How should a primary care physician evaluate neutropenia, and decide when it’s time to worry? Kandace Gollomp, MD, pediatric hematologist, Children’s Hospital of Philadelphia, discusses: tips for evaluating a CBC with differential; absolute neutrophil count (ANC) parameters for mild/moderate/severe neutropenia; when to worry about increased risk of infection, both in previously well children and in those with risk factors; a review of risk factors; lymphopenia, granulocytopenia and agranulocytosis and how they are different; benign ethnic neutropenia; post-infectious neutropenia and when you should re-check the CBC; when an infectious history should raise a red flag; when to order a peripheral smear or refer a patient to hematology for bone marrow biopsy or other evaluation; and more.  Published February 2022. This podcast is for general informational and educational purposes only and is not to be considered as medical advice for any particular patient. Clinicians must rely on their own informed clinical judgment in making recommendations to their patients. ©2022 by Children's Hospital of Philadelphia, all rights reserved.