ESR or Erythrocyte sedimentation rate is a simple blood test performed in pathology laboratory since many years to detect inflammation or any type of infection in the body. It is frequently used test as it is cost effective for all patients. The test is non specific because it does not pin point exactly in which part of the body inflammation is present or the underlying cause of inflammation. Therefore physician recommend this test in conjunction with several other tests to confirm or rule out his diagnosis.
ESR test is frequently ordered by the doctor in autoimmune diseases, rheumatoid arthritis, systemic lupus erythematosus, cancer, tuberculosis, chronic fever, and several other infections in the body.However, ESR does not indicate any of this specific disease but only gives a hint to the doctor if he is suspecting any inflammation in the body.
Often ESR estimation is used to track the course of disease and response to the medicines which are recommended by the doctor. For example in tuberculosis of lungs, blood ESR is regularly monitored to observe the response of the drug. During the six to nine months of anti tuberculosis treatment, ESR gradually returns to its normal value. It suggests that the infection is in control and the condition is treated.
What Does Low Or High ESR Levels In Blood Mean?
Blood ESR is estimated in mm/hr or millimeter per hour. It is the calibration of clear fluid on top of the blood which is settled down at the bottom of the tube after one hour of time. Abnormal proteins in the blood cause the red blood cells to clump together and settle at the bottom. In adults the normal range of ESR is between 15 to 20 mm/hr. In children the range of normal ESR is considered to be between 3 to13 mm/hr. Women have slightly high ESR value.
Moderately high ESR may suggest an inflammation but there are several other causes which may also have slightly high ESR than normal such as in anemia, pregnancy, and menstruation and even after aging. However ESR value as high as 80 to100 and above has certainly been considered pathological and it indicates inflammation with certainty. This may indicate diseases such as rheumatic arthritis, rheumatic fever, temporal arthritis, multiple myeloma, tuberculosis, cancer, and several other inflammatory diseases and infections.
ESR is monitored repeatedly if it is high, firstly to know whether the inflammation process is increasing or to know the therapeutic response of medicines prescribed by the physician. In women there is temporary elevation of ESR during pregnancy and menses.
The erythrocyte sedimentation rate frequently remains high after the subsidence of all clinical symptoms of the disease. This means the disease process is still active at the subclinical level, for example as in case of rheumatic disease.
Low ESR is observed in certain conditions where the normal sedimentation rate of blood is suppressed. It is seen in conditions such as:
- Polycythemia vera where the red blood cell count is extremely higher than its normal value.
- Congestive cardiac failure.
- Sickle cell anemia (abnormality in red blood cells).
- Cancer of kidney.
- Leukocytosis where the white blood cell count is higher than normal.
Certain drugs may also affect the value of ESR. Erythrocyte sedimentation rate may be higher if the patient is taking following drugs:
- Oral contraceptive
- Vitamin A
- Procaine penicillin
Certain drugs can lower ESR such as cortisone, aspirin, and quinine.
If you are taking any drugs you should inform your physician so that it becomes easy for him to interpret ESR report.