2. OBJECTIVES
What is ESR?
Principle of ESR
Mechanism of ESR
Factors affecting ESR
Different methods of estimating ESR
Clinical significance of ESR
Errors
4. Introduction
Non specific test indicative of inflammation.
It is used an initial screening tool and also as a follow up test to
monitor therapy and progression or remission of disease.
Easy to perform.
Inexpensive.
Unit – measured in mm/hr.
5. What are the other acute phase reactants that you know of?
6. ESR is determined by the interaction between
factors that promote (fibrinogen) and factors that
resist (negative charge of RBC) sedimentation.
Normally, RBCs settle down slowly as they do not
form rouleaux. Instead, they gently repel each other
due to the negative charge on their surface.
Rouleaux are stacks of many RBCs that become
heavier and settle down faster.
Mechanism
7. Plasma proteins, especially fibrinogen, adhere to
the red cell membranes and neutralize the
surface negative charges, promoting cell
adherence and rouleaux formation.
ESR is directly proportional to the weight of the
cell aggregates.
It is inversely proportional to the surface area
Mechanism
8. Stages of Erythrocyte Sedimentation
Stage of rouleaux formation/aggregation 10 minutes
Stage of sedimentation/settling 40 minutes
Stage of packing 10 minutes
9. Factors That Increase ESR
Old age
Female
Pregnancy
Anemia
RBC abnormalities
Macrocytosis
Technical factors
Dilution problems
Increased temperature of
specimen
Tilted ESR tube
Elevated fibrinogen levels
Infection
Inflammation
malignancy
13. Reference method when undiluted blood is used.
Requirements:
Westergren pipette
Westergren stand
Anticoagulant diluent solution
Trisodium citrate (4:1)
EDTA
Westergren Method
14. Mix anticoagulated blood sample thoroughly. The
Westergren tube is filled with blood sample up to the “0”
mark. A rubber bulb or a mechanical device should be
used for filling. There should be no air bubbles in the
blood.
The tube is placed in a strictly vertical position in the ESR
stand and left undisturbed for 1 hr.
After exactly 1 hr, read the height of the column of
plasma above the red cell column in mm.
ESR is expressed in mm/hr.
Westergren Method
15. Male < 50 years: 0-15mm/hr
Male >50 years: 0-20mm/hr
Female <50 years: 0-20mm/hr
Female >50 years: 0-30mm/hr
Children: 0-10mm/hr
Reference Range By Westergren Method.
16. Advantages:
More reliable and gives accurate result.
Disadvantages:
More blood is required.
Difficult to fill blood in the tube.
PCV cannot be done.
Mouth pipetting can be hazardous.
17. Used to estimate both ESR and PCV
Requirement:
Wintrobe’s pipette
Wintrobe’s stand
Anticoagulated blood
EDTA
Double oxalate
Wintrobe’s Method
18. Mix the anticoagulated blood thoroughly.
Fill the wintrobe’s tube by using Pasteur pipette
upto the “0” mark.
Place the tube vertically in the stand.
Note the ESR at the end of 1hr.
Wintrobe’s Method
19. Males: 0-9mm/hr
Female: 0-20mm/hr
Children: 0-13mm/hr
Reference Range By Wintrobe’s Method.
20. EDTA blood is used instead of citrate.
2ml of EDTA blood is diluted with 0.5ml of 3.8% TSC or
0.85% NaCl.
Modified Westergren Method
21. Used in case of infants and if the blood is inadequate.
Requirement:
Fasting Capillary Blood (heel/finger tip/toe)
5.0gm/dl Tri Sodium Citrate solution
Landau Pipette (0-50mm)
Pipette stand
Suction device for drawing blood in the pipette
Capillaries for blood collection.
Micro Sedimentation Method
(Landau Method)
22. Attach landau pipette to suction device.
Draw 5.0gm/dl citrate upto the first line of the stem.
Draw blood upto the second line of the stem.
Draw the citrate+blood into the bulb and mix thoroughly.
Force back the mixture into the stem.
Set the upper level to the “0” mark at the top.
Place it vertically in the stand.
Note reading after 1 hour.
Micro Sedimentation Method
(Landau Method)
23. Male: 0-5mm/hr
Female: 0-8mm/hr
Newborn: 0-2mm/hr
Neonate to puberty: 3-13mm/hr
Reference Range by
Micro Sedimentation Method
(Landau Method)
25. Automated bench top analyser to measure ESR.
Blood collected in cuvets.
Sample is left to sediment.
18 degree slanting of the tubes causes
acceleration of the ESR.
Designed to measure 20 blood samples.
Results are comparable to Westergren method.
Results are available in approximately 25 minutes.
VES-MATIC 20
32. The filled Sedimat Westergren pipette is placed in the
SEDIMAT 15 automated ESR reader, which accelerates
the sedimentation under controlled conditions.
Based on the ability of blood to block the transmission
of infrared light
The reader displays the results of each sample on an
LCD display after 15 minutes.
The results are also stored in memory and can be
printed out.
SEDIMAT 15
33.
34. Zeta potential is a measure of the magnitude of the
electrostatic or charge repulsion/attraction between
particles
The Zeta potential results from negatively charged sialic
acid groups on the red cell membrane.
Fibrinogen and gammaglobulins decrease the Zeta
potential.
Decreased Zeta potential increases the rouleaux
formation.
This results in increasing ESR.
Thus explaining the mechanism behind raised ESR in
diseases.
Zeta Potential
35. It is the measurement of the ease with which RBCs will
pack under a standardised compaction – dispersion stress.
It is inversely proportional to the Zeta potential of these
cells when suspended in a particular plasma under
consideration.
Requires a Zetafuge.
Zeta Sedimentation Ratio
36. Zetafuge is a centrifuge which requires spin capillary
tubes in vertical position in four 45 seconds cycles.
Rouleaux formation and sedimentation in just 3 minutes.
Reading is called as ZETACRAT.
Zeta sedimentation ratio = (True Hct/Zetacrat) X100
Normal value is 51 – 54% for both sexes.
Zetafuge
37. A blood sample of 100ul contained in a vertical tube is
spun at 400rpm for 45 seconds.
The resultant force causes RBCs to travel outward until
they approach the outer edge of the tube.
The capillary tubes are rotated 180 degrees and
centrifuge is restarted.
As the centrifuge head regains its operating speed the
clumped RBCs now travel from the inner wall of the tube.
They are partially dispersed during the initial phases of
this journey before being deposited once more in the
outer wall.
Zeta Sedimentation Ratio
38. In the process they are exposed to the normal downward
gravitational forces and thus come to rest upon outer
edge of the tube at a point somewhat lower than the
starting point.
This process is repeated 4 times.
This causes the RBCs to travel in a zig-zag path in the
capillary tube and become more densely packed.
Four 45 seconds cycle of compaction, dispersion and
recompaction is employed.
At the conclusion of these 3 minutes, the degree of
compaction achieved by the RBCs is measured.
Zeta Sedimentation Ratio
39. To measure the ZSR, a capillary tube is read after the
compaction – dispersion cycles.
ZSR corresponds with the upper meniscus of the red cell
column.
The meniscus of the zetacrit is not completely horizontal.
The tail of the RBC rises above it on one side and a small
wedge of plasma depresses it on the other.
Zetacrit is marked at the knee of the curve between the
red cells and the meniscus.
Zeta Sedimentation Ratio
40.
41. Capillary tubes are easier and faster to fill.
Requires less sample.
Capillary tubes are cheaper than the regular ESR tubes.
ZSR is unaffected by the degree of anemia.
Advantages of ZSR
42. Results are expressed in % rather than in mm/hr.
Need to purchase specific capillary tubes and a Zetafuge.
Disadvantages of ZSR
43. All the situations where ESR is already used.
Anaemic patients.
Multiphasic health screening centers.
Blood bank donors.
Application of ZSR
46. Saves technician time.
Provides increased safety because the need for
sample manipulation is decreased.
Interface with the Laboratory Information System
(LIS).
Uses smaller volumes of sample.
Provides more rapid results.
Advantages of Automated Methods
47. Improper ratio of blood and anticoagulant.
Haemolysed blood sample.
Clotted blood.
Presence of air bubble.
Error due to sunlight, vibration, small bore size,
dirty and wet tube.
Delay in performing the test.
Sources of Error
49. Conditions Associated With
Very High ESR >100 mm/hr
1. Multiple myeloma
2. Connective tissue disorders - SLE, RA and
other autoimmune diseases
3. Tuberculosis
4. Malignancies
5. Severe anemia
50. Some Conditions With Low ESR
1. Polycythemia
2. Severe Leukocytosis
3. Sickle cell anemia
4. Hereditary spherocytosis
5. Congestive cardiac failure
6. Corticosteroid use
7. Hypofibrinogenemia
51. To eliminate the influence of anemia on ESR.
Corrected according to the volume of Red cells.
Corrected ESR
52. Find the horizontal line which represent the ESR at the
end of 1st hour.
Follow this across the chart till it intersects the vertical
line.
Vertical line represents the blood cell volume.
Follow the nearest curved line till it intersects the heavy
line at;
1. 42% per 100ml for females.
2. 47% per 100ml for males.
At the point of intersection read the value on the
horizontal line for the corrected ESR.
Correction of ESR
54. ESR is a non specific phenomenon and reflects
only change in plasma protein pattern and the
variation in RBC volume.
Cannot be used as a diagnostic tool.
Does not indicate the nature of the disease.
Limitations of ESR
55. To follow the course of the disease.
To establish the prognosis in certain chronic
diseases.
Increase in two or more consecutive tests
indicates continuation of the increased activity.
To distinguish between organic and non-organic
disorders.
To support the diagnosis.
Clinical Significance of ESR
56. 1. Henry’s Clinical Diagnosis And Management Of
Laboratory 22/E.
2. Dacie And Lewis Practical Hematology 10/E.
3. Textbook Of Medical Laboratory Technology –
Godkar 2/E.
4. Internet Sources.
References
Increase: dextran, methyldopa (Aldomet), oral contraceptives, penicillamine procainamide, theophylline, albumin and vitamin A.
Decrease: aspirin, cortisone, and quinine.
Formula to convert between diluted blood esr and undiluted blood esr:
Diluted blood esr = (undiluted blood esr x 0.86) – 12
Westergren pipette – 30cms length, 2.5mm diameter, 0-200 caliberation
Landau pipette 50cm in length….1mm inner bore…..0-50 markings
Pitfalls: correlation with the reference westergren method, prone to human error (mixing atleast 15 times followed by 5 mins limit before drawing blood into capillary tube).