ESR by the Westergren method

Overview

The Erythrocyte Sedimentation Rate (ESR) by the Westergren method is a widely used hematology test that measures the rate at which red blood cells (RBCs) settle in a vertical, standardized tube of anticoagulated blood over the course of one hour. It is a non-specific indicator of inflammation and has long been used in clinical practice to assess the presence and progression of disease. The ESR is especially valuable as a prognostic marker, where a falling ESR indicates improvement and responsiveness to treatment, particularly in chronic conditions like tuberculosis. Although not diagnostic of a single disease, ESR is commonly performed during routine checkups, pre-operative assessments, and for monitoring inflammatory, autoimmune, and infectious disorders. The test is typically conducted with sodium citrate anticoagulant and measured using a Westergren tube, a transparent tube specifically designed for standardized measurement.

Symptoms

(Conditions where ESR testing is indicated or abnormal values may be observed)

1. Persistent fever or unexplained fatigue.
2. Joint pain and stiffness, often seen in rheumatoid arthritis and lupus erythematosus.
3. Swelling or chronic inflammation of tissues.
4. Weakness, pallor, and shortness of breath associated with anemia.
5. Recurring infections (bacterial, viral, or fungal).
6. Weight loss, night sweats, and prolonged illness suggestive of tuberculosis or cancer.
7. Swelling of legs, breathlessness, and fatigue linked with congestive heart failure (CCF).

Causes

(Clinical and pathological conditions associated with altered ESR values)

1. Increased ESR:
   1. Pregnancy.
   2. Anemia.
   3. Tuberculosis and other chronic infections.
   4. Autoimmune disorders such as rheumatoid arthritis, lupus, dermatomyositis, and nephrotic syndrome.
   5. Bacterial, viral, or fungal infections.
   6. Kidney diseases.
   7. Malignancies including lymphoma and multiple myeloma.
2. Reduced ESR:
   1. Polycythemia.
   2. Hyperviscosity syndrome.
   3. Sickle cell anemia.
   4. Leukemia.
   5. Chronic fatigue syndrome.
   6. Low plasma protein levels.
   7. Severe congestive heart failure.

Risk factors

(Groups more likely to show abnormal ESR values)

1. Children: ESR reference range is 0–15 mm/hr; higher values may indicate infection or inflammation.
2. Adults: Men typically have 0–15 mm/hr, women 0–20 mm/hr; risk of abnormalities increases with age.
3. Pregnant women: naturally elevated ESR due to physiological changes.
4. Patients with chronic autoimmune diseases, such as lupus or rheumatoid arthritis.
5. Individuals with long-standing infections, including tuberculosis and urinary tract infections.
6. Cancer patients, particularly those with multiple myeloma or lymphoma.
7. Cardiac patients, especially those suffering from congestive heart failure.
8. People with hematological conditions, including polycythemia, leukemia, and sickle cell anemia.

Prevention

(Approaches to ensure accurate ESR results and reduce disease risk factors)

1. Timely medical evaluation: ESR should be performed as part of routine and pre-operative checkups to identify hidden conditions.
2. Accurate sample collection:
   1. Use 3.8% sodium citrate solution in a light-blue capped tube.
   2. Collect 2 ml of blood and mix with 0.5 ml sodium citrate anticoagulant (ratio 1:5).
   3. Ensure testing begins within 2 hours of collection or store samples at 2–8 °C to prevent degradation.
3. Proper technique: The Westergren tube must be placed vertically and undisturbed for one hour for accurate readings.
4. Monitoring treatment response: Repeat ESR testing can help track recovery, especially in chronic diseases like tuberculosis, autoimmune disorders, and infections.
5. Preventing misleading results: Ensure patients are hydrated and not under immediate stress, as these can alter ESR.
6. Lifestyle modifications: Managing chronic conditions such as diabetes, hypertension, and infections may help reduce disease-related ESR elevation.
7. Clinical correlation: Always interpret ESR with patient history, physical examination, and other diagnostic tests since ESR is non-specific.