Internal Evaluation of Risk Stratification Tool Using Serial Procalcitonin and Clinical Risk Factors in Pediatric Febrile Neutropenia: The Non-interventional, Single Institution Experience Prior to Clinical Implementation

Risk stratification of pediatric febrile neutropenia (FN) is an established concept, yet clinical risk tools misclassify nearly 5% of clinical standard-risk episodes with severe outcomes. The internal evaluation of a clinical risk tool before implementation has not been well-described. In this noninterventional cohort study, we evaluated a study decision rules (SDR) tool; a clinical risk tool with serial procalcitonin. The study standard-risk (SSR) group met clinical standard-risk criteria with two serial procalcitonin <0.4 ng/mL. The study high-risk (SHR) group met clinical high-risk criteria or clinical standard-risk with a procalcitonin ≥0.4 ng/mL. Descriptive and bivariate statistics compared the groups and outcomes. Clinical criteria alone identified 39.1% (238/608) standard-risk episodes; 5.9% (14/238) had severe events. Prospectively using the SDR, the SHR group encompassed 76.6% (92/120) of episodes; severe events occurred in 20% (3/15) of standard-risk episodes included due to elevated procalcitonin ≥0.4 ng/mL. The SHR group had more blood stream infections [21.7% (20/92) vs. 0% (0/28);  = 0.007] and intensive care admissions [13% (12/92) vs. 3.6% (1/28);  = 0.158]. In conclusion, the SDR with serial procalcitonin aided in identifying severe events in clinical standard-risk episodes, but analysis was limited. Institutions may consider similar internal evaluation methodology before FN episode risk stratification.