Erythrocyte Sedimentation Rate
How fast red blood cells settle in a tube, an indirect, non-specific measure of inflammation.
| Typical reference range (male) | below 15 mm/h |
| Typical reference range (female) | below 20 mm/h |
Ranges vary by laboratory, method, age and sex: always use the range printed on your own report. Why labs differ.
What it measures
ESR measures how far red cells fall in a vertical tube in one hour. Inflammatory proteins such as fibrinogen and immunoglobulins make red cells stack together and settle faster.
Why it matters
ESR is used to detect and monitor inflammatory conditions such as giant cell arteritis, polymyalgia rheumatica and rheumatoid arthritis. It changes more slowly than CRP.
What a high result can mean
High values occur with infections, autoimmune and inflammatory diseases, cancers (especially multiple myeloma), anemia, kidney disease, pregnancy and older age.
What a low result can mean
Low values are usually not significant; very low values can occur with polycythemia, sickle cell disease and very high white counts.
What affects the result
ESR normally increases with age (approximate upper limit: age/2 for men, (age+10)/2 for women) and is higher in women and with anemia. Interpret with CRP.
Units and conversion
Usually reported in mm/h.
- From mm/hr: multiply by 1 to get mm/h
Also called on lab reports
ESR, Sed Rate, Sedimentation Rate, Sed Rate by Modified Westergren, Westergren ESR, Sed Rate, Westergren
Related tests: Inflammation & Immunity
This page is educational and does not replace advice from a healthcare professional.