ESR Test: Erythrocyte Sedimentation Rate Westergren

What is a Sedimentation Rate-Westergren ESR Test?

The erythrocyte sedimentation rate (ESR or sed rate) is the rate at which red blood cells sediment in a period of one hour. It is a common hematology test and is a non-specific measure of inflammation. To perform the test, anticoagulated blood is traditionally placed in an upright tube, known as a Westergren tube, and the rate at which the red blood cells fall is measured and reported in mm at the end of one hour.

The erythrocyte sedimentation rate (ESR or "sed rate") is a blood test that measures the rate at which red blood cells (erythrocytes) sediment (settle) in a tube of blood over a period of time. The test is often used to help diagnose and monitor inflammation in the body. The sedimentation rate is usually measured in millimeters per hour (mm/hr) and is often referred to as the "Westergren sed rate," after the person who developed the method for measuring it.

What Does High ESR Mean?

ESR can sometimes be useful in diagnosing diseases, such as multiple myeloma, temporal arteritis, polymyalgia rheumatica, various auto-immune diseases, systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, and chronic kidney diseases. In many of these cases, the ESR may exceed 100 mm/hour.

Elevated levels of ESR are usually found in people who have different types of diseases such as autoimmune disease, anemia, kidney disease, cancer, and other health complications.

In markedly increased ESR of over 100 mm/h, infection is the most common cause (33% of cases in an American study), followed by cancer (17%), renal disease (17%) and noninfectious inflammatory disorders (14%). Yet, in pneumonia, the ESR stays under 100.

What Does Low ESR Mean?

Similarly, low levels of ESR can also indicate certain diseases such as blood hyperviscosity, low plasma protein, leukemia and more.

Symptoms of Abnormal ESR levels

When the ESR levels in the bloodstream are outside normal ranges, the patient might experience certain symptoms such as the following ones:

• Abnormal weight loss
• Headaches
• Joint pain and stiffness
• Neck or shoulder pains
• Diarrhea and fever

Testing the ESR levels can give the patient an important “heads up” when it comes to his or her health.

What Medications Interfere with the Sedimentation Rate-Westergren ESR Test?

However, it is important to discontinue taking certain medications or drugs a couple of days before the test, to prevent them from interfering with the baseline ESR levels.

For example, the patient shouldn’t take:

• Androgens and estrogens
• Dextran
• Hypertension medication
• Oral contraceptives
• Aspirin
• Cortisone
• Antipsychotic drugs

The ESR test is usually done in combination with a CRP test to get more accurate results. Both these tests are included in a standard inflammation panel.