How does the erythrocyte sedimentation rate indicate inflammation?

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blood analysis The physical and chemical properties of a sample of blood are examined during blood analysis. The examination of blood is important for the accurate diagnosis of disease.

The erythrocyte sedimentation rate (ESR) serves as a nonspecific indicator of inflammatory disease. It measures the speed at which red blood cells settle in a column of blood over the course of one hour.1

In the presence of inflammation, the body produces certain factors, such as fibrinogen, which act as coagulation proteins. These substances cause red blood cells to adhere to one another and clump together. Because these clumps are heavier and fall more rapidly out of the blood solution than individual cells would, an increased rate of sedimentation indicates the presence of these inflammatory factors.1

It is important to note that while the ESR is a useful marker for inflammation, it is not specific to any single condition and can also be elevated in cases of anemia.1