ESR (Erythrocyte Sedimentation Rate) is a blood test that measures esr (erythrocyte sedimentation rate) levels in the blood. Normal range: ESR rises naturally with age and is a little higher in women. A common rule of thumb for the upper limit is age divided by 2 in men, and (age + 10) divided by 2 in women. It changes slowly, so it reflects sustained rather than sudden inflammation.. It is commonly used to a non-specific marker of inflammation used to detect and monitor inflammatory conditions..
What is ESR (Erythrocyte Sedimentation Rate)?
Measures how quickly red blood cells settle to the bottom of a test tube.
Why is it measured?
A non-specific marker of inflammation used to detect and monitor inflammatory conditions.
Normal Reference Range
ESR rises naturally with age and is a little higher in women. A common rule of thumb for the upper limit is age divided by 2 in men, and (age + 10) divided by 2 in women. It changes slowly, so it reflects sustained rather than sudden inflammation.
Note: Reference ranges may vary between laboratories. Always consult your healthcare provider for interpretation.
What Causes High ESR?
A high ESR is a non-specific signal of inflammation and has a long list of causes: infections, autoimmune and connective-tissue diseases (such as rheumatoid arthritis and lupus), and, importantly, polymyalgia rheumatica and giant cell arteritis, where a very high ESR supports the diagnosis. It also rises with anaemia, pregnancy, kidney disease, ageing and some cancers. Because it is so non-specific, a high ESR points to "something inflammatory" rather than to any one diagnosis.
What Causes Low ESR?
A low ESR is rarely significant. It can occur with polycythaemia (too many red cells), a very high white cell count, sickle cell disease, and some abnormalities of red cell shape that slow settling. It generally needs no action.
How Often Should ESR Be Tested?
ESR is ordered when an inflammatory, infective or autoimmune condition is suspected, and to monitor known conditions like polymyalgia rheumatica during treatment. It is frequently paired with CRP, which responds faster. Repeat testing tracks the trend rather than a single value.
Related Blood Markers
ESR is interpreted alongside CRP (a faster, more specific inflammation marker) and the full blood count, since anaemia and red cell changes affect the result. The pattern of both ESR and CRP guides how active an inflammatory process is.
Key Facts
- •Category: Blood Health
- •Unit of Measurement: mm/h
- •Test Code: ESR
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