Erythrocyte sedimentation rate (ESR).pptx

erytrocyte sedimentation rate

1. PRESENTED BY – DR. JASVEER KAUR MODERATOR – DR. SAHIL CHABBRA Erythrocyte sedimentation rate (ESR)

2. Erythrocyte sedimentation rate (ESR) The erythrocyte sedimentation rate (ESR) measures the rate of settling (sedimentation) of erythrocytes in anticoagulated whole blood . Anticoagulated blood is allowed to stand in a glass tube for 1 hour and the length of column of plasma above the red cells is measured in millimeters , which corresponds to ESR.

3. INTRODUCTION The usual tests for detecting an acute-phase response are estimation of CRP and measurement of the erythrocyte sedimentation rate (ESR) The ESR is slower to respond to changes in acute disease activity and is insensitive to small changes in disease activity. It is less specific than CRP because it is also influenced by immunoglobulins (which are not acute-phase reactants) and by anaemia. However, the conventional manual ESR method is simple, cheap and independent of a power supply, thus making it suitable for a screening test.

4. Stages of ESR There are three stages of erythrocyte sedimentation: • Stage 1: Formation of rouleaux or lag phase ( 10 minutes ): Red cells stack together like a pack of coins. The ESR depends mainly on this stage. • Stage 2: Sinking of rouleaux or decantation phase ( 40 minutes ): Rapid and constant sedimentation. The longer the tube, the longer is this stage and higher the value of ESR. • Stage 3: Packing of rouleaux (10 minutes): Slow sedimentation .

5. The ESR is affected by three factors: 1. Erythrocytes 2.Plasma Composition 3.Mechanical/Technical Factors

6. Erythrocytes Macrocytes tend to sediment rapidly than microcytes Alterations of ratio of red cells to plasma Decreased red cell mass in anaemia increases ESR Increased red cell mass in polycythemia decreases ESR Sickle cells and spherocytes are unable to form rouleaux and therefore ESR is low.

7. Plasma Composition In normal blood, the RBCs remain more or less separated. They are negatively charged and, therefore repel each other. ( Zeta Potential) Increased plasma protein concentration, most notable fibrinogen, immunoglobulins and acute phase proteins (C-reactive protein,ceruloplasmin ) cause a reduction in the negative charge of the RBCs and facilitates formation of rouleaux . Removal of fibrinogen by defibrination and increase in the albumin retard ESR

8. Mechanical/Technical factors It is important that the ESR tube be exactly perpendicular. A tilt of 30⁰can cause errors up to 30%. The rack, holding the tubes should not be subject to any movement or vibration. The sedimentation rate increases as the temperature increases. ESR tubes with a narrower than standard bore will generally yield lower sedimentation rates.

9. FACTORS AFFECTING ERYTHROCYTE SEDIMENTATION RATE Factors increasing ESR – Old age – Pregnancy – Anemia – Elevated fibrinogen – Macrocytosis – Technical factors: High temperature, tilting of ESR tube Factors decreasing ESR – Microcytosis – Low fibrinogen – Polycythemia – Marked leukocytosis – Technical factors: Vibration of tube during test

10. ERYTHROCYTE SEDIMENTATION RATE RANGES IN HEALTH Age Range (Years) ESR Mean (mm in 1 h) 10–19 8 20–29 10.8 30–39 10.4 40–49 13.6 50–59 14.2 60–69 16 70–79 16.5 80–91 15.8 Pregnancy Early gestation 48 (62 if anaemic ) Later gestation 70 (95 if anaemic )

11. Calculations Simple and commonly used formula for maximum upper limit of ESR are- Males- Age in yrs/ 2 Females- Age in yrs+10/2 Corrected ESR- To eliminate the influence of anemia on ESR Fabry’s fomula is used Corrected ESR= Measured ESR x 15/ (55-Hct)

12. SIGNIFICANCE OF ERYTHROCYTE SEDIMENTATION RATE ESR is elevated in a wide range of organic diseases. ESR is not a specific and diagnostic test for any disease. However, it is helpful in differentiating functional from organic disease. Raised ESR signifies presence of some organic diseases, which needs evaluation. ESR correlates with disease activity and therefore it is helpful in monitoring disease activity and response to therapy in acute rheumatic fever, bacterial endocarditis , tuberculosis , rheumatoid arthritis, temporal arteritis , polymyalgia rheumatica , and Hodgkin’s disease. ESR is an important criterion in establishing the diagnosis of temporal arteritis and polymyalgia rheumatica .

13. METHODS FOR ESTIMATION OF ERYTHROCYTE SEDIMENTATION RATE Westergren method Wintrobe method Automated analyzers Zeta sedimentation ratio Micro-ESR

14. Westergren Method The method for measuring the ESR recommended by the International Council for Standardisation in Haematology (ICSH) and also by various national authorities is based on that of Westergren method, which was developed in 1921 for studying patients with pulmonary tuberculosis. Requirements- Westergren pipette 30 cm in length,2.5 mm internal diameter. Marking on the tube is from 0 to 200 mm. It should be clean and dry Anticoagulant used- 3.8% trisodium - citrate dihydrate solution (1:4) Westergren rack. Timer.

15. Procedure Venous blood collected in trisodium citrate solution in 4:1 proportion Test is carried out within four hours of blood collection if specimen is kept at room temperature There should be no clots and air bubbles in the blood Blood is transferred into the pipette reaching 200 mm from the bottom of the tube. The pipette is kept upright in the ESR stand lying on the leveled surface The distance that the column of blood falls after 1 h is recorded and reported in mm after one hour.

16. WINTROBE METHOD

17. Automated ESR method VES- MATIC 20 instrument. ESR STAT PLUS SEDIMENT ROLLER 20LC

18. WORKING PRINCIPLE Blood is collected. Then sample is mixed by instrument Sample is allowed to stand at 18°slant from vertical Opto -electrical sensor measure ESR Data are elaborated and printed

19. WORKING PRINCIPLE Sample is placed in centrifuge Infrared laser tracks the erythrocytes plasma interface & takes multiple measurements Linear portion of sedimentation is identified Software algorithm to determine ESR result

20. Roller 20LC Roller 20 LC instrument can measure ESR of 18 samples in 10 minutes, which is a very short period compared to the Westergren method, which takes 60 minutes for ESR measurement.

21. Principles of Roller 20 LC The technology applied by Alifax's Roller 20 LC ESR instrumentation is Quantitative Capillary Photometry, which allows in just 20 seconds of analysis, to obtain the ESR result of the sample, expressed in mm/hour, as per guidelines and reference method. Quantitative Capillary Photometry studies the dynamic behavior of red blood cells (RBCs). The blood sample flows in a transparent capillary inside the instrument and the reactivity of the red blood cells is analyzed when this flow is suddenly interrupted: this abrupt interruption, together with the rheological characteristics of the sample itself, and the presence or absence of the proteins of the acute phase in it, starts or not the process of aggregation by stacking red blood cells. The diagnostic algorithm of the Alifax Roller 20 LC ESR instrumentation transforms the measurement performed in just 20 seconds of analysis, into a photometric quantity, expressed in mm/hour, without waiting for the entire stacking, sedimentation and sample stacking process.

22. Pediatric Test Tube With help of different kinds of adapters, the pediatric test tube can be inserted, for ESR in children.

23. Advantages of automated method Automated ESR analyzer is designed to accurately and precisely measure the sedimentation rate of erythrocytes in ESR tubes Less sample volume. Barcode Scanner Results in 20-30 minutes Built-in Printer No external influence of temperature, tilting of tubes. Higher number of samples can be processed simultaneously

24. Micro-ESR method

25. Requirements 7.5-cm heparin-free capillary tube, with an internal and an external diameter of 1.1mm and 1.5mm. 3.2% trisodium citrate Plasticine tray having modeling clay or sealing wax plates. Ruler

26. METHOD Blood is directly collected in micro-capillary tube, through heel prick or 3-4 drops of EDTA vial blood is mixed in a 4:1 ratio on a slide with a 3.2% trisodium citrate solution. The sample is then drawn into a capillary tube with a 30 to 45 degree angle. After 7 cm rising in the tube, a finger is placed over the top end of the capillary tube to prevent further rise. The tube is then repositioned perpendicularly and placed by slightly pressing into a plasticine tray having modeling clay or on sealing wax plates; in order to hold the tube in the desired vertical position or it can be sealed and stuck to wall. There after the distance from the highest point of the plasma column to the meniscus of the packed red cell column of each tube is measured with a ruler after one hour.

27. Micro-ESR

28. REFERENCES Dacie and Lewis Practical Hematology 10/E Henry’s Clinical Diagnosis And Management by Laboratory Methods 24/E Rodak’s Hematology Clinical Principles And Applications 6/E Essentials of Clinical Pathology Kawthalkar 2/E Internet sources.