The Pretransplant EASIX Score Predicts Transplant‐Related Mortality in Children Undergoing Hematopoietic Stem Cell Transplantation for Non‐Malignant Disorders

The Endothelial Activation and Stress Index (EASIX) represents a significant advancement in the assessment of risk for pediatric patients undergoing hematopoietic stem cell transplantation (HSCT). While EASIX has been extensively studied in adults, emerging research indicates its potential utility in children. We conducted a retrospective analysis involving 475 pediatric patients with non-malignant diseases who underwent allogeneic HSCT. The primary objective was to explore the correlation between the pretransplant EASIX score (EASIXpre) and transplant-related mortality (TRM) following HSCT. Our study utilized ROC curve analysis to determine an optimal cut-off point at EASIX-pre = 2. Within two years, TRM was 24.6% (95% CI 15.6-38.6) in patients with high EASIX scores, compared to just 7.9% (95% CI 5.7-11.0) in those with low scores (p < 0.001). Additionally, overall survival rates at two years were lower for the high EASIX group: 73.6% (95% CI 62.1-85.1) versus 92.3% (95% CI 89.8-94.9) (p < 0.001). In multivariate analyses, the ROC-optimized cut-off of 2 demonstrated internal consistency in our cohort, confirming its association with TRM. However, this does not represent external validation, which requires independent pediatric cohorts. In conclusion, the EASIX score stands out as a valuable and cost-effective biomarker for predicting transplant outcomes in pediatric patients undergoing allogeneic HSCT for non-malignant diseases.