Differential Lymphocyte Count

The Differential Lymphocyte Count test measures the relative proportion of lymphocytes in the blood. This test is a key indicator for a range of conditions and diseases that affect the immune system, including infections, allergies, autoimmune disorders, immune system disorders, etc. It is done as part of a complete blood count test that also measures other blood cell types.

Lymphocytes are a type of white blood cell (WBC) and form an important component of the immune system. These cells are responsible for recognizing and attacking foreign substances, such as disease-causing microorganisms (pathogens) as well as other infected or abnormal cells. They help protect the body against a wide range of illnesses. Therefore, abnormalities in the differential lymphocyte count indicate potential health conditions, including infections, allergies, autoimmune disorders, etc. 

A low lymphocyte count, also called lymphopenia, can indicate a weakened immune system characterized by several conditions, such as viral infections, immunodeficiency disorders, autoimmune diseases, etc. A compromised immune system may prompt an increased risk of infections and other illnesses. On the other hand, a high lymphocyte count, also called lymphocytosis, can indicate an overactive immune response which may potentiate the risk of autoimmune disorders, such as rheumatoid arthritis, multiple sclerosis, etc. Lymphocytosis is characterized by a variety of conditions, such as inflammations, allergies, or active infections. 

Usually, the Differential Lymphocyte Count test needs no special preparation; eat or drink as per your daily routine. Its test result ranges are approximate and may differ slightly between different labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. The results will help them determine your medical condition, make recommendations for lifestyle modifications such as diet and exercise, decide whether or not medication will be required to manage your condition, and formulate an overall treatment plan.