A high sedimentation rate is indicative of inflammation somewhere within the body, according to WebMD. Patients who have high sedimentation rates may have certain autoimmune diseases, cancer, kidney disease, joint inflammation, or bacterial or viral infections.
A sedimentation rate is measured with a simple blood test, according to WebMD. After blood has been taken from the patient, a small sample can be placed in a test tube and left for one hour. After an hour, the concentration of red blood cells that have settled in the bottom of the test tube is measured. High concentration of red blood cells correlates with a high sedimentation rate.