Practical Guide for ESR Test

Step-By-Step ESR Test Mannual

Muzzmal Ahtisham Tahir

Introduction

Erythrocyte sedimentation rate (ESR) is not entirely settled on sedimentation rate in view of gravity gauges that gauge the pace of red blood cells and erythrocytes precipitation in a given ESR tube. This test is for inflammation of tissues or for those impacted by a specific disease or illness.

Principle

The basic premise of the Erythrocyte sedimentation rate (ESR) test is the observation that, due to changes in blood composition and texture, red blood cells sink more quickly in cases of infection or inflammation. The Erythrocyte sedimentation rate (ESR) can be operated in a number of methods, such as:

1. Westergren method: This is the most popular method, which involves the use of a 2.4 mm internal diameter tube and a 1-hour sedimentation time.

2. Wintrobe method: This method performed in a 3.0 mm internal diameter tube and a sedimentation time of 1 hour.

3. Seditainer method: This method performed in a tube that has a sedimentation chamber and has a sedimentation time of 30 minutes.

4. Micro-ESR method: This method performed in a smaller tube and shorter sedimentation time which ranges from 20-30 minutes.

5. Automated ESR methods: These methods involve the use of the fully automated equipment like the Sysmex-ESR Auto-analyser or the Beckman Coulter ESR Analyzer.

6. Laser ESR method: This technique utilizes laser to estimate the rate of sedimentation of red blood cells.

7. Zeta Sedimentation Ratio (ZSR) method: This method involves determining the sedimentation rate of red blood cells in the zeta potential tube.

Still, each of the mentioned methods has its acceptance and drawback background, and the choice for any method depends on the laboratory’s preferences and the current clinical conditions.

 

Note: 

The Westergren method for Erythrocyte sedimentation rate (ESR) test is the most widely used and accepted method, and it is also considered as the gold standard method for ESR estimation.

 

1. Westergren method

2.   Alice Westergren developed the method for ESR measurement, which uses a 2.4 mm internal diameter tube and a 1-hour sedimentation time. This method, sensitive to changes in blood composition, is widely used in clinical diagnosis for inflammation, infection, and disease activity.

 

1.1. Materials Required

 

• Westergren ESR tubes (2.4 mm internal diameter, 100 mm long)
• Blood Specimen
• Anticoagulant (e.g., EDTA or Sodium Citrate)
• Sodium Citrate solution/ESR Reagent
• ESR Stand
• Stopwatch or timer 

1.2. Standard Operating Procedures (SOPs)

 

1. Collect blood specimen in an anticoagulant-coated tube.

2. Mix the blood gently but thoroughly.

3. Pour the blood into a Westergren ESR tube, leaving about 1 cm at the top.

4. Add ESR reagent to the tube, filling it to the top.

5. Mix gently and place the tube in a vertical positioned ESR Stand against gravity.

6. Start the timer or stopwatch.

7. Allow the tube to sit undisturbed for exactly 1 hour.

8. After 1 hour, read the distance (in millimeters) that the red blood cells have fallen from the top of the tube.

9. Record the result as the ESR value (mm/h).

 

1.3. Advantages

 

High sensitivity and specificity

Widely accepted and standardized method

Easy to perform and interpret

 

1.4. Limitations

 

Requires a specialized tube and equipment

Time-consuming (1-hour sedimentation time)

May be affected by factors such as temperature, humidity, and sample handling.

 

2. Wintrobe method

 

Maxwell Wintrobe introduced the Wintrobe method in 1935, a method similar to the Westergren method but with a 200mm tube length and 60 minute sedimentation time. This method, slightly larger than the Westergren tube, is widely used in clinical settings but may be more sensitive to blood composition changes. The Wintrobe method may be better for some clinical uses or patients with specific conditions, but the Westergren method is considered the gold standard for measuring ESR.

 

2.1. Materials Requird

 

• Westergren ESR tubes (2.4 mm internal diameter, 100 mm long)
• Blood Specimen
• Anticoagulant (e.g., EDTA or Sodium Citrate)
• ESR reagent available in market
• ESR Stand
• Stopwatch or timer  

2.2. Standard Operating Procedures (SOPs)

 

1. Collect a blood specimen in an anticoagulant-coated tube.

2. Mix the blood gently but thoroughly.

3. Pour the blood into a Wintrobe ESR tube, leaving about 1 cm at the top.

4. Add saline solution to the tube, filling it to the top making a ratio of 1:4.

5. Mix gently and place the tube in a vertical position.

6. Start the timer or stopwatch.

7. Allow the tube to sit undisturbed for exactly 60 minutes.

8. After 1 hour, read the distance (in millimeters) that the red blood cells have fallen from the top of the tube.

9. Record the result as the ESR value (mm/h).

 

2.3. Advantages

 

Similar to Westergren method, but with a slightly larger tube size

May be more sensitive to changes in blood composition

Easy to perform and interpret

 

2.4. Limitations

 

Requires a specialized tube and equipment

Time-consuming (1-hour sedimentation time)

May be affected by factors such as temperature, humidity, and sample handling.

 

 

3. Seditainer method

The Seditainer method is a modified version of the Westergren method, simplifying the ESR measurement process. It uses a specially designed tube with a built-in sedimentation chamber, reducing downtime and potential mistakes. With a 30-minute sedimentation time, it is more accurate than the Westergren method, though less sensitive to changes in blood composition.

 

 

3.1. Materials Required

 

• Seditainer ESR tubes (contains a built-in sedimentation chamber)
• Blood sample (venous or capillary)
• Anticoagulant (e.g., EDTA or citrate)
• Stopwatch or timer

 

3.2. Standard Operating Procedures (SOPs)

 

1. Collect a blood sample in an anticoagulant-coated tube.

2. Mix the blood gently but thoroughly.

3. Pour the blood into a Seditainer ESR tube, filling it to the indicated line.

4. Place the tube in a vertical position.

5. Start the timer or stopwatch.

6. Allow the tube to sit undisturbed for exactly 30 minutes.

7. After 30 minutes, read the distance (in millimeters) that the red blood cells have fallen from the top of the tube.

8. Record the result as the ESR value (mm/h).

 

3.3. Advantages

 

Simplified procedure

Faster sedimentation time (30 minutes)

Easy to perform and interpret

 

3.4. Limitations

 

Less sensitive than the Westergren method

Requires specialized tubes

May be affected by factors such as temperature, humidity, and sample handling.

 

 

4. Micro-ESR method

The Micro-ESR test is a modified version of the ESR test, utilizing a smaller tube and shorter sedimentation time. It is suitable for pediatric or geriatric patients with limited sample volume. Although less sensitive than the Westergren method, it provides reliable measurements and is often used in conjunction with other tests to diagnose and monitor inflammatory conditions. However, results may not be directly comparable.

4.1. Materials Required

 

• Micro-ESR test tubes (smaller than standard ESR tubes)
• Blood sample (venous or capillary)
• Anticoagulant (e.g., EDTA or citrate)
• Stopwatch or timer

 

4.2. Standard Operating Procedures (SOPs)

 

1. Collect a small blood sample (about 100-200 μL) in an anticoagulant-coated tube.

2. Mix the blood gently but thoroughly.

3. Pour the blood into a Micro-ESR test tube, filling it to the indicated line.

4. Place the tube in a vertical position.

5. Start the timer or stopwatch.

6. Allow the tube to sit undisturbed for exactly 20-30 minutes.

7. After the sedimentation time, read the distance (in millimeters) that the red blood cells have fallen from the top of the tube.

8. Record the result as the ESR value (mm/h).

  

4.3. Advantages

 

Requires smaller sample volume

Shorter sedimentation time (20-30 minutes)

Easy to perform and interpret

 

4.4. Limitations:

 

Less sensitive than the Westergren method

Requires specialized tubes

May be affected by factors such as temperature, humidity, and sample handling.

5. Automated ESR methods

Automated methods use specialized instruments to measure ESR, providing faster, more precise, and less variable results. These methods, such as the Sysmex ESR-Auto and Beckman Coulter ESR Analyzer, are widely used in clinical settings for rapid and accurate ESR measurements, reducing variability and environmental influences.

5.1. Materials Required

 

• Automated ESR instrument (e.g., Sysmex ESR-Auto, Beckman Coulter ESR Analyzer)
• Blood sample (venous or capillary)
• Anticoagulant (e.g., EDTA or Sodium citrate)

 

5.2. Standard Operating Procedures (SOPs)

 

1. Collect a blood sample in an anticoagulant-coated tube.

2. Load the sample into the automated ESR instrument according to the manufacturer's instructions.

3. Select the ESR test protocol and start the instrument.

4. The instrument will automatically measure the ESR value (mm/h) and display the result.

5.3. Advantages

 

Fast and efficient (results in minutes)

High precision and accuracy

Reduced variability

Easy to operate

 

5.4. Limitations

 

Requires specialized and expensive instrumentation

Maintenance and calibration are necessary

May be affected by instrument malfunction or technical issues

 

5.5. Some popular automated ESR instruments include

 

• Sysmex ESR-Auto
• Beckman Coulter ESR Analyzer
• Abbott ESR-Auto
• Siemens ESR-Automated

 

6. Laser ESR method

The Laser ESR method is an accurate reference method for measuring the sedimentation rate of red blood cells, offering high sensitivity and precision. This method is less affected by factors like temperature and humidity, making it a reliable and sensitive tool for ESR measurement in clinical settings.

6.1. Materials Required

 

• Laser ESR instrument (e.g., Laser ESR Analyzer)
• Blood sample (venous or capillary)
• Anticoagulant (e.g., EDTA or citrate)

 

6.2. Standard Operating Procedures (SOPs)

 

1. Collect a blood sample in an anticoagulant-coated tube.

2. Load the sample into the Laser ESR instrument according to the manufacturer's instructions.

3. Select the ESR test protocol and start the instrument.

4. The instrument will automatically measure the ESR value (mm/h) using laser technology.

5. The laser detects the sedimentation of red blood cells and measures the distance they travel in a given time.

6. The instrument calculates the ESR value based on the sedimentation distance and time.

 

6.3. Advantages

 

Highly sensitive and accurate

Fast and efficient (results in minutes)

Reduced variability

Easy to operate

 

6.4. Limitations

 

Requires specialized and expensive instrumentation

Maintenance and calibration are necessary

May be affected by instrument malfunction or technical issues 

 

7. Zeta sedimentation ratio (ZSR) method

The ZSR method, a variation of the standard ESR test, measures the sedimentation rate of red blood cells in a zeta potential tube, providing a sensitive and precise method for detecting and monitoring blood composition variations.

7.1 Materials Required

 

• Zeta potential tube
• Blood sample (venous or capillary)
• Anticoagulant (e.g., EDTA or citrate)

 

7.2. Standard Operating Procedures (SOPs)

 

1. Add a blood test in an anticoagulant-covered tube. 

2. Load the example into the zeta expected tube as indicated by the maker's guidelines. 

3. Place the cylinder in an upward position and begin the clock. 

4. Permit the cylinder to sit undisturbed for precisely 30 minutes. 

5. Following 30 minutes, read the distance (in millimeters) that the red platelets have tumbled from the highest point of the cylinder. 

6. Ascertain the ZSR esteem utilizing the accompanying equation: ZSR = (distance fallen/30 minutes) x 100. 

Note: The ZSR Method utilizes a zeta likely cylinder, which has a specific covering that upgrades the sedimentation of RBCs. The technique is exceptionally delicate and precise, and is utilized to distinguish unobtrusive changes in blood creation. The ZSR esteem is a proportion of the sedimentation distance to the time, and is communicated as a rate.

 

7.3. Advantages

 

Highly sensitive and accurate

Detects subtle changes in blood composition

Easy to perform and interpret

 

7.4. Limitations

 

Requires specialized tubes

May be affected by factors such as temperature, humidity, and sample handling

Requires careful calibration and maintenance of the zeta potential tube

Interpretation & Ref. Range

 

Normal range: 0-20 mm/h (varies depending on age, sex, and laboratory)

Increased ESR: indicates inflammation, infection, or disease activity

Decreased ESR: may indicate a lack of inflammation or the presence of certain medical conditions.

 

Factors Affecting ESR Test

 

• Age
• Sex
• Pregnancy
• Anemia
• Inflammation
• Infection
• Medications (e.g., aspirin, corticosteroids)

 

Precautions for ESR Test

 

Handle the blood sample and test tube gently to avoid hemolysis.

Ensure the test tube is free from contamination and air bubbles.

Use a consistent and accurate timer or stopwatch.

 

The general overview of ESR measurement, Standard Operating Procedures (SOPs) and interpretation is provided for professionals, highlighting the Westergren method as the gold standard. Each method has its advantages and disadvantages, and the choice depends on laboratory preferences and clinical requirements. Clinical correlation is crucial in ESR measurement.