck, or pelvis
Weight loss without trying
The sed rate test can be part of the process of discovering if you have one of these conditions:
Infection (including of the bones)
Arteritis (inflammation of the blood vessels)
Lupus (an autoimmune disease that damages the skin, joints, and other parts of your body)
Polymyalgia rheumatica (causes stiff and painful muscles)
Rheumatoid arthritis (autoimmune disease in which the immune system attacks your joints)
Systematic vasculitis (inflammation in your blood vessels)
Procedure of ESR
You don’t need to do anything special to prepare.
It’s just a basic blood test.
Let your doctor know what medicines (and supplements) you take before you have the test.
Certain drugs can affect the results.
Also let your doctor know if you are pregnant or are having your period.
A nurse or other health care provider will take a sample of your blood, usually from a vein in your arm.
They will first tie a band around the upper part of your arm to make your vein fill with blood and swell up.
Then they’ll clean the area with an antiseptic, and place a needle into your vein.
Your blood will collect into a vial or tube.
The process should only take a couple of minutes.
Afterward, you’ll get a piece of gauze and a bandage over the area to stop the bleeding.
You may feel a slight sting as your blood is drawn.
Afterward, you may have a small bruise.
You might feel dizzy and sore, and there might be some bleeding.
Normal ranges of ESR
The normal range is:
0 to 15 mm/hour in men younger than 50
0 to 20 mm/hour in men older than 50
0 to 20 mm/hour in women younger than 50
0 to 30 mm/hour for women older than 50
What does ESR test result means
Your sample will go to a lab. You should have the results in 1 or 2 hours.
A lab technician will place your red blood cells into a tall, thin tube and check how far they fall in 1 hour.
When you have inflammation in your body, abnormal proteins in your blood make red blood cells form into clumps.
These clumps are heavy, so they fall to the bottom of the tube more quickly than single blood cells.
The faster the blood cells sink, the more inflammation you have in your body.
The sed rate test reports in millimeters (mm) the distance between the clear liquid (plasma) at the top of the tube and your red blood cells after 1 hour.