The ESR test measures the erythrocyte sedimentation rate, which is how quickly red blood cells settle at the bottom of a blood sample. Doctors cannot use the results of the test to diagnose a specific disease because many different health conditions can cause the ESR to be high or low.

Doctors call the ESR test a nonspecific test, as it only confirms the presence or absence of inflammatory activity in the body. Doctors typically use other lab tests, clinical findings, and the person's health history alongside ESR test results to make a diagnosis.

inflamation usually occurs in the body as a result of underlying medical conditions, such as infection ,cancer, or an autoimmune disease

Doctors also use the ESR test to monitor how conditions, such as those below, are progressing or responding to treatment.

  •  rheumatoid arthritis, an autoimmune condition that causes inflammation in the joints
  • temporal arthritis, a type of blood vessel inflammation
  • polymyalgia rheumatica, a complication of temporal arteritis
  • systemic vasculitis, inflammation of the lining of the blood vessels

In this article, we look at the ESR test procedure and what the results might indicate. We also explain the possible risks of the procedure.

The result of the ESR test is the amount of plasma remaining at the top of the test tube after 1 hour.

The test is not specific to a particular condition, which means that doctors have to use the results alongside other clinical information to make an accurate diagnosis and determine whether or not the individual has a disease.

The normal refr for ESR results is 1–13 mm/hr for males and 1–20 mm/hr for females. These values can also vary depending on the person's age. People with ESR results outside the standard range may have a medical condition.

Low levels

People with low ESR values may have:

  • sickle cell anemia, a condition that affects the shape of red blood cells
  • leukemia, a blood cell cancer
  • a high red blood cell count
  • congestive heart failure
  • low levels of the protein fibrinogen in the blood
  • hyperviscosity, an increase in blood thickness
  • a very high white blood cell count

Moderately elevated results

A moderately elevated ESR may not always indicate a health condition.

However, it is possible that people whose ESR value is slightly high may have one of the following conditions:

  • rheumatoid arthritis
  • anemia, a reduced number of red blood cells
  • thyroid disease
  • kidney disease
  • red blood cell abnormalities, such as macrocytosis
  • some forms of cancer, such as lymphoma
  • tuberculosis, a type of lung infection
  • a bone infection
  • a heart infection
  • a systemic infection

Extremely elevated results

An extremely high ESR value, which is one above 100 mm\hr, may indicate one of these conditions:

  • multiple myeloma, a cancer of plasma cells
  • Waldenstrom's macroglobulinemia, a white blood cell cancer
  • temporal arteritis or polymyalgia rheumatica
  • hypersensitivity vasculitis, a reaction to an allergen that results in blood vessel inflammation

Doctors will typically compare the ESR test result with other test results to confirm a suspected diagnosis. They will also consider the symptoms and signs that a person is experiencing and their personal and family medical history.

People with abnormal ESR values may not always have a medical condition that requires treatment. Slightly higher levels can also occur due to pregnancy, menstruation, or advancing age.

People taking certain medications, such as oral contraceptives, cortisone, asprin, and vitamin A, may also have unusual test results.

If the doctor concludes that someone does have a medical condition, they are likely to prescribe a treatment specific to the condition. Treatment may involve:

  • antibiotics, where there is an infection
  • nonsteroidal anti-inflammatory drugs (NSAIDs), such as naproxen, diclofenac, and celecoxib
  • corticosteroid medications, such as methylprednisolone and dexamethasone.