ESR – Westergren method

Check out this interesting history on ESR: Grzybowski_Ashort_IJLH2012

In general the greater amount of protein in the blood the faster it settles and therefore has a greater ESR. Usually results greater than 60 will be confirmed with a 60 minute ESR, but lower results can be safely reported in as little as 20 minutes and multiplied by a time factor.

High ESR can be caused by:

• Inflammation – for which this test is commonly used as a screening tool
• Infection
• Rheumatoid arthritis
• Rheumatic fever
• Vascular disease
• Inflammatory bowel disease
• Heart disease
• Kidney disease
• Certain cancers (multiple myeloma)
• Females
• Pregnancy
• Old age
• hyperfibrinigenemia
• macrocytosis

Low ESR can be caused by:

• Polycythemia
• Sickle cell anemia
• Leukocytosis
• microcytosis
• hypofibrinogenemia
• hypogamaglobinemia

There are two prevailing methods. The Wintrobe method uses 100mm thin tube whereas the Westergrenn uses a 200mm thicker tube. The modified-Westergrenn uses the same thicker tube but is usually automated and abbreviated to less than 60 minutes.

Lavender top tubes are most commonly used for this methodology and when loaded the automated instrument or method will diluted the sample with sodium citrate in a 1:4 ratio (5X factor). Black top tubes are also acceptable if validated with the testing system. They are sometimes made of glass so need to be handled with extra care. They contain a pre-aliquoted amount of sodium citrate so they must be filled to the correct level and not diluted a second time by the analyzer or protocol.

Sources:  https://medlineplus.gov/lab-tests/erythrocyte-sedimentation-rate-esr/  https://www.aafp.org/afp/1999/1001/p1443.html

Photo: https://www.fishersci.com/shop/products/polymedco-sediplast-autozero-esr-system-7/p-190433