Absolute Neutrophil Count

What is Absolute Neutrophil Count?

Absolute Neutrophil Count (ANC) is a type of blood test which is conducted for estimating the number of Neutrophils in blood.

Neutrophil is a type of WBC and its nature is granulocytic. There are total five types of WBCs which are as follows:

Neutrophils
Eossinophils
Basophils
Lymphocytes
Monocytes

1, 2, 3 are Granulocytes (Cytoplasm contains granules like structure)

4, 5 are Agranulocytes (Cytoplasm does not contains granules)

WBCs provide defence mechanism in our body; specifically Neutrophils are responsible for fighting against infectious agents.

Image 1: Normal and abnormal neutrophils

Absolute Neutrophil Count helps to analyse the chances of infection development in our body. Absolute Neutrophil Count and absolute Granulocyte Count are interrelated, so estimating the ANC is also helps to measure Granulocytes amount or AGC (absolute granulocytes count). Absolute Neutrophil Count can be measured by estimating the number of Neutrophils in a cubic millimetre of blood. The unit is used for the ANC is per cubic millimetre.

The ANC cannot be measured directly; it can derive from the Differential Leucocytes count (DLC). Initially doctors are diagnosing Complete Blood Count (CBC), which include all the cellular components of blood including WBC, for obtaining more specific estimation, doctors prescribed to conduct the differential count. In differential leukocytes count, lab report provides the detail result of each type of WBCs estimation.

Active Neutrophils which can able to fight against infections are come in two forms, segmented Neutrophils (complete mature Neutrophils) and bands (nearly mature Neutrophils). To estimating the ANC, both forms are countable. Segmented Neutrophils is also termed as Polys.

Calculation

ANC calculation can be done in two ways:

By using the value of WBC count: If doctors prescribed both WBC count as well as Absolute Neutrophil Count, then the formula is: multiply your white blood count (WBC) x total neutrophils (segmented neutrophils% + segmented bands%) x 10 = ANC.

For example: WBC = 2.0, segmented Neutrophils = 14.8% and Bands 5%, then according to this formula, ANC= [{2 X (14.8+5)} X 10] = 396.

Image 2: ANC (absolute neutrophil count)

Without using the WBC count: The formula used to obtain ANC from absolute numbers is Absolute segmented Neutrophils + Absolute bands multiplied by 1000.

For example: ANC (0.4 + 0.1) x 1000 = 500

Ranges

As infection frightening functionality of Neutrophils is very important to keep ourselves infection free, the safe range of Absolute Neutrophil Count is in between 1.5 to 8.0 (1,500 to 8,000/mm3). If individual having ANC within safe range, then they need not follow restricted lifestyle on the basis of Absolute Neutrophil Count.

In a normal healthy individual usually has 1,500/mm3 ANC. But person with lower ANC means Absolute Neutrophil Count is 500/mm3 (Neutropenia) become vulnerable to infectious agents.

Clinical Significance

Among different types of WBCs, specifically Neutrophils work against infectious agents, whereas others are involved in managing allergic response, killing of parasites and restoring worn out cells.

absolute neutrophil count low

The lower level of Neutrophil than the normal is medically termed as Neutropenia. Neutropenia makes people more susceptible to infection, as sufficient Neutrophils are unavailable to fight against infectious agents (particularly bacteria or fungi).

Image 3: In inflammation, neutrophil count is high

Neutropenia is often detected after giving chemotherapy, radio-active treatment or blood transfusion or bone marrow replacement. The fact about the reduction of Absolute Neutrophil Count is restoring the normal blood composition takes time, as slowly bone marrow is repairing and immature blood cells also required time to become matured or almost matured cells which will be countable in case of ANC.

ANC estimation is very important after treating cancer patient with chemotherapeutic agent, immune- suppressive treatment for organ transplantation and patient which has immunosuppressive diseases like HIV. The medical emergency situation also arises in case of Febrile Neutropenia. All these diseases are responsible for the frequent incidence of bacterial and fungal infection.

Prevention

For prevention it is advisable to follow personal hygiene, frequent proper hand washing habit generation, isolated from infected areas, and avoid communicating or interacting with an infected person, even if they had cold, wear masks to avoid dust and pollution.

References

https://depts.washington.edu/registry/Calculate.ANC.pdf
http://www.medicinenet.com/script/main/art.asp?articlekey=20030
http://www.cancer.org/treatment/understandingyourdiagnosis/examsandtestdescriptions/understanding-your-lab-test-results
http://www.marrowforums.org/tools/anc.html
http://www.mayoclinic.org/symptoms/neutropenia/basics/when-to-see-doctor/sym-20050854