INTRODUCTION:

There are several methods to detect the presence of arthritis. In physical exam swollen joints or loss of motion, redness, erosion, joint distress is observed. X-rays are also done to check the internal damage of bones or joints. Blood tests are also conducted to detect the presence of arthritis. One such is the Erythrocyte Sedimentation Rate (ESR) Test.

ARTHRITIS:

It is joint inflammation. One or more joints can be affected. There are probably more than 100 different kinds of arthritis. Two forms of arthritis are the most common and are RA (Rheumatoid arthritis), OA (Osteoarthritis).

The disease is mostly seen in adults over 65 years of age, but can also be formed in younger adults, teenagers, and children. It is commonly seen in women rather than males and overweight people.

An autoimmune disorder that can cause pain in joints and inflammation in the body is the RA (Rheumatoid Arthritis). Uncontrolled RA is characterized by progressive synovial and cartilage damage and additional symptoms are associated with the bone. It is a chronic long-term disorder with swelling/inflammation and joint pain symptoms. During this time-period, signs and symptoms arise are called flares. Other cycles are considered remission periods. The ultimate aim of the RA treatment is for joint injury, pain relief and the normal function of the joint to avoid or at least reduce it. Since RA is a chronic disorder, the lifetime medication treatment is required like non-steroidal anti-inflammatory drugs (NSAIDS), disease-modifying anti-rheumatoid drugs (DMARDS) and Corticosteroid helps to decrease joint inflammation as well as pain, however, in addition to higher cost and many severe adverse effects, 30 percent of the patients have not responded to the treatment, unfortunately.^[1]

Cause of Rheumatoid Arthritis

ESR TEST:

The Erythrocyte sedimentation rate refers to a given time (generally 60 minutes) in millimeter (mm/hour) at which erythrocytes or sediment fall into a plasma tube of anticoagulated blood randomly drawn. Newer centrifugation methods will, however, achieve results in about 5 minutes.^[2][3] Dr. Edmund Faustyn Biernacki first discovered this phenomenon in 1897, when he noticed that there was a different blood settlement rate among individuals and the RBC (Red Blood Cells) is settled faster in the presence of higher fibrinogen levels.^[4] The anticoagulants that can be used for this test are Tri-Sodium Citrate or EDTA.^[5]

PRINCIPLE INVOLVED IN ESR TEST:

ESR is expressed in mm/Hg at the rate of RBC settles down in a narrow tube (Westergren) when blood anti-coagulation is allowed. At the end of an hour, it is determined by the column height of the transparent plasma.^[6]

There are three stages:

Stage of Aggregation: The pilling of the RBC’s occurred at the initial stage. The process is known as the formation of Rouleaux. It takes 10 to 15 minutes for the first time.

Stage of Sedimentation: It's the phase where sedimentation takes place in the actual decline of RBC's continuously. Out of 1 hr, it takes place in 30 to 40 minutes which depends on the tube length used.

Stage of Packing: It’s a final phase and also called a stationary phase. This results in a slower fall rate in which overcrowding causes the packing of sedimented RBCs on the column. The last 10 mins of 1 hour, it takes place.^[7]

Methods to determine ESR:

There are two primary ESR determination methods

Wintrobe method

Westergren method

Wintrobe Method:

The procedure is the same as the Westergren method except the Wintrobe tube is less than the Westergren tube in diameter with a length of just 100 mm. The anticoagulated EDTA mixed blood is drawn into the tube without the additional diluent, and after 1 hr the drop rate of RBC is calculated in millimeter. This approach is less precise since the overall potential abnormal value is lower with the shorter column than the Westergren approach. However, for practical demonstration purposes, it is used more frequently.

Wintrobe sedimentation rack ^[16]

Westergren Method:

This procedure needs to collect 2 ml of venous blood in a 0.5ml sodium citrate-containing tube. It must be held at room temperature not more than 2hrs or 4°C for about 6 hours. In a Westergren Katz tube, blood is drawn up to the mark of 200 mm. The tube is put on a rack at the room temperature for one hour (1h), in a strictly upright position, the distance from the lower end of the meniscus surface to the top end of the red cell sediment is estimated at that point. The ESR is the distance of erythrocytes dropping in 1 hr and measured in millimeter. ^[8]

Westergren Method^[17]

Wintrobe Tube:

At one end it's closed. It is about 110mm in length. The diameter of the internal bore is 2.5mm. On both sides, the tube is 0-10 and 10-0 calibrated.

Requirements:

Blood sample mixed with EDTA, Timer, Wintrobe tube, ESR needle, Wintrobe stand. The procedure should be completed within 2 hrs of the collection of blood.

Procedure:

Carefully blend the anti-coagulated blood. Using Pasteur pipette to fill the Wintrobe tube at mark 0. Place the tube in a stand vertically. At the end of 1 hour, observe the ESR.

Westergren Tube:

It is 30cm long. The diameter of the internal bore is 2.5 mm. Approximately 1ml of blood can hold in it. Opens at each end. It can be calibrated up to down; 0-200mm.

Requirements:

Trisodium citrated anticoagulated blood. Timer, Rubber bulb, Westergren tube, and stand.

Procedure:

Carefully blend the blood. Use a rubber bulb to draw blood into the tube to mark 0. Remove the blood from the lower end of the tube. Pour the blood in the tube and stand vertically in the Westergren stand. Observe the time and note down reading.^[9]

Normal ESR (mm/hr) = Age (in years) + 5 (if female)

Normal values for the ESR test (Erythrocyte Sedimentation Rate) are as given below:^[18][19]

Male >50 years old < 20 mm/hr

Male <50 years old < 15 mm/hr

Female <50 years old < 20 mm/hr

Female >50 years old < 30 mm/hr

Child < 10 mm/hr ^[20]

Scatter plot of the result of micro ESR and conventional approaches at 1hr.^[21]

X-axis: Time Y-axis: ESR value at mm/hr

Factors affecting ESR:

Physiological Factors:

Plasma Factors:

By decreasing the negative charge of RBC, fibrinogen, cholesterol, and globulin increase the ESR. The negative charge prevents the combined RBC. Plasma albumin decelerates RBC sediments.

Red Cell Factors:

Red cell mass increased – ESR reduced. Red cell mass is reduced- ESR is increased. Microcyte sediments slowly compared to Macrocyte as its sediments quickly than normocyte. ESR may also be affected by the erythrocyte structure. Even sedimentation of spherocytic cells is slowed.

Rouleaux formation:

As RBC aggregates to form a formation of rouleaux and settle down the area, this is considerably less than the amount of the corpuscle area. Therefore, the ESR increase is a significant factor.

Laboratory Factors:

Temperature:

The test must take place at 20-25°C. Increased temperatures lead to false outcomes because plasma viscosity is reduced. The refrigerated blood should be brought at RT. When the temperature increased 3°, the value of ESR increases by 1mm.

Time:

In 2 hrs of collecting a sample, the test must be completed. The EDTA sample must be held at 4°C and carried out within 6hrs.

Anticoagulant:

It is recommended to use EDTA or Tri-sodium citrate. Heparin modifies and should not be used to modify the cell membrane potential. ^[10]

Other Factors:

ESR can be improved by drugs, like dextran, theophylline, oral contraceptives, procainamides, methyldopa, penicillamines, and vitamin A, where it may be decreased by cortisone, quinine, and aspirin.

Clinical Significance:

ESR is a measure that is not specific. It is raised in a high range of inflammatory, infectious, malignant, and degenerative conditions, especially with increased levels of fibrinogens, immunoglobulins, and C-reactive proteins associated with variations in plasma proteins.^[11]

Increased ESR	Decreased ESR
Acute and Chronic infection	Hyperviscosity
Pregnancy	Decreased fibrinogen levels
Multiple Myeloma	Polycythemia
Systemic Lupus Erythematosus	Sickle Cell Anaemia
Anaemia	Spherocytosis
Rheumatic fever	Microcytosis
Macrocytosis
Rheumatoid arthritis
Inflammatory disease
Tuberculosis

Why ESR Test needs to be done?

ESR helps to determine a condition that is causing inflammation. These include vasculitis, inflammatory bowel disease, arthritis. ESR test is recommended if a person is experiencing anyone of the following conditions:

Loss of weight

Fever

Pain on the shoulder/neck

Joint Stiffness

Headache

Appetite loss

Anaemia

Advantages of ESR Test:

More reliable and gives accurate results

Inexpensive

Quick

Simple to perform

Disadvantages of ESR Test:

Not sensitive enough for screening

More blood is essential

PCV is not feasible

Hard to fill the tube with blood

Mouth pipetting can be hazardous ^[12][13]

Applications of ESR:

It is a marker of inflammation-autoimmune diseases like lupus or rheumatoid arthritis cause inflammation.

In certain inflammatory disorders, it is used to track the response to treatment.

Non-specific test

Not used for screening purposes (low sensitivity and specificity)

Inexpensive

This is done when a suspected disease is present, the ESR may have a sickness index of some value.^[14][15]

Summary:

It was seen that the performing rate of Erythrocyte Sediments can be a reliable and precise tool to measure ESR using a capillary tube as well as a blood sample. And it appeared to be a faster, cheaper, and more reliable method. Further, it is time-saving and accurate in diagnosis. This test doesn’t require veni-puncture, less equipment, less blood is required, and is economically more effective. All these features in various areas like screening, diagnostics, and disease monitoring become a more suitable and affordable alternative to the approach suggested by Westergren. Hence the results have an acceptable correlation with the Erythrocyte Sedimentation Test.

CONFLICT OF INTEREST:

No conflict of interest is declared by the authors.

REFERENCES:

1. https://en.wikipedia.org/wiki/Rheumatoid_arthritis

2. Batlivala SP. Focus on diagnosis: the erythrocyte sedimentation rate and the C-reactive protein test. Pediatr Rev. 2009;30(2):72-74.

3. Janson L, Tischler M. The Big Picture: Medical Biochemistry. New York, NY: McGrawHill; 2012.

4. Grzybowski A, Sak JJ. Who discovered the erythrocyte sedimentation rate? J Rheumatol. 2011;38(7):1521-1522; author reply 1523.

5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7045399/#:~:text=For%20ESR%20determination%2C%20blood%20anticoagulated,acid%20(EDTA)%20can%20used.

6. https://www.gundersenhealth.org/app/files/public/6563/Lab-Policies-Erythrocyte-Sedimentation-Rate-ESR---Sediplast---Affiliates-Lab-8763.pdf

7. https://laboratoryinfo.com/esr/

8. https://www.medicine.mcgill.ca/physio/vlab/bloodlab/ESR.htm#:~:text=There%20are%20two%20main%20methods,laboratories%20use%20the%20Westergren%20method.

9. https://www.slideshare.net/GovardhanJoshi/erythrocyte-sedimentation-rate

10. https://www.slideshare.net/GovardhanJoshi/erythrocyte-sedimentation-rate

11. https://laboratoryinfo.com/esr/

12. https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.slideshare.net%2Fhajramehdi7%2Ferythrocyte-sedimentation-rate-95243674&psig=AOvVaw18SHzmOI0qLAypcezhvFhj&ust=1600240575225000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCMDw7ezO6usCFQAAAAAdAAAAABAc

13. https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.researchgate.net%2Ffigure%2FComparison-of-the-ESR-C-reactive-Protein-and-Plasma-Viscosity-Tests_tbl3_12775052&psig=AOvVaw18SHzmOI0qLAypcezhvFhj&ust=1600240575225000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCMDw7ezO6usCFQAAAAAdAAAAABAn

14. https://www.google.com/url?sa=i&url=https%3A%2F%2Fslideplayer.com%2Fslide%2F5708102%2F&psig=AOvVaw3lN-0BDNDhDevlDBkdlqek&ust=1600322025792000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCIjB6qH-7OsCFQAAAAAdAAAAABAD

15. https://www.google.com/url?sa=i&url=https%3A%2F%2Fslideplayer.com%2Fslide%2F8437648%2F&psig=AOvVaw0F9DzMM43IapYHDOFPMWul&ust=1600322052862000&source=images&cd=vfe&ved=0CAIQjRxqFwoTCMCr0q7-7OsCFQAAAAAdAAAAABAD

16. https://www.medicine.mcgill.ca/physio/vlab/bloodlab/images/09imag/sedi-rack.jpg

17. https://images.slideplayer.com/20/6060343/slides/slide_17.jpg

18. Brigden ML, Clinical utility of the erythrocyte sedimentation rate. American family physician. 1999 Oct 1; [PubMed PMID: 10524488]

19. Böttiger LE, Svedberg CA, Normal erythrocyte sedimentation rate and age. British medical journal. 1967 Apr 8; [PubMed PMID: 6020854]

20. Al-Marri MR, Kirkpatrick MB, Erythrocyte sedimentation rate in childhood tuberculosis: Tuberculosis and Lung Disease. 2000 Mar; [PubMed PMID: 10751069]

21. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4614602/bin/emerg-3-50-g001.jpg

Received on 01.10.2020 Modified on 29.10.2020

Res. J. Pharmacology and Pharmacodynamics.2020; 12(4):177-180.

DOI: 10.5958/2321-5836.2020.00032.4