Outcomes of Isolated Neutropenia Referred to Pediatric Hematology-Oncology Clinic.

BACKGROUND: Children with isolated neutropenia (absolute neutrophil count [ANC] METHODS: We performed a 5.5-year institutional review board–approved retrospective chart review of children referred to our pediatric hematology and oncology clinics for isolated neutropenia. Neutropenia was categorized as mild (ANC of 1001–1500/μL), moderate (ANC of 500–1000 μL), severe (ANC of 201–500/μL), or very severe (ANC of ≤200/μL). RESULTS: Among 155 children referred with isolated neutropenia, 45 (29%) had mild neutropenia, 65 (42%) had moderate neutropenia, 30 (19%) had severe neutropenia, and 15 (10%) had very severe neutropenia. Only 29 (19%) children changed to an ANC category lower than their initial referral category. At a median follow-up of 12 months, 101 children had resolution of neutropenia, 40 children had mild neutropenia, 10 children had moderate neutropenia, 3 children had severe neutropenia, and 1 patient had very severe neutropenia. A specific diagnosis was not identified in most (54%) children. The most common etiologies were viral suppression (16%), autoimmune neutropenia (14%), and drug-induced neutropenia (8%). Black children had a 3.5 higher odds of having persistent mild neutropenia. Six (4%) children received granulocyte colony-stimulating factor therapy. CONCLUSIONS: Most children referred for isolated neutropenia do not progress in severity and do not require subspecialty interventions or hospitalizations.