Absolute Lymphocyte Count Calculator

Lymphocytes are a vital part of the immune system – they are the largest group among the many kinds of white blood cells (WBC). Their name corresponds to the fact that they are the main solid compound of lymph. This word is derived from the name of the ancient Roman deity of fresh water, Lympha.

We recognize lymphocytes by their large nucleus. All of them cover the defensive function of the organism but have different roles and vary greatly. The whole group includes:

• NK – natural killer cells (which function in cell-mediated, cytotoxic innate immunity);
• T cells – for cell-mediated, cytotoxic adaptive immunity. Some of them, called CD4+, are attacked by the HIV virus, so their decrease can signal an AIDS infection; and
• B cells – for humoral, antibody-driven adaptive immunity.

💡 Another calculator you might be interested in is the absolute eosinophil count calculator.

The total lymphocyte count of a healthy person should range between 1.5 and 3 × 10³ cells/μL. This number elevates in states of viral infections and can very rarely be a sign of leukemia.

A low total lymphocyte count can be associated with increased infection rates after surgery or trauma. A progressive reduction of CD4+ T-cells (especially below 200 cells/μL) indicates immunodeficiency that can be linked to AIDS. According to the article Absolute lymphocyte count in the emergency department predicts a low CD4 count in admitted HIV-positive patients:

A CD4 count of < 200 cells/μL is very likely if the ALC (absolute lymphocyte count) is below 0.95 × 10³ cells/μL and less likely if the ALC is over 1.700 × 10³ cells/μL.

That means we can use the absolute lymphocyte count as a rough but easily obtainable marker of HIV-induced immunodeficiency.

To estimate the total lymphocyte count (ALC), you first need to do a complete blood count (CBC). The values of white blood cell (WBC) count and lymphocyte percentage (LYMPH%) are used in this equation for ALC:

ALC = WBC × LYMPH%

The calculated absolute lymphocyte count is expressed in thousands of cells per microlitre (10³ cells/μL).