Pediatric acute GVHD: clinical phenotype and response to upfront steroids

To better understand the clinical phenotype of acute graft-versus-host disease (GVHD) in children, we examined the GVHD clinical stage, grade, and response to prednisone 60 mg/m²/day PO in a diverse group of 370 pediatric patients with acute GVHD treated from 1990 to 2016 at a single institution. Overall response [complete response (CR) + partial response (PR)] at day 28 occurred in 65%, (CR 52%; PR 13%). Initial GVHD grade did not predict day 28 response. However, the Minnesota GVHD Risk Score predicted response with 68% standard risk (SR)-GVHD patients achieving CR/PR at day 28 versus 48% high risk (HR)-GVHD patients (p < 0.01). Multivariable analysis confirmed that response rates were lower in patients with HR-GVHD [odds ratio (OR), 0.4, p < 0.01] and in recipients of HLA mismatched URD (OR 0.4, p = 0.03). Transplant-related mortality (TRM) at 2 years was greater in HR-GVHD patients, recipients of HLA-partially matched or mismatched unrelated donor (URD) grafts, but not umbilical cord blood (UCB). These data highlight the importance of including children in novel acute GVHD treatment trials. Compared with initial GVHD grade, the Minnesota GVHD Risk Score better demarcates risk of steroid failure and TRM in children and could be used for risk stratification in pediatric acute GVHD studies.