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Erythrocyte sedimentation rate (ESR)

Hematology · also called Sed rate, Westergren ESR

What it measures

Measures how far red cells settle in a vertical tube in one hour. It is a non-specific marker of inflammation used to support diagnosis and monitor conditions like temporal arteritis and rheumatoid arthritis.

Specimen and preparation

Specimen: Whole blood in 3.2% citrate (4:1) or EDTA
Tube: Other top
Preparation: Test within 4 h at room temperature; keep the tube strictly vertical and away from vibration and sunlight.

Reference range

Group	Range
Male <50 y	0–15 mm/h
Male >50 y	0–20 mm/h
Female <50 y	0–20 mm/h
Female >50 y	0–30 mm/h
Child	0–10 mm/h

Reference ranges differ between laboratories, methods and populations. Always use the range printed on your own lab report.

Causes of high values

Infection (including tuberculosis)
Autoimmune and inflammatory disease
Multiple myeloma and other paraproteinemias
Anemia and pregnancy
Temporal arteritis, polymyalgia rheumatica
Malignancy

Causes of low values

Polycythemia
Sickle cell disease and spherocytosis
Hypofibrinogenemia
Extreme leukocytosis

Method

Westergren method (manual or automated)

Good to know

Rule of thumb for the upper limit: age/2 for men and (age+10)/2 for women. CRP responds faster and is less affected by anemia.

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