What virus causes low neutrophils?

Neutropenia happens when a child has low levels of a type of white blood cell called a neutrophil.

There are many types of white blood cells. Their job is to fight infection. Neutrophils surround and destroy harmful bacteria and viruses.

Neutropenia can happen if:

  • Your child’s body does not make enough neutrophils
  • Neutrophils are destroyed after they are made
  • Neutrophils collect in a certain spot in the body instead of moving through the bloodstream

Having slightly lower neutrophil levels may be normal in children of African, Middle Eastern or West Indian descent. This is called “constitutional neutropenia” and rarely needs treatment.

  • The most common causes in children are:

    • A temporary decrease in the number of white blood cells in the bone marrow
    • An increase in the number of white blood cells being destroyed after a viral infection. It can take a lot of white blood cells to fight a viral infection. The level of neutrophils can fall quite low and may stay low for many months. Most of the time, this type of neutropenia does not raise the risk of serious infections much. It usually gets better on its own over time.

    Other possible causes for neutropenia include:

    • A child’s immune system attacking their own blood cells.
    • Getting chemotherapy medicines for cancer.
    • Taking certain other medicines that reduce how many neutrophils your child’s body makes.
    • Not getting enough of some vitamins, such as B12. This may reduce the number of blood cells being made.
    • Blood diseases or problems with the bone marrow, like aplastic anemia, that can cause low blood cell levels.
    • Certain conditions passed from parents to children (inherited).
    • Some infections that can reduce blood cell levels, such as tuberculosis (TB).

What virus causes low neutrophils?
We offer a full range of services to diagnose and treat children with this condition. Our experience helps us know what to watch for and how to prevent and treat problems early. This increases the chances of successful treatment and helps your child feel better.

If you would like an appointment, ask your primary care provider to refer you to our Cancer and Blood Disorders Center. If you have a referral or would like a second opinion, contact the center at 206-987-2106.

Providers, see how to refer a patient.

  • The experts you need for accurate diagnosis and care

    Our doctors are nationally known for treating children who have blood disorders. The doctors who will guide your child’s care are board certified in pediatric hematology. This means they are approved to give the special care your child needs and they constantly expand their knowledge about blood disorders.

    Our team has the skills and experience to find the cause of your child’s neutropenia.

    • If your child has a bone marrow disorder or a condition that was passed from parents (inherited), our Bone Marrow Failure team will care for them.
    • For an immune system disorder, your child will get expert care from specialists at our Immunology Clinic. The clinic has over 40 years of experience diagnosing and treating children.
    • Genetic counseling can be helpful if your child may have an inherited condition.
    • Our infectious disease team can help manage infections that may arise due to neutropenia.
    • Very rarely, children with neutropenia need a stem cell transplant to help their body make healthy blood cells. Our Non-Malignant Transplant Program will care for your child if they need this treatment.

    We help your child stay healthy and fight infections that happen. Your family has a full team behind you. Your child’s team will include doctors, nurses, social workers and other specialists as needed, such as nutritionists. Read more about the supportive care we offer. 

  • Among the nation’s best children’s hospitals

    Our specialty is treating children’s disease while helping them grow up to be healthy and productive.

    Our physician-scientists help set national standards for care of young people with blood disorders. We provide the most advanced treatments in our region.

    Children don’t react to illness, injury, pain and medicine in the same way as adults. They need – and deserve – care designed just for them. Our experts focus on how treatments today affect growing bodies in the future. We plan your child’s treatment based on years of experience plus the newest research on what works best – and most safely – for children.

  • Support for your whole family

    Having a child with neutropenia can be stressful. We take positive steps right away by offering same-day appointments for children with urgent needs, such as fever. If needs are not urgent, most new patients are seen within 1 or 2 weeks.

    During visits, we take time to explain your child’s condition. We help you fully understand your treatment options. Our experience helps us recommend the right treatment at the right time to have the best results for your child and your family.

    Our child life specialists and social workers help your child and your family through the challenges of this condition. We connect you to community resources and support groups.

    At Seattle Children's, we work with many children and families from around the Northwest and beyond. Whether you live nearby or far away, we can help with financial counseling, schooling, housing, transportation, interpreter services and spiritual care. Read about our services for patients and families.

Children with low levels of neutrophils may show no symptoms until they start having infections. Fever is a common sign of infection. Other symptoms depend on where the infection is:

  • Ear infections cause pain in the affected ear.
  • Sinus infections may cause headache, congestion or cough.
  • Pneumonia is a lung infection and may cause chills, coughing, shortness of breath and muscle aches.
  • A urinary tract infection may cause fever, nausea or pain when peeing.
  • Sores in their mouth or red, swollen (inflamed) gums are signs of infection in the mouth.
  • Skin infections may cause a rash or itching.

Diagnosing Neutropenia

The doctor may suspect a problem with white blood cells, like neutrophils, if your child gets frequent or uncommon infections (such as an infection in the blood) or has inflamed gums for no clear reason.

To diagnose neutropenia, your child’s doctor will take a blood sample to check the levels of each type of blood cell. This is called a complete blood count.

Other tests can help us understand why your child has low neutrophils. Depending on your child’s symptoms, doctors may:

  • Get a sample of bone marrow by doing a bone marrow aspiration or biopsy
  • Test the blood for antibodies against neutrophils
  • Check how your child’s immune system is working
  • Check levels of vitamin B12 and folate.
  • Look for changes in genes that indicate an inherited marrow failure disorder

The doctor may check your child's blood cell levels from time to time if your child’s treatment for another illness may cause neutropenia. For example, chemotherapy to treat cancer can cause neutropenia. Regularly checking blood cell levels helps find neutropenia early. Doctors may be able to treat it before infections increase.

Neutropenia does not always need treatment. It depends on how severe the condition is and what caused it. Even if doctors cannot pin down the cause, we can help manage the neutropenia to avoid problems.

Most often children get neutropenia after fighting off an infection caused by a virus. With time, their bodies will build up their neutrophil level again. Until then, your child will need care for any infection they get.

If your child’s neutropenia is caused by a disease of the blood, bone marrow or immune system, we will treat the underlying cause. Read more about our programs to treat bone marrow failure and immune system disorders.

Your child’s care plan depends on their illness. We watch your child closely and recommend the best treatment options.

  • Preventing and treating infection

    Your child's doctor will suggest ways to help avoid infection, such as:

    • Frequent handwashing
    • Avoiding crowds and limiting contact with sick people
    • Getting all recommended vaccines
    • Good care of teeth and regular dental checkups to avoid problems with gums

    Fever (over 38.5° C or 101.3° F) is a sign of infection and needs attention right away. We will give you guidelines about what to do if your child gets a fever.

    They may need antibiotics to help fight infections caused by bacteria. Usually, antibiotics are given into your child’s vein using a tube called an IV (intravenous) line.

    A child who gets an infection may need to stay in the hospital until we are sure their infection is controlled.

  • For more severe neutropenia that has led to infections or severe gum disease, we may suggest giving your child injections of a neutrophil growth factor. This boosts the number of white blood cells your child's body makes. It is given as a shot under the skin.

  • Very rarely, treatment for neutropenia includes an infusion of blood-forming stem cells from a healthy donor. This treatment is called a stem cell transplant or bone marrow transplant. It helps bone marrow make healthy blood cells.

    If this treatment may be an option for your child, we will talk with you about:

    • The risks and benefits
    • Whether a stem cell transplant fits with your family’s values, goals and priorities

    Our Non-Malignant Transplant Program specializes in stem cell transplants for children with blood disorders and other noncancer conditions. We perform the transplants here at Seattle Children’s, working closely with our partner Fred Hutch. Fred Hutch pioneered stem cell transplants and is one of the largest stem cell transplant centers in the world.

Contact Us

If you would like an appointment, ask your child’s primary care provider to refer you.

If you have a referral or would like a second opinion, call the Cancer and Blood Disorders Center at 206-987-2106.

Providers, see how to refer a patient.

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