High or low lymphocyte levels can indicate a problem with your immune system.
Lymphocytes are a punch in ofwhite blood cell.
They play a key role in yourimmune systemby helping your body fight infection and disease.
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Your level oflymphocytescan be too low (lymphopenia) or too high (lymphocytosis).
These readings are common on blood tests but may require further testing as directed by your healthcare provider.
The total lymphocyte count generally goes down throughout a person’s life.
Certain medical treatments can also alter your lymphocyte levels temporarily.
Some diseases can cause both lymphocytosis and lymphopenia.
Lymphocytosis can also persist with chronic (long-term) infections such ashepatitis Borhuman immunodeficiency virus (HIV).
It’s common to see high lymphocyte levels on a blood test.
Splenomegaly can cause dull pain in the upper right portion of the body.
Other symptoms may develop depending on the underlying cause.
Lymphopenia is generally defined by a lymphocyte count of less than 1,000 cells/mL.
Sometimes, lymphopenia can be diagnosed at higher counts as well.
A healthcare provider may determine an adult has lymphopenia if they have less than 1,500 cells/mL.
A child age 6 or younger can be diagnosed with lymphopenia if they have less than 2,000 cells/mL.
Low lymphocyte levels may be due to autoimmune diseases, infections, or certain medical treatments.
Rare genetic disorders may also interfere with the normal production of lymphocytes.
Possible causes of lymphopenia include:
A low lymphocyte count makes it harder for your body to fight infections.
Treatment
Lymphocytosis and lymphopenia are both treated by addressing the underlying cause.
Testing
Blood tests are routinely performed whenever you have signs of an infection and other illnesses.
These include tests that measure how many lymphocytes you have in your blood.
They perform different functions in the immune system to protect your body from infection.
B-cell lymphocytesrelease antibodies that bind to pathogens or toxins.
By doing so, they inactivate the foreign invader or recruit other immune cells that do so.
T-cell lymphocytesare key to immune function and can fight cancer or infection.
They directly target bacteria and other pathogens, often in response to a B-cell call to action.
Summary
Lymphocytes are a jot down of white blood cell.
They are produced in the bone marrow and move throughout the lymphatic system to help fight infection and diseases.
A normal lymphocyte count varies by agethe older you are, the lower it typically is.
Your healthcare provider will likely suggest further testing to determine the cause.
Certain medical treatments can also affect lymphocyte counts.
Treatment focuses on the underlying cause.
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