Have a health question? Get reliable answers here.
Q: Could you please explain to me what sedimentation rate refers to and what the counts mean? I had recently my sedimentation rate measured and it was 68.
A: The erythocyte sedimentation rate (ESR) is a measure of the rate at which red blood cells settle. In order to determine ESR, the blood to be analyzed is first treated with a substance to prevent it from clotting (an anticoagulant), and then the measurement is carried out. The two methods most commonly employed for the determination of ESR are the Westergreen and the Wintrobe methods. In either of these methods, the red blood cells are allowed to settle for an hour in a properly calibrated tube, and the volume of plasma above the blood cell column is measured. In the Westergreen method, the tube is 200 mm in length. In the Wintrobe method, the tube is 100 mm in length. Also, in the Westergreen method, a sodium citrate diluent is added to the blood, while no such diluent is added to the anticoagulated blood in the Wintrobe method.
The ESR is often an indirect measure of inflammation. When there is an inflammation present, there is an increase in the blood of a protein referred to as fibrinogen, which makes the red blood cells settle quicker, thus increasing the measured value of ESR. However, in addition to fibrinogen, the ESR can be elevated in anemia (in which there is a decrease in the number of red blood cells) and the presence of other proteins in the blood. Thus, in addition to infection and anemia, an increase in the ESR may be found in cancer, leukemia, lymphoma, heart attack, diseases of the connective tissue (rheumatoid arthritis, lupus erythematosus, etc.), and inflammation of vessels (Wegener's granulomatosis, giant cell arteritis, polymyalgia rheumatica, etc.). In addition to being useful in diagnosis and treatment, the ESR may also be useful in following treatment and in the differentiation of diseases. For example, ESR is elevated in rheumatoid arthritis, while it is not elevated in osteoarthritis.
Typically, the ESR should be less than 20 mm/hr. Hence, in your case, in which ESR is 68, this is clearly elevated. Therefore, your doctor, without doubt, is carrying out careful diagbnostic studies to determine why it is elevated. As mentioned above, this can be due to numerous causes, some of which we have enumerated in the above discussion.
Updated: 09/12/99
Click Here to ask a MDAdvice.com doctor your medical question.
