This lab test measures lymphocytes which are a critical component of the immune system. Lymphocytes are elevated with viral infections and certain conditions such as Crohn's disease.

Lymphocytes Overview

Reviewed: April 22, 2014

Lymphocytes are a specific type of white blood cells. They make up part of the immune system and help the body fight diseases or harmful substances.

Lymphocytes are measured as a percentage. The normal range for lymphocytes is 25-35%.


Blood draw


Fasting is not required before the test

What the results mean

Elevated lymphocytes may be seen with Crohn's disease, leukemia, ulcerative colitis, and viral disorders such as mumps, rubella, and hepatitis.

Lower than normal lymphocytes may be seen with congestive heart failure, renal failure, lupus, and AIDS.