Utility of the Phoenix-8 and PELOD-2 scales in pediatric patients with sepsis and acute lymphoblastic leukemia admitted to a pediatric intensive care unit at a quaternary-level hospital in Bogotá, Colombia, 2022-2024.

Introduction: Sepsis in children with acute lymphoblastic leukemia (ALL) is associated with high mortality and a frequent need for advanced organ support; therefore, reliable scoring systems are required to stratify risk in the pediatric intensive care unit (PICU). Objective: To compare the performance of the Phoenix-8 and PELOD-2 scales, measured at 24 and 72 h after admission, for predicting 28-day mortality in children with ALL and sepsis or septic shock. Methods: A retrospective cohort study including 61 patients aged 1 month to 18 years with ALL admitted to the PICU of a quaternary-level hospital in Bogotá, Colombia, between 2022 and 2024. Phoenix-8 and PELOD-2 scores were calculated at 24 and 72 h after admission. Receiver operating characteristic (ROC) curves, optimal cutoff points, sensitivity, and specificity were analyzed. Results: Twenty-eight-day mortality was 23.0%; 27.9% of patients required invasive mechanical ventilation and 63.9% required vasoactive support. At 72 h, a PELOD-2 score ≥7 showed an area under the ROC curve (AUC) of 0.945, with a sensitivity of 92.9% and specificity of 91.1%. A Phoenix-8 score ≥8 achieved an AUC of 0.976, with a sensitivity of 92.9% and specificity of 91.3%, and was significantly associated with the use of mechanical ventilation, vasoactive agents, and renal replacement therapy. Discussion: Phoenix-8 and PELOD-2 demonstrated moderate discriminative ability at admission but excellent performance at 72 h, making them clinically useful and comparable tools for prognostic stratification in children with ALL and sepsis.