Leukapheresis, rasburicase, and acute complications of hyperleukocytosis in pediatric leukemia: A retrospective cohort study.

INTRODUCTION

Hyperleukocytosis is associated with inferior clinical outcomes and early mortality. Leukapheresis provides a rapid reduction in the cell mass, which can cause complications known as leukostasis. This study evaluated the impact of leukapheresis versus standard medical therapy on acute short-term complications, specifically tumor lysis syndrome (TLS) and acute kidney injury (AKI).

METHODS

This single-center retrospective cohort study included 50 pediatric patients with hyperleukocytosis, admitted to the pediatric intensive care unit (PICU) between 2008 and 2023. Patients were grouped according to treatment exposure(standard therapy vs. therapeutic leukapheresis). Data collected included patient demographics, clinical and laboratory data, treatment modalities, and outcomes.

RESULTS

The incidence of TLS and AKI was similar between groups. After multivariable adjustment, leukapheresis was not independently associated with either AKI or TLS. Rasburicase administration emerged as a strong independent protective factor against TLS (OR: 0.057, 95% CI: 0.010-0.310, p = 0.001). Furthermore, TLS was identified as a major independent risk factor for AKI (OR: 28.81, 95% CI:3.779-219.697, p = 0.001). Crude overall mortality was higher in the leukapheresis group (44%) than in the standard-therapy group (16%)(p = 0.046). However, the leukapheresis group also had higher admission WBC counts, lower platelet counts, and older age, findings consistent with confounding by indication. The leukapheresis group also had longer PICU stays and a higher incidence of hypocalcemia and other complications.

CONCLUSIONS

In this retrospective cohort, leukapheresis effectively reduced the white blood cells but was not independently associated with a lower incidence of TLS or AKI.The higher crude mortality in the leukapheresis arm likely reflects baseline disease severity rather than a direct treatment effect.