Erythrocyte Sedimentation Rate (ESR)

Overview

The erythrocyte sedimentation rate (ESR) is a blood test that measures how quickly red blood cells settle at the bottom of a test tube containing a blood sample. It is a non-specific marker of inflammation, meaning it indicates the presence of inflammation but does not identify its cause or location^[1]. ESR is commonly used to monitor conditions such as infections, autoimmune diseases, and cancers. It is also influenced by factors like age, gender, and certain medical conditions^[2].

Scientific Background

ESR is influenced by the aggregation of red blood cells, which form clumps called rouleaux due to increased levels of proteins like fibrinogen during inflammation. These clumps settle faster, leading to a higher ESR^[1]. The test is based on Stokes" law, which states that the sedimentation velocity of particles increases with the square of their diameter. Thus, larger aggregates of red blood cells settle more quickly^[1].

Measurement and Testing

ESR is typically measured using a Westergren tube, where anticoagulated blood is allowed to settle for one hour. The distance the red blood cells have fallen is then measured and reported in millimeters per hour^[1]. Automated analyzers are also used for faster results. Factors affecting ESR include medications like aspirin and cortisone, as well as conditions like pregnancy and anemia^[2].

Reference Ranges

Normal ESR ranges are generally 0-20 mm/h for women and 0-12 mm/h for men^[3]. Values can vary based on age, gender, and other factors. For example, ESR tends to be higher in women, especially during pregnancy or menstruation^[1]. ESR does not change significantly with dialysis in patients with kidney disease^[1].

High Values

A high ESR indicates inflammation or infection and can be associated with conditions like rheumatoid arthritis, lupus, and certain cancers^[2]. It can also be elevated in non-inflammatory conditions such as anemia, kidney disease, and pregnancy^[1]. Symptoms may include fever, joint pain, or fatigue, depending on the underlying cause^[4].

Low Values

A low ESR is typically seen in conditions that increase blood viscosity, such as polycythemia or sickle cell anemia^[1]. It may also occur in cases of low plasma protein levels due to liver or kidney disease^[1]. Associated health risks depend on the underlying condition.

Improving Biomarker Levels

Improving ESR levels involves addressing the underlying cause of inflammation or other conditions affecting it. Lifestyle modifications such as maintaining a healthy diet, exercising regularly, and managing stress can help reduce inflammation^[4]. Medical interventions may include treating infections or autoimmune diseases with appropriate medications^[4].

Importance of Tracking

Monitoring ESR is important for diagnosing and managing inflammatory conditions. It helps healthcare providers assess the effectiveness of treatments and monitor disease progression^[4]. However, ESR should be interpreted alongside other diagnostic tests due to its non-specific nature^[2].

Disclaimer

The information provided in this document is for educational purposes only and does not constitute medical advice. It is essential to consult with a qualified healthcare professional for any health concerns or before making any decisions related to your health or treatment.