Sinusoidal Obstruction Syndrome for Stem Cell Transplant Patients Biomarker Study

This is a multicenter, prospective, observational trial. We will measure biomarkers and determine thresholds that will predict increased risk for SOS in pediatric patients receiving HCT or high intensity chemotherapy/irradiation with the future goal of a randomized, interventional, open-label, multicenter trial that will test the preemptive use of defibrotide for prevention of SOS in an enriched high-risk population.