Engraftment Syndrome in Autologous Hematopoietic Stem Cell Transplant Patients: Incidence, Associated Risk Factors, Features, and Outcomes.

BACKGROUND Autologous stem cell transplantation (ASCT) is the standard treatment for multiple myeloma (MM) and refractory/relapsed (R/R) lymphoma patients. Engraftment syndrome (ES) is a non-infectious febrile syndrome during ASCT. This study focused on the incidence, risk factors, manifestations, and outcomes of patients with ES receiving ASCT. MATERIAL AND METHODS This retrospective cohort study included MM and R/R lymphoma patients who underwent ASCT at Chiang Mai University Hospital from January 2014 to September 2020. ES was diagnosed by the consensus of independent reviewers based on clinical manifestations, laboratory, and radiological findings. RESULTS We included 124 patients, of whom 67 (54.1%) had lymphoma. The mean age was 48.0±12.3 years. The incidence of ES was 36.3%. The ES group had a significantly higher proportion of patients with fever, elevated liver enzymes, elevated bilirubin, hypoalbuminemia, and weight gain compared to the non-ES group. TNC more than 10×10⁸ cells/kg was an independent risk factor for ES (odds ratio 2.94 with a 95% confidence interval of 1.15-7.50, P=0.024). ES was associated with longer length of stay (22.5±8.2 vs 16.9±6.4 days, P<0.001) but was not associated with overall survival (OS). CONCLUSIONS The incidence of ES in this cohort was 36.3%. Features observed in ES patients were fever, elevated liver enzymes, elevated bilirubin, and hypoalbuminemia. TNC of more than 10×10⁸ cells/kg was an independent risk factor. ES was associated with longer length of stay but not survival outcomes.