From the Guidelines
For a pediatric patient with sustained severe neutropenia but normal platelet count, hemoglobin, hematocrit, and physical exam, the recommended evaluation should include a complete blood count with differential, peripheral blood smear examination, bone marrow aspiration and biopsy, and immunological testing. The initial workup should focus on ruling out infectious causes through blood cultures, viral studies (particularly for EBV, CMV, HIV), and screening for autoimmune disorders with antineutrophil antibody testing 1. Genetic testing is important to identify congenital neutropenia syndromes such as Kostmann syndrome, cyclic neutropenia, or Shwachman-Diamond syndrome. Nutritional assessment and vitamin B12/folate levels should be checked.
While awaiting diagnosis, prophylactic antibiotics may be considered if neutropenia is severe (ANC <500/mm³), and in some cases, granulocyte colony-stimulating factor (G-CSF) at 5-10 μg/kg/day may be initiated 1. The evaluation pathway is critical because isolated neutropenia with otherwise normal blood parameters suggests either a production problem in the bone marrow specific to neutrophils, increased peripheral destruction, or sequestration issues rather than a global bone marrow failure syndrome. Early diagnosis is essential as some causes require specific interventions to prevent serious infections.
Key considerations in the evaluation include:
- Complete blood count with differential to confirm the severity of neutropenia
- Peripheral blood smear examination to look for any abnormalities in neutrophil morphology
- Bone marrow aspiration and biopsy to assess bone marrow function and rule out any underlying marrow disorders
- Immunological testing to identify any autoimmune causes of neutropenia
- Genetic testing to identify congenital neutropenia syndromes
- Nutritional assessment and vitamin B12/folate levels to rule out any nutritional deficiencies contributing to neutropenia.
It's also important to note that patients with severe congenital neutropenia are at risk of developing myelodysplasia and leukemia, with or without G-CSF treatment, emphasizing the need for careful follow-up and monitoring 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Evaluation Approach
The approach to evaluating a pediatric patient with sustained severe neutropenia, normal platelet count, normal hemoglobin (Hb), normal hematocrit (Hct), and a normal physical exam can be guided by clinical history and physical examination, and does not always require an extensive laboratory evaluation 2.
Classification and Management
Most children with chronic neutropenia can be classified and managed based on history and bone marrow morphology 2. The classification includes:
- Congenital neutropenia syndromes (CNSs)
- Autoimmune neutropenia (AIN)
- Chronic idiopathic neutropenia (CIN) Each of these conditions has different clinical manifestations, treatment, and outcomes 3.
Treatment Options
Treatment options for severe chronic neutropenia include:
- Recombinant human granulocyte colony-stimulating factor (rhG-CSF) therapy, which has been shown to increase circulating neutrophils and reduce infection-related events 4
- Prophylactic antibiotics
- Umbilical cord blood transplantations However, treatment should be reserved for more severely affected patients and not given just because the absolute neutrophil count (ANC) is low 2.
Predictors of Prolonged Neutropenia
Predictors of prolonged neutropenia include:
- Age younger than 18 months
- ANC < 500/mm(3)
- Hemoglobin < 10 gm/dL
- Positive cytomegalovirus (CMV) serology 5
Management of Febrile Neutropenia
In otherwise healthy children and youth with fever and neutropenia, the risk for invasive bacterial infection (IBI) is low, and empiric antibiotics are not typically required 6. However, a thorough assessment, including complete history and physical exam, is indicated, and a blood culture should be performed when the ANC is <0.5 × 10(9)/L. Close follow-up, a repeat complete blood count, and strong anticipatory guidance are recommended 6.