Lymphocytes are an important part of the immune system and lymphopenia increases your risk of infections.

When treatment is needed, it will depend on the underlying cause.

This article explains lymphopenia, its causes, and how it’s diagnosed and treated.

Close up of scientists hands selecting a blood sample for medical testing

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What Are Lymphocytes?

This is followed bythrombocytes(platelets) and leukocytes (white blood cells).

What Causes Lymphopenia?

Lymphopenia can be triggered by many conditions, including infection, poor nutrition, and medication side effects.

At times, the condition may only affect lymphocytes.

In others, it can be the result of a depletion of all white blood cells.

When lymphopenia is related to an infection, it is considered pathogenic.

Infections may kill off white blood cells faster than they can be produced or temporarily disrupt bone marrow.

In others, it can affect the entire range of white blood cells (leukopenia).

Nutritional Deficiencies

Not eating enough protein, vitamins, or minerals can cause lymphopenia.

Poor nutrition is a major risk factor for lymphopenia worldwide.

Inherited Conditions

Inherited conditions that involve diminished bone marrow function can cause lymphopenia.

A low count is rarely an unexpected finding.

At other times, you may need additional tests to piece together a cause.

Your provider may also test your bone marrow or yourlymph nodes.

What Is a Low Level of Lymphocytes?

Adults may be diagnosed with lymphopenia if they have less than 1,500 lymphocytes per microliter of blood.

For children, it varies based on their age.

How Do You Treat Lymphopenia?

Mild cases of lymphopenia may resolve on their own without treatment.

This may include treatments for particular infections, cancers, or autoimmune disorders, for example.

It puts you at risk of new infections and getting sick.

Poor diet or heavy drinking can also lead to it.

If treatment is needed, it will target the underlying cause.

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