An Overview of Pediatric Neutropenia

Pediatric neutropenia is an uncommon condition that causes a low count of white blood cells called neutrophils in babies and children. This type of cell help prevent infection. There are several potential causes, including viruses, an autoimmune condition, cancer treatment, and others.

Neutropenia is more common in infancy and early childhood with rates dropping as a child grows.

This article discusses the types of pediatric neutropenia and what causes them. It also reviews symptoms, the diagnostic process, treatment options, and the prognosis for children with this condition.

Types of Pediatric Neutropenia

The type of neutropenia affecting a child factors into how long it may last, how it can be treated, and more. Pediatric neutropenia types include acute, cyclic, congenital, autoimmune, and chronic idiopathic neutropenia.

Acute Neutropenia

A viral infection is the most common reason for pediatric neutropenia. The body uses up white blood cells to fight the infection, temporarily lowering a child's count.

White blood cell levels should return to normal once the child recovers. This usually takes six weeks or less.

Cyclic Neutropenia

With this type, low neutrophil counts are only present for three to six days every three weeks (on average).

Cyclic neutropenia can affect children and adults, and more than one person in a family is likely to have it. In children, the condition usually begins to improve after puberty.

Congenital Neutropenia

This type of neutropenia is inherited and tends to be the most severe. It is the most common type in children younger than 4 and is usually diagnosed when the child develops a life-threatening bacterial or fungal infection.

Autoimmune Neutropenia (Chronic Benign Neutropenia of Childhood)

With autoimmune neutropenia (AIN), bone marrow makes neutrophils as it should, but the body incorrectly makes antibodies to neutrophils that mark them for destruction.

Autoimmune neutropenia is often diagnosed around 7 to 9 months of age. Fortunately, it disappears on its own in most children within two years.

Autoimmune neutropenia that occurs in combination with immune thrombocytopenia (ITP) or autoimmune hemolytic anemia (AIHA) is called Evans Syndrome.

Chronic Idiopathic Neutropenia

This type is referred to as idiopathic because there is no known cause. 

Causes of Pediatric Neutropenia

Pediatric neutropenia can have a number of causes. These can include:

• A bacterial infection such as tuberculosis
• A viral infection such as mononucleosis
• An autoimmune condition that causes the immune system to mistakenly destroy neutrophils
• Abnormal bone marrow production, which can happen as a result of a condition such as aplastic anemia or leukemia
• Radiation therapy or chemotherapy as a part of cancer treatment can destroy neutrophils
  

And with the idiopathic type, the cause is unknown.

Rates of neutropenia vary based on a child's ethnicity and where they live in the world.

In the United States, the rate of neutropenia is 7.2% for children under 2 years old and 3.7% for those ages 3 to 5. It drops to 2.3% for 6- to 8-year-olds.

Globally, the condition is most prevalent among children in North African and Arab nations, affecting about 15.4% of children under 6 years of age.

Pediatric Neutropenia Symptoms

Despite the exceptionally low neutrophil count that defines pediatric neutropenia, serious infections are rare. As a result, the condition may not cause profound symptoms. Most children have no symptoms at all.

However, you may notice that your child:

• Gets colds, ear infections, or sinus infections often; symptoms such as fever, sore throat, coughing, diarrhea, congestion, and chills are common when sick
• Gets urinary tract infections or infections of the reproductive tract
• Develops mouth sores, gum infections, or gum disease
• Gets skin infections and/or does not heal quickly

In these cases, neutropenia may be discovered when a complete blood count (CBC) is done to diagnose an infection.

Diagnosis

A CBC is the first diagnostic test that will be done. This is a blood test that reports on several blood components.

With pediatric neutropenia, the absolute neutrophil count (ANC) is typically below 1000 cells per microliter and can be below 500. Usually, the hemoglobin and platelet count are normal.

A peripheral blood smear may also be done. This is an examination of the blood cells under a microscope. Although the number of neutrophils is low, they usually look normal.

Next, a healthcare provider will likely obtain CBCs twice weekly for at least six weeks. This is done to ensure that your child does not have cyclic neutropenia.

Additional Testing

Your physician may order additional testing to determine if there are antibodies to the neutrophils. A positive result confirms autoimmune neutropenia. Unfortunately, a negative result doesn't rule it out.

In some patients, anti-neutrophil antibodies are never identified. In these cases, if the age and presentation fit the picture of autoimmune neutropenia, the diagnosis is presumed.

In rare cases, a bone marrow biopsy might be necessary to rule out other causes of neutropenia. This typically occurs in children whose presentation and infections don't fit the typical picture of pediatric autoimmune neutropenia.

Pediatric Neutropenia Treatment

There is no specific treatment for neutropenia. If a child with the condition develops a fever, they will typically undergo a CBC. Your child's healthcare provider may also order a blood culture. During this test, a blood sample is placed in a glass bottle and checked for bacteria. Your child will also receive at least one dose of antibiotics.

If the ANC is less than 500 cells/mL, your child will likely be admitted to the hospital on IV antibiotics for observation. Sometimes filgrastim (G-CSF) can be used during active infections to stimulate the release of neutrophils from bone marrow to blood circulation.

If your child looks well and the ANC is greater than 1,000 cell/mL, they will likely be sent home for outpatient follow-up.

If your child has autoimmune neutropenia, the anti-neutrophil antibodies will spontaneously disappear and the neutrophil count will return to normal. Spontaneous recovery occurs by years of age, with neutropenia lasting on average 20 months.

Medications used for other immune blood disorders like steroids and intravenous immune globulin (IVIG) are not as successful in autoimmune neutropenia.

Prognosis

Most children with neutropenia do not become seriously ill. Still, your healthcare provider will want to be cautious. Any fever or infection in a child with neutropenia should be evaluated by a healthcare provider.

Most of the time, neutropenia is a disease of childhood that resolves on its own before adulthood.

Summary

Pediatric neutropenia is a potentially serious condition that affects bacteria-fighting white blood cells called neutrophils. Children with this condition have low levels of neutrophils in their blood. This can lead to more frequent infections, which can sometimes be life-threatening.

Children with neutropenia may be diagnosed after a complete blood count is done as part of a diagnosis for a condition such as an ear or skin infection. Children with neutropenia are carefully monitored and may receive antibiotics or be admitted to the hospital for observation when they develop a fever.

Fortunately, neutropenia often resolves as a child gets older.