Erythrocyte Sedimentation Rate (ESR)

Erythrocyte Sedimentation Rate (ESR)

Definition: The erythrocyte sedimentation rate (ESR) is a blood test that measures the rate at which red blood cells (erythrocytes) settle at the bottom of a test tube over a specified period, typically one hour. It is a non-specific marker of inflammation in the body.

Functions of ESR

Inflammation Indicator:

• ESR is primarily used to detect inflammation associated with various conditions, including infections, autoimmune diseases, and malignancies (blood cancer and solid organ tumor).

Disease Monitoring:

• It can help monitor the progression or response to treatment in inflammatory diseases such as rheumatoid arthritis and lupus.

Measurement of ESR

• Procedure:
• Blood is drawn from a patient and placed in a vertical tube. The distance that red blood cells fall in one hour is measured in millimeters. A higher rate indicates increased inflammation.
• Normal Values:
• Normal ESR values can vary based on age and sex but are generally lower in males (0-15 mm/hr) compared to females (0-20 mm/hr).

Clinical Relevance

Diagnosis of Conditions:

• Elevated ESR levels can indicate conditions such as infections, inflammatory diseases (e.g., rheumatoid arthritis, lupus), and certain cancers.

Monitoring Disease Activity:

• Changes in ESR can be used to assess disease activity and treatment response, particularly in chronic inflammatory conditions.

Limitations:

• ESR is a non-specific test; elevated levels do not indicate a specific disease. Other factors such as anemia, pregnancy, and age can also affect results.

Conclusion

The erythrocyte sedimentation rate is a valuable tool in clinical practice for detecting and monitoring inflammation. While it provides useful information about disease activity, it should be interpreted alongside other clinical findings and diagnostic tests.

References

1. Hartert H, et al. “Erythrocyte sedimentation rate: clinical significance.” Clinical Chemistry. 2000; 46(12): 1980-1985.
2. Hwang JY, et al. “The role of the erythrocyte sedimentation rate in the diagnosis of inflammatory diseases.” Korean Journal of Internal Medicine. 2018; 33(1): 12-24. DOI: 10.3904/kjim.2017.043
3. Horne BD, et al. “Erythrocyte Sedimentation Rate: A Review.” American Family Physician. 2004; 70(9): 1711-1717.