How is granulocyte count measured?

To take a granulocyte count, scientists take a differential white blood cell, or WBC, count, according to the University of Nebraska Omaha. This count measures the presence of neutrophils, eosinophils and basophils, alongside other blood products.

In total, the granulocytes present in the differential WBC count should represent the following proportions of leukocytes:

• Neutrophil: 50 to 70 percent
• Eosinophil: 5 percent
• Basophil: 1 percent.

When granulocytes are outside these ranges, they give doctors reason to believe that there is an underlying pathology, MedlinePlus states. It is standard for the cells to be slightly outside their normal range. Doctors can then use the results to assume a diagnosis, but they may need to perform more tests.