What is the erythrocyte sedimentation rate?
The erythrocyte sedimentation rate (blood cell sedimentation rate) indicates how quickly the red blood cells in an unclottable blood sample sink. It is influenced by the number, shape and deformability of the red blood cells.
When is the erythrocyte sedimentation rate determined?
The erythrocyte sedimentation rate is used as a test to rule out inflammatory or malignant diseases. However, it is a non-specific value that does not provide an exact causal diagnosis. It can only provide a general indication of inflammation or malignant disease.
The doctor can also measure the BKS blood value for certain diseases as a control parameter in the further course of the disease. Nowadays, however, the C-reactive protein (CRP) is usually determined for this purpose.
What is a normal erythrocyte sedimentation rate?
Age and gender influence the reference range of the erythrocyte sedimentation rate. Normal values for women are below 20 millimeters (mm) after the first hour, for men below 15 mm. The normal ESR values for patients over 50 years of age are around 10 and 5 mm higher respectively.
As a rule, the blood sedimentation rate is only determined after the first hour. Sometimes the doctor also determines the 2-hour value, but this has no further significance.
When is the erythrocyte sedimentation rate low?
If the erythrocyte sedimentation rate is low, this may be due to the following reasons, for example:
- Polyglobulia (increased number of red blood cells)
- Diseases with altered erythrocyte shape, for example sickle cell disease
- dehydration
If the blood sample was stored too cold before the measurement, falsely low ESR values are found.
When is the erythrocyte sedimentation rate elevated?
The erythrocyte sedimentation rate is too high in the case of inflammation and cancer. The extent of the ESR increase can provide information about the underlying disease. A moderate increase of up to 50 mm within the first hour is found in the following cases:
- Anemia
- Increase in blood lipids (hypertriglyceridemia)
- Tumor diseases
- Taking hormonal contraceptives
- after menstruation
- during pregnancy
- after an operation
The ESR can also be elevated due to measurement errors such as taking too little blood in the sample tube or storing the sample at over 25 degrees Celsius.
A sharp increase in the blood sedimentation rate to 50 to 100 mm within the first hour can have the following causes:
- infections
- advanced tumor diseases with metastases
- leukemia
- Anemia due to cell decay (hemolytic anemia)
- Chronic liver disease
- Chronic kidney failure
- Tissue necrosis (tissue death)
- Rheumatoid arthritis
- Collagenoses (connective tissue diseases)
- Vasculitis (inflammation of the blood vessels)
What to do if the blood sedimentation rate changes?
If there are no symptoms other than the altered blood sedimentation rate or if the patient had an infection shortly beforehand, the doctor will check the ESR value again after a week. If the blood sedimentation rate has then shifted back towards the normal range, it is sufficient to wait and check it again.
However, if the blood sedimentation rate is still elevated or there are other symptoms, further tests are necessary (such as a complete blood count, LDH, transaminases, creatinine, urine status). If necessary, the doctor will also perform an ultrasound examination of the abdomen or a chest X-ray.
