Outcomes of symptomatic venous thromboembolism after haploidentical donor hematopoietic stem cell transplantation and comparison with human leukocyte antigen-identical sibling transplantation.

BACKGROUND: Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is regarded as a curative therapy for majority of hematologic malignancies and some non-malignant hematologic diseases. Venous thromboembolism (VTE) has become increasingly recognized as a severe complication following allogeneic hematopoietic stem cell transplantation (allo-HSCT). OBJECTIVES: To show the characteristics of VTE after haploidentical donor hematopoietic stem cell transplantation (HID-HSCT) and make comparisons with matched related donor HSCT (MRD-HSCT). PATIENTS/METHODS: A retrospective nested case-control study design was used, cases with VTE and matched controls were selected, with 3534 patients underwent HID-HSCT and 1289 underwent MRD-HSCT. RESULTS: During follow-up, 114 patients with VTE were identified. The incidence of VTE in HID-HSCT group was similar to that of MRD-HSCT group (2.4% versus 2.3%, P = 0.92). In HID-HSCT group, VTE occurred at a median time of 92.5 days, which was earlier than MRD-HSCT group (243.5 days). For HID-HSCT, advanced disease status, cardiovascular risk factors, acute graft-versus-host disease (aGVHD), and relapse were the independent risk factors for VTE. For MRD-HSCT, cardiovascular risk factors, aGVHD, and relapse were associated with VTE. Overall survival (OS) of patients following HID-HSCT and MRD-HSCT were similar, but the OS in patients with VTE was significantly lower than patients without VTE. CONCLUSIONS: There was no statistical difference in the incidence of VTE after HID-HSCT compared with MRD-HSCT. The development of VTE adversely impacted the OS after allo-HSCT.

Comparison of different cytomegalovirus diseases following haploidentical hematopoietic stem cell transplantation.

Cytomegalovirus (CMV) can cause end-organ diseases including pneumonia, gastroenteritis, retinitis, and encephalitis in hematopoietic stem cell transplantation recipients. Potential differences among different CMV diseases remain uncertain. This study aimed to compare the clinical characteristics, risk factors, and mortality among different CMV diseases. A retrospective nested case-control study was performed based on a cohort of 3862 patients who underwent haploidentical hematopoietic stem cell transplantation at a single-center. CMV diseases occurred in 113 (2.92%) of 3862 haplo-HSCT recipients, including probable CMV pneumonia (CMVP, n = 34), proven CMV gastroenteritis (CMVG, n = 34), CMV retinitis (CMVR, n = 31), probable CMV encephalitis (CMVE, n = 7), and disseminated CMV disease (Di-CMVD, n = 7). Most (91.2%) cases of CMVG developed within 100 days, while most (90.3%) cases of CMVR were late onset. Refractory CMV infection and CMV viral load at different levels were associated with an increased risk of CMVP, CMVG, and CMVR. Compared with patients without CMV diseases, significantly higher non-relapse mortality at 1 year after transplantation was observed in patients with CMVP and CMVR, rather than CMVG. Patients with CMVP, Di-CMVD, and CMVE had higher overall mortality after diagnosis than that of patients with CMVG and CMVR (61.7%, 57.1%, 40.0% vs 27.7%, 18.6%, P = 0.001). In conclusion, the onset time, viral dynamics, and mortality differ among different CMV diseases. The mortality of CMV diseases remains high, especially for CMVP, Di-CMVD, and CMVE.