Veno‐Occlusive Disease in Very Young Children: A Profile of High Morbidity With Low Mortality

Younger age is a recognized risk factor for veno-occlusive disease (VOD), yet no prior studies have focused on diagnostic criteria and outcomes in very young children. This retrospective study compared overall survival (OS) in very young children with and without a clinical diagnosis of VOD, in addition to comparing OS for those with clinical VOD versus those who retrospectively fulfilled VOD criteria. Included were patients who received their first hematopoietic stem cell transplant (HCT) for any indication at less than 4 years of age between January 1, 2016 and October 31, 2021. Three pediatric VOD criteria were retrospectively applied to subjects. Of 150 HCT recipients less than 4 years old, 18 were clinically diagnosed with VOD at a median of 14 days. More patients with VOD were admitted to the ICU [79% vs. 15%, p < 0.001]. Of those with VOD, 78% required peritoneal drainage, 17% pleural effusion drainage, and 56% respiratory failure. All patients with VOD survived to discharge and to Day +100. In allo-recipients, OS at Day +365, cumulative incidence of Grade II-IV acute graft-versus-host disease (aGVHD) at Day +100, and chronic graft-versus-host disease (cGVHD) at Day +365 were similar between those with and without VOD. Median length of stay was longer in those with VOD [60.5 vs. 38 days, p < 0.001]. More patients retrospectively met criteria for VOD than were clinically diagnosed. While VOD in very young children can be highly morbid, they have excellent early survival. Retrospective evaluation demonstrates that only some patients who fulfilled VOD criteria were clinically diagnosed.