Sedimentation

Sedimentation is the process of particles dissolved in a liquid settling or particles in a solution coming together and forming layers. Sedimentation rate may vary depending on the size, shape, and density of particles in a liquid.

In a medical context, sedimentation rate is often evaluated through a blood test called "erythrocyte sedimentation rate (ESR)" or "sedimentation rate (SR)". This test measures the rate at which red blood cells in the blood gradually settle over time in a tube left undisturbed for one hour. ESR can be used to detect inflammatory reactions or specific conditions in the body. Elevated sedimentation rate might indicate inflammatory conditions, infections, or other health issues.

What is Sedimentation Test?

The sedimentation test is a laboratory test that measures how quickly red blood cells in the blood settle within a certain period. This test is also known as erythrocyte sedimentation rate (ESR) or simply sedimentation rate (SR). A sample of blood is placed in a special tube and left for a specific duration, during which red blood cells slowly settle forming layers. During this process, the rate of settling is measured and usually reported as the amount of sedimentation within one hour in millimeters. Sedimentation rate can help indicate signs of inflammation, infection, or other health problems. However, this test alone is not sufficient for making a definitive diagnosis.

When is the Sedimentation Test Requested?

1. Inflammation and Infections:

Used to determine if there is an infection or inflammation in the body. For instance, bacterial or viral infections, inflammatory diseases like rheumatoid arthritis, or kidney infections may require a sedimentation test.

2. Autoimmune Diseases:

Used for the diagnosis or monitoring of certain autoimmune diseases. These include conditions like lupus, rheumatoid arthritis, Sjögren's syndrome, among others.

3. Cancer:

Sedimentation test might be requested for certain types of cancer, particularly lymphomas and cancers associated with lymph nodes.

4. Heart Diseases:

Can be helpful in some cases to identify or monitor heart diseases.

5. Monitoring Chronic Diseases:

Used to assess the course of chronic inflammatory conditions, kidney diseases, or liver diseases.

6. Chronic Pain Conditions:

Assisting in determining the cause of chronic pain or evaluating inflammation levels.

The sedimentation test serves as a general health indicator helpful in assessing various conditions. However, it's usually evaluated in conjunction with other clinical findings and test results. Therefore, it's quite common for a doctor to request a sedimentation test associated with specific conditions or symptoms.