Medical Analysis
Comprehensive Overview of Erythrocyte Sedimentation Rate (ESR) – Wintrobe Method
The Erythrocyte Sedimentation Rate (ESR), commonly referred to as the “sed rate,” is a fundamental haematology test that measures the rate at which red blood cells in anticoagulated whole blood descend in a standardized tube over a period of one hour. This test serves as a non-specific measure of systemic inflammation. The primary methods for measuring ESR include the Westergren method, the Wintrobe method, and automated ESR analyzers.
Prognostic Significance and Clinical Application
The ESR holds significant prognostic value. Most importantly, in any disease process, if repeated ESR values demonstrate a downward trend compared to previous results, it indicates that the patient is responding positively to treatment. Historically, before the availability of advanced modern diagnostic facilities, physicians would repeat the ESR test every 10 to 15 days to monitor treatment efficacy, particularly in conditions like Tuberculosis.
The Wintrobe tube itself is a 110 mm (11 cm) long tube with an internal bore diameter of 3 mm, closed at one end. Beyond ESR determination, other uses of the Wintrobe tube include the determination of packed cell volume, the preparation of a buffy coat smear to determine the LE cell phenomenon, the study of abnormal cells in cases of aleukemic leukemia, and performing differential counts in cases of markedly low WBC counts. After centrifugation, the Wintrobe tube reveals distinct layers: the plasma layer, the buffy coat (containing WBCs and platelets), and the packed RBCs (hematocrit).
Indications and Clinical Utility
ESR testing is indicated during routine checkups, pre-operative checkups, and for evaluating various conditions, including inflammatory processes, anaemia, infections, pregnancy, congestive heart failure, and autoimmune disorders such as Rheumatoid Arthritis, Lupus Erythematosus, Dermatomyositis, and Nephrotic Syndrome.
Technical Procedures and Standardization
Proper sample collection is paramount; 2-3 ml of blood should be collected in an EDTA (lavender-capped) tube. The sample should be transported immediately to the laboratory or stored at 2 to 8 temperature, with the procedure ideally starting within 2 hours of collection.
To prepare the ESR (Wintrobe) solution, 18 grams of K2EDTA are added to a volumetric flask containing 1 liter of distilled water and stirred until dissolved, followed by sterilization via autoclaving. Four drops of this solution are added to each tube and allowed to dry to form a powder. The test principle relies on RBCs settling due to gravity in anticoagulated blood, with Rouleaux formation increasing the rate of sedimentation, which is proportional to plasma proteins like fibrinogen and globulin. The final rate is measured in mm/hour. To perform the test, the Wintrobe tube is filled, mounted absolutely vertically in an ESR stand, and allowed to stand for one hour before recording the level at which RBCs have settled.
Normal Reference Ranges and Clinical Significance
| Age/Gender | ESR mm/hr |
| Male | < 10 |
| Female | < 15 |
The clinical significance of altered ESR levels is broad. Increased levels are associated with pregnancy, anaemia, tuberculosis, chronic infections (bacterial, fungal, viral), Rheumatoid Arthritis, Lupus, certain kidney diseases, and cancers such as lymphoma or multiple myeloma. Reduced levels may be seen in polycythemia, hyperviscosity syndrome, sickle cell anaemia, leukemia, chronic fatigue syndrome, low plasma protein, and congestive cardiac failure (CCF).
Prognostic Significance – ESR
| Condition | Prognostic Utility | Interpretation |
| Rheumatoid Arthritis (RA) | Reflects disease activity & therapy response | Upward ESR active disease, poor prognosis |
| Systemic Lupus Erythematosus (SLE) | Adjunct to CRP for flare assessment | Upward ESR suggests possible flare, upward disease activity |
| Temporal Arteritis (GCA) | Diagnostic & therapeutic monitoring | Downward ESR post-steroids suggests response; upward suggests relapse |
| Polymyalgia Rheumatica (PMR) | Tracks inflammatory control | Normalizing ESR suggests remission; persistent upward suggests active disease |
| Chronic Infections (TB, Osteomyelitis) | Indicates infection severity & chronicity | Persistent upward ESR suggests poor control, deep focus infection |
| Malignancies (Myeloma, Lymphoma) | Correlates with tumor burden | Very high ESR (>100 mm/hr) suggests poor prognosis |
For Non-Medicos: Understanding the ESR Test
The Erythrocyte Sedimentation Rate (ESR), or “sed rate,” is a simple blood test doctors use to check for hidden inflammation in the body. If you have an illness, your blood cells may clump together differently, causing them to fall to the bottom of a test tube faster than normal.
Why is this test done?
Think of the ESR as a “smoke detector” for your body. It does not tell the doctor exactly what is wrong, but it warns them that inflammation is happening somewhere. Doctors use it to help track conditions like infections, autoimmune diseases (where the body attacks itself), and certain cancers. It is also very helpful for seeing if a treatment is working; if your ESR goes down over time, it is usually a sign that you are getting better.
Important Things to Remember
Preparation: This test requires a specific blood sample (usually in a lavender-capped tube). It is best if the lab starts the test within two hours of drawing your blood.
Results: Your doctor will compare your result to a normal range based on your age and gender. However, because many things—like pregnancy or common anaemia—can change these numbers, an abnormal result does not always mean you have a serious illness.
The Big Picture: Never try to interpret an ESR result on your own. Always discuss it with your healthcare provider, who will look at the result alongside your symptoms and other blood tests to understand your overall health.
References:
Wintrobe, M. M. (1933). A macroscopic examination of the blood. American Journal of the Medical Sciences, 185(1), 58-71.
Westergren, A. (1921). Studies of the suspension stability of the blood. Acta Medica Scandinavica, 54(1), 247-282.
Brigden, M. L. (1999). Clinical utility of the erythrocyte sedimentation rate. American Family Physician, 60(5), 1443-1450.
Bedell, S. E., & Bush, B. T. (1985). Erythrocyte sedimentation rate: from folklore to facts. The American Journal of Medicine, 78(6), 1001-1009.
International Council for Standardization in Haematology (ICSH). (1993). Recommendations for measurement of erythrocyte sedimentation rate of human blood. American Journal of Clinical Pathology, 100(3), 339-343.
Jou, J. M., Lewis, S. M., Briggs, C., et al. (2011). ICSH review of the measurement of the erythrocyte sedimentation rate. International Journal of Laboratory Hematology, 33(2), 125-132.
Sox, H. C., & Liang, M. H. (1986). The erythrocyte sedimentation rate: guidelines for rational use. Annals of Internal Medicine, 104(4), 515-523.
Bottiger, L. E., & Svedberg, C. A. (1967). Normal erythrocyte sedimentation rate and age. British Medical Journal, 2(5544), 85-87.
Detwiler, D. A., & Tierno, P. M. (1990). The erythrocyte sedimentation rate. Laboratory Medicine, 21(9), 565-569.
Madan, N., & Sharma, U. (2012). Erythrocyte sedimentation rate: old and new perspectives. Journal of Hematology and Transfusion, 1(1), 1-5.
Bray, C., Bell, L. N., Liang, H., et al. (2016). Erythrocyte sedimentation rate and C-reactive protein measurements and their relevance in clinical practice. WMJ: Official Publication of the Wisconsin Medical Society, 115(6), 317-321.
Plebani, M. (2009). The erythrocyte sedimentation rate: still a useful test? Clinica Chimica Acta, 402(1-2), 213-214.
Al-Momen, A. K., & Al-Amri, A. (2000). The erythrocyte sedimentation rate: a revisit. Saudi Medical Journal, 21(1), 9-12.
O’Connell, J. B., & Kelleher, A. A. (2005). The ESR in clinical practice. The Journal of the Irish Medical Association, 98(3), 85-86.
FAQ’s:
What is the ESR test?
It measures how quickly red blood cells settle in an anticoagulated blood sample.Why is ESR performed?
It is a non-specific test used to detect inflammation throughout the human body.How is ESR measured?
It is measured by the Westergren method, Wintrobe method, or an automated analyzer.What tube is required?
A lavender-capped EDTA tube is required for collecting blood for this specific test.When to start testing?
The procedure should ideally begin within two hours of the initial blood collection.What is a Wintrobe tube?
A 110 mm long tube used for sedimentation rate and packed cell volume determination.How is blood prepared?
Blood is mixed with anticoagulant and placed in a vertical stand for one hour.What do results indicate?
Results help monitor disease activity and therapeutic response for various inflammatory conditions.What causes high ESR?
Infections, pregnancy, anemia, cancer, and chronic autoimmune disorders can increase the sedimentation rate.What causes low ESR?
Polycythemia, sickle cell anemia, leukemia, and congestive heart failure can decrease the sedimentation rate.
