Low Lymphocytes: Causes, Risk Factors, Symptoms, Diagnosis, Treatment and Prevention

A low count of this type of white blood cell produces a condition called lymphocytopenia.

Lymphocytopenia occurs because:

  • The body does not make enough lymphocytes.
  • The body makes enough lymphocytes, but they are destroyed.
  • Lymphocytes get stuck in the spleen or lymph nodes.
  • A combination of these factors can also cause a low lymphocyte count.

Many diseases, conditions, and factors can lead to a low lymphocyte count. These conditions can be acquired or inherited. “Acquired” means that you were not born with the disease but develop it, and “Inherited” means that your parents passed the gene for the condition to you.

It is unknown how each disease, condition, or factor affects your lymphocyte count. Some people have low lymphocyte counts with no underlying cause.


Acquired causes

Many diseases, conditions, and acquired factors can cause lymphocytopenia. Examples include:

  • Infectious diseases such as AIDS, viral hepatitis, tuberculosis, and typhoid fever.
  • Autoimmune disorders: such as lupus. Autoimmune diseases occur if the body’s immune system mistakenly attacks the body’s cells and tissues.
  • Steroid therapy.
  • Blood cancer and other blood diseases include Hodgkin’s disease and aplastic anemia.
  • Radiation and chemotherapy (cancer treatments).

Inherited causes

Certain inherited diseases and conditions can lead to lymphocytopenia.

Examples include:


  • DiGeorge anomaly.
  • Síndrome de Wiskott-Aldrich.
  • Severe combined immunodeficiency syndrome.
  • Ataxia -langiectasia.

These inherited conditions are rare.

Who is at risk?

People at increased risk for lymphocytopenia have one of the diseases, conditions, or factors that can cause a low lymphocyte count.

This includes people who have:

  • AIDS or other infectious diseases.
  • Autoimmune disorders
  • Blood cancers or other blood diseases.
  • Certain inherited diseases or conditions.
  • People who have received steroid therapy, radiation, or chemotherapy (cancer treatments) are also at higher risk.

What are the signs and symptoms of lymphocytopenia?

A low lymphocyte count alone may not cause any signs or symptoms. The condition is usually found when a person is screened for other diseases or conditions, such as AIDS.

If you have unusual infections, repeat infections, and infections that don’t go away, your doctor may suspect that you have lymphocytopenia. Fever is the most common symptom of the disease.

How is lymphocytopenia diagnosed?

Your doctor will diagnose lymphocytopenia based on your medical history, a physical exam, and test results.

A low lymphocyte count alone may not cause any signs or symptoms. Therefore, the condition is often diagnosed during testing for other diseases or conditions.

Specialists involved

Your primary care doctor may notice that you have unusual, repeated infections that will not go away. These infections can be signs of lymphocytopenia. Your primary care physician can refer you to an infectious disease specialist to determine what is causing the infections.

You can also see a hematologist (specialist in blood diseases) or an immunologist (specialist in immune system disorders). Blood diseases and immune disorders may cause lymphocytopenia.

Medical history

To assess your risk for a low lymphocyte count, your doctor may ask:

  • About your risk for AIDS, including questions about blood transfusions, sexual partners, intravenous (IV) drug use, and exposure to blood or infectious body fluids at work.
  • If you have ever received radiation or chemotherapy (cancer treatments).
  • If you have ever been diagnosed with a blood disease or immune disorder, or if you have a family history of such conditions.

Physical exam

Your doctor will perform a physical exam to check for signs of infection, such as a fever. They may examine your abdomen for an enlarged spleen and your neck for signs of enlarged lymph nodes.

Your doctor will also look for signs and symptoms of diseases and conditions affecting your lymphocyte counts, such as AIDS and blood cancer.

Diagnostic tests

Your doctor may recommend one or more of the following tests to help diagnose a low lymphocyte count.

  • Complete blood count with differential.
  • A complete blood count (CBC) measures many parts of your blood. The test checks the number of red blood cells, white blood cells, and platelets in your blood. The CBC will show if you have a low white blood cell count.

Lymphocytes account for 20 to 40 percent of all white blood cells. Although a CBC will show a low white blood cell count, it will not show if the number of lymphocytes is low.

You may need a more detailed test, called a CBC with differential, to determine if you have a low lymphocyte count. This test shows if you have low levels of certain types of white blood cells, such as lymphocytes. The test results can help your doctor diagnose lymphocytopenia.

Flow cytometry

Flow cytometry (si-TOM-eh-tree) examines many types of blood cells. It is even more detailed than a CBC with differential. Flow cytometry can measure the levels of the different types of lymphocytes: T cells, B cells, and natural killer cells.

The test can help diagnose the underlying cause of lymphocytopenia. Some underlying conditions cause low levels of T cells. Others can cause low levels of B cells or natural killer cells.

Tests for underlying conditions

Many diseases and conditions can cause lymphocytopenia. Your doctor will want to find the cause of the disorder. You may be tested for HIV / AIDS, tuberculosis, blood diseases, and immune disorders.

Tests for these underlying conditions may include blood tests, bone marrow tests, and lymph node tests.

Lymph nodes are part of the immune system. They are found in many places on your body. During a physical exam, your doctor may find that specific lymph node are swollen. The lymph nodes can retain too many lymphocytes in lymphocytopenia instead of releasing them into the bloodstream.

To evaluate a lymph node, you may need to remove it. Removing a lymph node involves minor surgery.

How is lymphocytopenia treated?

You may not need treatment if you have mild lymphocytopenia with no underlying cause. The disorder may get better on its own.

If you have unusual infections, repeated infections, and infections that will not go away due to lymphocytopenia, you will need treatment for the conditions.

If you have a disease or condition causing lymphocytopenia, your doctor will prescribe a treatment for that disease. Treating the underlying problem will help treat the lymphocytopenia.

Treatment for infections

A low lymphocyte count makes it difficult for your body to fight infection. You can get infections caused by viruses, fungi, parasites, or bacteria.

Treatment of infection will depend on its cause. You may also need treatment after an infection has cleared to help prevent repeat infections.

Children with severe and ongoing bacterial infections may be given a medicine called immune globulin. This medicine helps boost the immune system and fight infections.

Treatment of underlying diseases or conditions

Many diseases and conditions can cause lymphocytopenia. Examples include:

  • Infectious diseases like AIDS.
  • Blood diseases such as aplastic anemia.
  • Hereditary diseases such as Wiskott-Aldrich syndrome.

Your treatment will depend on your underlying disease or condition.

Emerging treatments

Researchers are looking for ways to increase lymphocyte production in people with lymphocytopenia with severe underlying conditions.

For example, some studies investigate blood and bone marrow stem cell transplants. This procedure can help treat or cure some conditions that can cause a low lymphocyte count.

Other studies look at drugs and other substances that can help the body make more lymphocytes.

How can lymphocytopenia be prevented?

You can’t prevent lymphocytopenia caused by an inherited condition. However, you can take steps to control lymphocytopenia. Follow your treatment plan and take all medications as directed by your doctor.

Early diagnosis can also help control lymphocytopenia. Newborns should be routinely screened for an immune condition that can lead to lymphocytopenia. This allows doctors to diagnose the disorder before serious problems develop.

You may be able to reduce the risk of acquired conditions that cause lymphocytopenia.

Living with lymphocytopenia

If you have mild lymphocytopenia with no underlying cause, you may not need treatment. The disorder may get better on its own.

If an underlying condition is causing your lymphocytopenia, you will need treatment for that condition. You will also need therapy for infections if your body cannot fight them due to lymphocytopenia.

Treatment and prevention of infections

The main risk of lymphocytopenia is getting unusual, recurring infections that will not go away. If you have the disorder, you may receive treatments to prevent diseases or treat conditions you already have.

Treat an underlying disease or condition.

If you have a disease or condition causing lymphocytopenia, you will need treatment for that condition.

You will likely have regular exams to show how the treatment is working. For example, blood tests may check the number of lymphocytes in your blood.

If treatments for the underlying condition work, the number of lymphocytes in the blood may increase.

Physical activity

Talk to your doctor about what types and amounts of physical activity are safe for you. You may want to avoid activities that could cause injury or increase the risk of infection.