How is the ANC calculated?

The absolute neutrophil count (ANC) is a critical measure used to assess a patient’s immune status, particularly their risk for infections. It is calculated using the percentages of neutrophils, specifically the segmented forms (often referred to as "polys") and the band forms, as these are both types of neutrophils.

The formula involves taking the sum of the percentage of segmented neutrophils and the percentage of band neutrophils, which reflects the total proportion of neutrophils present in the blood. This sum is then multiplied by the total white blood cell (WBC) count and divided by 100 to convert the percentage into a count. This provides a more accurate representation of the body’s capacity to fight off infections.

Using only lymphocytes or monocytes would not accurately reflect the neutrophil component necessary for evaluating the patient’s risk for infection. Therefore, the calculation focusing specifically on the neutrophil components is essential for correctly determining the ANC.