$Unique_ID{BRK01480} $Pretitle{} $Title{What is a Blood Sed Rate?} $Subject{sed rate blood test special procedures laboratory tests erythrocyte sedimentation esr red cells cell settle sediment anticoagulated temporal arteritis polymyalgia procedure lab rates settling} $Volume{P-7, D-7} $Log{ Blood Sample After Separation*0002101.scf Blood Cell Count Usage in Diagnosis*0002102.scf} Copyright (c) 1991-92,1993 Tribune Media Services, Inc. What is a Blood Sed Rate? ------------------------------------------------------------------------------ QUESTION: Please explain--what is a blood sed rate, and what is normal? What determines the rate and how can it be changed? I am eager to know about this mysterious condition and will appreciate any enlightenment. ------------------------------------------------------------------------------ ANSWER: The sed rate, technically the erythrocyte sedimentation rate or ESR, measures the rate that red blood cells settle or sediment in an anticoagulated sample of venous blood. There is little sedimentation in normal blood because the red cells only have a slightly heavier density than the blood plasma. The sed rate varies with the age and sex of the patient. It is also affected by smoking, pregnancy, menstrual cycle, abnormal red cells shapes and other factors. In normal men, the red cells drift down at a rate of between 1-13 mm per hour. Women may show a rate of 1-20 mm/hour and still be considered normal. The test has been used to screen for numerous diseases, including infections and acute and chronic inflammations. It can also be used as a screening tool in patients with nonspecific problems or systemic disease. Repeated ESR testing may also allow doctors to monitor disease activity, helping them to track the progress of a disease and determining whether things are getting better or worse by noting significant increases or decreases in the sed rate. For example, in such diseases as temporal arteritis and polymyalgia, a normal ESR is very rare but repeated sed rate testing done over a period of time allows doctors to monitor disease progression. It is important to realize that the ESR is merely a test, useful for evaluating and following various conditions, but is not a disease in and of itself. Although once an important study of great assistance in helping to make a diagnosis for many patients, it is less so these days because of the development of so many new and more sensitive tests. Still in some cases it remains a very valuable tool. ---------------- The material contained here is "FOR INFORMATION ONLY" and should not replace the counsel and advice of your personal physician. Promptly consulting your doctor is the best path to a quick and successful resolution of any medical problem.