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Quick Facts

Low White Blood Cell Count

(Neutropenia; Lymphopenia)

By

The Manual's Editorial Staff

Last full review/revision Sep 2019| Content last modified Sep 2019
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White blood cells are part of your body's immune system defenses against infection and cancer. Your body has several types of white blood cells. White blood cells are made in your bone marrow.

What is a low white blood cell count?

A low white blood cell count is an unusually low number of one or more kinds of white blood cells.

  • A low white blood cell count puts you at increased risk of infection

  • Some infections can be life-threatening

  • A low white blood cell count is often a side effect of drugs, particularly chemotherapy drugs

  • Sometimes a low white blood cell count is caused by an infection or cancer

  • Doctors may do blood tests and bone marrow tests to see why your white blood cell count is low

  • Doctors may give you medicine to increase your white blood cells and antibiotics if you have a fever or other signs of infection

What causes a low white blood cell count?

There are many causes of a low white blood cell count:

What are the symptoms of a low white blood cell count?

A low white blood cell count has no specific symptoms. You get symptoms because you develop frequent infections. Sometimes the infections are unusual ones that most people don't get.

Symptoms of infections can start suddenly or slowly and can include:

How can doctors tell if my white blood cell count is low?

Doctors can tell you have a low white blood cell count by doing a routine complete blood count (CBC). If you're getting treatments or have a disease that can lower your white blood cell count, doctors check your CBC often.

Sometimes, the cause is obvious, such as if you’re getting chemotherapy or radiation therapy for cancer.

If the cause isn't clear, doctors may do:

  • Blood, urine, and imaging tests looking for infection

  • Bone marrow biopsy (removing some bone marrow with a needle to do tests on it)

How do doctors treat a low white blood cell count?

Doctors treat a low white blood cell count using:

  • Antibiotics to treat any infections

  • Medicines to push your body to make more white blood cells

  • Treatment for any diseases that may be causing the count to be low

NOTE: This is the Consumer Version. DOCTORS: Click here for the Professional Version
Click here for the Professional Version

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