This document summarizes the erythrocyte sedimentation rate (ESR) test. ESR measures the rate at which red blood cells settle in plasma over one hour and is used to detect inflammation. An abnormal ratio of plasma proteins causes red blood cells to stick together and form stacks that settle faster, increasing the ESR. Several factors can influence ESR rates, and values are interpreted based on sex and age. The Westergren method is commonly used to perform the test and involves mixing blood with an anticoagulant in a vertical tube and measuring settlement over one or two hours.

1. Hematology
Cihan University - Erbil
College of Health Technology
Department of Medical Biochemical Analysis
Erythrocyte Sedimentation Rate
(ESR)
Lab - 4
Dr. Raeid Duraid Thanoon
2nd year – 2nd Semester

2. A physician can use ESR to monitor a
person with an associated disease. It
is also used a monitoring tool for
response to treatment, the ESR
increase; when the disease improves,
the ESR decreases (tuberculosis,
autoimmune diseases…etc.).
Purpose

3. Blood containing anticoagulant agent
remains for a relatively long time in a
form of suspension, also in in vitro
conditions. The main factors making
RBC dispersed in plasma are negative
electrical charges (anti-sedimentation
factor) on their surfaces
Background

4. (negative charges on the red blood cell
surface due to the presence of the
carboxyl group of sialic acids in the cell
membrane). Opposite to these,
positive electrical charges of blood
plasma are directed. Thus, each RBC is
surrounded in this way by double layer
of electrical charges.
Background

5. The erythrocyte sedimentation rate is
the rate at which red blood cells
precipitate in a period of 1 hour. It's a
common hematology test which is a
non-specific measure of inflammation.
Background - Definition
ESR at zero time ESR after one hour

6. This measurement is important
because when abnormal ratio of
proteins (increase in plasma
fibrinogen, immunoglobulins) are
present in the blood, typically due to
inflammation or infection.
Background - Importance

7. The high proportion of these proteins
in the blood causes red blood cells to
stick to each other. The red cells form
stacks called "rouleaux" which settle
faster.
Background

8. Background
The Erythrocyte Sedimentation Rate
(ESR) is dependent on various factors,
e.g. on size and count of RBC, on
quantitative changes of the ratio
between the plasma proteins, on
concentration of lipids or pH of blood
plasma.

9.  Adult male: 0-15mm/hr.
 Adult female: 0-20mm/hr.
 Children: (<10) 0-10 mm/hr.
Normal values

10. Increased ESR
 Old age
 Female
 Pregnancy
 Anemia
 Macrocytosis
 Elevated protein: fibrinogen, gammaglobulins
 Drugs: methyldopa, Vitamin A
 Technical factors: dilution, high temperature,
vibration.
Factors affecting the ESR

11. Decreased ESR
 Extreme leukocytosis
 Polycythemia
 Hyperviscosity
 sickle-cell anemia
 Spherocytosis, microcytosis
 Low protein: fibrinogen, gammaglobulins
 Drugs: Aspirin, cortisone
 Technical factors: dilution, clotted sample
Factors affecting the ESR

12. No Effects
 Obesity
 Body temperature
 Recent meal
 NSAIDs (analgesic, antipyretic)
Factors affecting the ESR
nonsteroidal anti-inflammatory drugs

13. Methods
 Wintrobs' method
 Westergren method
 Modified Westergren method
 Automated method

14. Procedure
1. The skin surface is cleaned with
antiseptic, and an elastic band
(Tourniquet) is placed around the
upper arm to apply pressure and
cause the veins to swell with blood.
A needle is inserted into a vein and
blood is withdrawn.

15. 2. The blood sample must be mixed
with anticoagulant agent in this
test. Put 0.4 ml sodium citrate + 1.6
ml blood.
3. Mix gently without shaking then put
in the graded tube (Westergren
pipette) and leave it stand
vertically on the stand for 1 hour at
room temperature.
Procedure

16. 4. Read the amount of plasma that
appeared without moving it then
leave it to the second hour and read
another time.
Procedure

17. Sources of error:
1. Age of specimen - must be less than 2
hours at room temperature, less than 6
hours refrigerated.
2. Temperature - must be between 20-25° C
and blood must be at room temperature.
3. Incorrect ratio of blood to diluent.
4. Bubbles in the Westergren tube.
5. Vibration such as from a nearby
centrifuge will cause a false ESR.
Procedure Notes

18. THE END