Erythrocyte Sedimentation Rate is a non-specific measure of what?

• A. Infection
• B. Coagulation
• C. Inflammation
• D. Anemia

Answer: (C)

ESR is a non-specific indicator of inflammation in the body. It measures how fast red blood cells settle in a tube over one hour. When inflammation occurs, acute-phase proteins like fibrinogen rise, causing red cells to stick together (rouleaux) and settle more quickly, so the ESR increases. Because many different inflammatory conditions can raise ESR, it signals that inflammation is present but doesn’t identify its cause.

It is not a test of coagulation, which involves clotting pathways (PT/INR, aPTT). While infection can cause inflammation and sometimes raise ESR, the test itself doesn’t specify infection. Anemia can affect ESR, but ESR is not used to diagnose anemia.