The EASIX score as a predictor of sinusoidal obstruction syndrome and nonrelapse mortality in paediatric patients receiving allogeneic haematopoietic stem cell transplantation

The endothelial activation and stress index (EASIX) score, calculated as [lactate dehydrogenase (LDH; U/L) × serum creatinine (mg/dL)]/platelets (10e9/L)], has been shown to be predictive of nonrelapse mortality (NRM) and endothelial complications in adults receiving allogeneic stem cell transplantation (allo-HSCT); however, definitive results are lacking for children. We retrospectively evaluated consecutive paediatric allo-HSCT recipients and calculated the log2 EASIX score every day from admission to day +35. In 167 allo-HSCT recipients, the EASIX score increased from before conditioning (-0.79) to a maximum score on day +20 (2.23). In multivariate analysis, the EASIX score at day +7 was an independent predictor of sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD) (OR 1.52; 95% CI, 1.08-2.13; p = 0.017) and NRM (OR 1.68; 95% CI 1.16-2.42; p = 0.006). At several time points between day +0 and day +14, the EASIX score was independently associated with NRM, with the strongest predictive power being observed on day +12 (OR 3.05; 95% CI, 1.53-6.10; p = 0.002). Age correlated linearly with the EASIX score at all analysed time points, but score prediction was confirmed even when age was added to the multivariate model, indicating that age was not a confounding factor in the observed associations. The EASIX score determined shortly after transplantation can be further explored as a predictor of SOS/VOD and NRM in paediatric allo-HSCT recipients.