About ESR
ESR (Erythrocyte Sedimentation Rate) measures how quickly red blood cells settle to the bottom of a test tube over one hour — when inflammation increases blood proteins like fibrinogen, cells clump together and sink faster. It is a non-specific marker of systemic inflammation useful for detecting and monitoring autoimmune diseases, infections, and certain cancers, but it doesn't identify where the inflammation is coming from. ESR is typically interpreted alongside CRP and a full blood count to build a more complete clinical picture.