Aim: Determination of Erythrocyte Sedimentation Rate (ESR)
References:
1. Bull, B. S., & Brecher, G. (2005). Clinical Hematology: Principles, Procedures, Correlations. Lippincott Williams & Wilkins.
2. Lewis, S. M., Bain, B. J., & Bates, I. (2006). Dacie and Lewis Practical Haematology. Churchill Livingstone.
3. International Committee for Standardization in Haematology (ICSH) Guidelines for ESR measurement.
Objective:
To determine the erythrocyte sedimentation rate (ESR) in a given blood sample using the Westergren and Wintrobe methods.
Principle:
Erythrocyte Sedimentation Rate (ESR) is the rate at which red blood cells (erythrocytes) settle in a vertical tube of anticoagulated blood over a specific period. It is an indirect measure of inflammation and can be influenced by plasma protein concentration, especially fibrinogen and globulins.
Requirements:
Blood sample (anticoagulated with EDTA or sodium citrate), Westergren tube (200 mm long, 2.5 mm internal diameter), Wintrobe tube (100 mm long, 3 mm internal diameter), Westergren stand or Wintrobe stand, Pasteur pipette, Timer or stopwatch, Disposable gloves, 70% alcohol swabs
Methodology:
1. Westergren Method (Preferred Method)
1. Mix 4 parts of blood with 1 part of sodium citrate (3.8%) in a test tube.
2. Fill the Westergren tube up to the 0 mm mark with the blood sample.
3. Place the tube in the Westergren stand in an upright position at room temperature (18–25°C).
4. Start the stopwatch and allow the blood to stand undisturbed for 1 hour.
5. After 1 hour, record the level of clear plasma above the settled red cells in mm.
6. The ESR value is reported in mm/hr.
2. Wintrobe Method
1. Fill the Wintrobe tube up to the 0 mm mark with anticoagulated blood.
2. Place the tube in the Wintrobe stand in an upright position.
3. Start the timer and allow the blood to stand undisturbed for 1 hour.
4. Measure the distance from the 0 mm mark to the top of the settled red cells in mm.
5. The ESR value is reported in mm/hr.
Normal ESR Values
| Population | Westergren (mm/hr) | Wintrobe (mm/hr) |
| Men | 0-15 mm/hr | 0-9 mm/hr |
| Women | 0-20 mm/hr | 0-15 mm/hr |
| Children | 0-10 mm/hr | 0-7 mm/hr |
Sample result table:
| Sample ID | Method Used | ESR Value (mm/hr) | Population | Interpretation |
| 101 | Westergren | 12 | Male | Normal |
| 102 | Westergren | 25 | Female | Elevated |
| 103 | Wintrobe | 8 | Children | Normal |
| 104 | Westergren | 35 | Female | High |
| 105 | Wintrobe | 4 | Male | Low |
Precautions:
- Ensure the tubes are kept strictly vertical to avoid errors.
- Avoid air bubbles while filling the tubes.
- Perform the test at room temperature (18–25°C) to prevent inaccurate results.
- Read the results exactly at 60 minutes to maintain consistency.
- Use fresh anticoagulated blood samples for accuracy.
Clinical Significance:
Increased ESR: Suggests infections, inflammation, rheumatoid arthritis, tuberculosis, malignancy, anemia, and autoimmune diseases.
Decreased ESR: Observed in polycythemia, sickle cell disease, and conditions with abnormal red cell morphology.