Rapid Absolute Neutrophil Count Testing Guides Targeted Antimicrobial Therapy in Febrile Pediatric Oncology Patients.

Objectives: It is well established that early antibiotic administration leads to improved outcomes in febrile neutropenic patients. To achieve this, many institutions administer empiric antibiotics to all febrile oncology patients in the emergency setting, before knowing their neutropenic status. This study evaluates the role of rapid absolute neutrophil count (ANC) testing in the targeted antimicrobial management of nonneutropenic febrile oncology patients.

Methods: We conducted a retrospective review of patients 19 years or younger presenting to the pediatric emergency service with an oncologic process and fever or history of fever. We examined the administration of antibiotics and outcomes in nonneutropenic patients.

Results: We included 101 patient encounters, representing 62 distinct patients. The rapid ANC test influenced antibiotic management in 94% (95/101) of patient encounters and resulted in no antibiotics or targeted antibiotic therapy in 88% (60/68) of nonneutropenic patients. Use of the rapid ANC test to guide treatment would have spared antibiotic administration in 68% (46/68) of well-appearing nonneutropenic patients with no alternate indication. No well-appearing, nonneutropenic patient had a positive blood culture, and only 1 required hospital admission on a repeat visit.

Conclusions: The rapid ANC is a useful tool to balance the goal of early antibiotic administration in febrile neutropenic oncology patients while promoting antibiotic stewardship in this vulnerable population.