Pericardial Effusion after Hematopoietic Stem Cell Transplant Is Associated with Poor Survival

Abstract

<h3>Background</h3> Pericardial effusion (PE) is a rare but life-threatening complication that can occur following hematopoietic stem cell transplant (HCT). The incidence in pediatric post-HCT population has been reported to be between 9%-37%. The underlying etiology is unclear and small studies have reported high morbidity and mortality in patients who develop PE post-HCT. Various studies have attempted to analyze the risk factors associated with occurrence of PE after HCT but detailed analysis is limited due to low incidence. <h3>Methods</h3> We retrospectively analyzed the University of Minnesota's Blood and Marrow Transplant database for occurrence of PE after HCT in patients less than 18 years between January 1, 2005 and December 31, 2018. Data was analyzed to compare the overall survival (OS) in patients who developed PE with those who did not. Risk factors analyzed included age, graft versus host disease (GVHD), type of conditioning regimen, graft source, underlying disease and human leukocyte antigen matching using univariate analysis. Multivariate analysis was performed using logistic regression model. <h3>Results</h3> A total of 770 patients underwent HCT during the study period, of which 162 (21%) developed PE. The median age of transplant for patients who developed PE was 8 years with about 60% males (n=98). Median time to development of PE after HCT was 69 days. Children who developed PE post-HCT had a significantly poor survival (2-year OS of 66%, confidence interval (CI): 58-73% vs 78%, CI: 75-81% in controls; p<0.01). There was a higher risk of grade III-IV acute GVHD in the PE cohort (relative risk (RR) of 14% (CI: 8-19%) vs 4%(CI: 3-6%) in those without PE). In univariate analysis, use of myeloablative conditioning as compared to non-myeloablative or reduced intensity conditioning (RR of 24% (CI: 20-27%) vs 11% (CI: 7-16%); p<0.01), use of umbilical cord blood (UCB) stem cells compared to bone marrow or peripheral blood stem cells (RR: 24% (CI: 20-28%) vs 18% (CI: 14-21%); p<0.01), and underlying malignant disorders were significantly associated with development of PE (RR: 26% (CI: 20-31%)) and inherited metabolic disorders (RR: 23% (CI: 17-28%) vs 15% in non-malignant disorders (CI: 11-20%); p<0.01). A higher risk was also noted in those with metabolic disorders (In multivariate analysis, use of myeloablative conditioning showed a significantly higher risk of development of PE (hazard ratio of 2.16 (CI: 1.33-3.50); p<0.01). <h3>Conclusion</h3> Pericardial effusion after HCT is associated with a higher mortality and higher risk of severe acute GVHD. The high-risk group (underlying malignancy, receiving myeloablative conditioning and UCB transplant) should be monitored closely for development of PE.