Reduced intensity allogeneic umbilical cord blood transplantation in children and adolescent recipients with malignant and non-malignant diseases.

There is a significant amount of morbidity and mortality following myeloablative umbilical cord blood transplantation (UCBT). Reduced intensity (RI) conditioning offers an alternative to myeloablative conditioning before UCBT. We investigated RI-UCBT in 21 children and adolescents with malignant (n=14), and non-malignant diseases (n=7). RI conditioning consisted of fludarabine (150-180 mg/m2) with either busulfan (< or = 8 mg/kg)+rabbit antithymocyte globulin (R-ATG; n=16) or cyclophosphamide+R-ATG+/-etoposide (n=5). Human leukocyte antigen match: 4/6 (n=13), 5/6 (n=5) and 6/6 (n=3). The median total nucleated cell and CD34+ cell dose per kilogram were 3.58 x 10(7) and 2.54 x 10(5), respectively. The median time for neutrophil and platelet engraftment was 17.5 and 52 days, respectively. There were six primary graft failures (chronic myelogenous leukemia (CML), beta-thalassemia, hemophagocytic lymphohistiocytosis (HLH) and myelodysplastic syndrome (MDS)). The probability of developing grade II to grade IV acute graft-versus-host disease (GVHD) and chronic GVHD was 28.6 and 16.7%, respectively. Incidence of transplant-related mortality (TRM) was 14%. The 5 years overall survival (OS) in all patients was 59.8%. The 5 years OS for patients with average versus poor-risk malignancy was 77.8 versus 22.2% (P=0.03). RI-UCBT may result in graft failure in specific high-risk chemo-naïve patients (CML, beta-thalassemia, HLH and MDS), but in more heavily pretreated pediatric and adolescent recipients results in rapid engraftment and may be associated with decreased severe GVHD and TRM.

Pericardial effusion post-SCT in pediatric recipients with signs and/or symptoms of cardiac disease.

The objective of this study was to assess the incidence, risk factors, outcome and impact on OS of pericardial effusion (PEF) in a cohort of 156 pediatric SCT recipients. The mean age was 8.15±6.25 years. In all, 74% of the patients had malignant disease and 35% of the patients received autologous stem cell grafts. Twenty-three subjects developed effusion at 2.75±3.54 months after SCT. The overall probability of developing a PEF after SCT was 16.9%. In the multivariate analysis of risk factors associated with time to PEF, increased age, allogeneic risk status and conditioning type, were all significant factors. In a multivariate analysis of time to death, PEF, CMV status and risk status were all independent risk factors. PEF, however, had the highest HR of 3.334. Of the 23 patients with PEF, 19 died (82.6%); however, none died as a direct result of pericardial tamponade. In summary, our results suggest that PEF is a significant risk factor for post transplant mortality. These results suggest a need for more frequent evaluation and monitoring for development of PEF. Studies are needed to determine the etiology of, and new therapeutic strategies for, PEF in the post-SCT population.