Prognostic Factors Associated With Increased Mortality in Pediatric Veno-Occlusive Disease Following Hematopoietic Cell Transplantation

Background: Hepatic veno-occlusive disease (VOD) is a life-threatening complication of hematopoietic cell transplantation (HCT) and is categorized as a transplant-related, systemic endothelial disease. Severe VOD can lead to multi-organ dysfunction (MOF) and is associated with a high mortality rate. Objective: To evaluate the incidence of VOD in children after HCT and analyze the outcomes and risk factors associated with increased mortality. Study Design: A retrospective cohort study of 1243 children with malignant and non-malignant diseases who underwent HCT at two large pediatric centers over 20 years. Results: One hundred one patients (8%) developed VOD post HCT. Most patients developed VOD post allogeneic HCT (76%) versus autologous (24%). The incidence of VOD was twice as high in children with malignant diseases compared to non-malignant (68% vs. 32%). A much higher incidence of VOD occurred in patients after a busulfan-based regimen versus total body irradiation-based and treosulfan-based, 73%, 18%, and 1%, respectively. The 100-day survival rate of HCT patients with VOD was 69%. The overall survival rate of the entire group was 50%, showing improvement over the span of the study years, from 40% between 2000 and 2009 to 63% between 2010 and 2021 (p = 0.022). Factors associated with increased mortality included infections before transplant (p = 0.013), conditioning regimen (p = 0.01), abnormal liver function (p = 0.019), presence of ascites (p = 0.008), MOF (p < 0.001), and the need for admission to a pediatric intensive care unit (p < 0.001). There was no significant difference in survival rates between children treated with defibrotide alone or with those treated with defibrotide and steroids (61% and 65%, respectively; p = 0.685). Conclusions: Severe VOD in pediatric patients following HCT remains a life-threatening complication with a high mortality rate. Early diagnosis and treatment with defibrotide are critical for managing this condition. In our cohort, the addition of steroids to defibrotide was not associated with improved outcomes.