Second Allogeneic Stem Cell Transplantation (SCT) In Pediatric Patients
Biology of Blood and Marrow Transplantation
Methods: The surveyed centers accounted for 75% of all pediatric HSCT and were identified by querying the CIBMTR. Two individuals from each of these institutions were survey recipients; one from the Division of Pediatric Critical Care Medicine (PCCM) and the other from the Division of HSCT. The survey was conducted electronically using SurveyMonkey allowing data to remain anonymous. A four-choice Lickert scale was used for clinical questions. Results: Completed surveys were returned from both
... eturned from both the HSCT and PCCM physicians in 22 programs. The percentage of programs that always or commonly perform the following interventions on the HSCT unit are as follows: central venous pressure monitoring (18%), 100% non-rebreather mask (50%), non-invasive ventilation(18%), intermittent hemodialysis (41%), continuous venovenous hemofiltration (0%), dopamine (36%) with the maximal dose varying by center. In terms of care by PCCM physicians, most all programs use 100% oxygen, non-invasive ventilation and aggressive diuresis prior to intubation; 2/3 of programs attempt renal replacement therapy (RRT). 59% of PCCM physicians always or commonly offer intubation as a time limited trial to HSCT patients; 18% never offer this option. Non-conventional respiratory therapies commonly offered to HSCT patients include high frequency oscillatory ventilation, nitric oxide and RRT. Surfactant use is less common and ECMO use is rare. Conclusion: There is a notable variation in the level of monitoring and support offered on pediatric HSCT units as well as therapies provided by PCCM physicians to HSCT patients. Not only is this data is important for the design of clinical trials, but studies should be done to determine if these practice variations impact patient outcomes. We compared outcomes of allogeneic stem cell transplantation (SCT) for congenital immunodeficiency and metabolic disorders to children of a similar age who received SCT for acute leukemia in first or second complete remission. This analysis was undertaken to address a reluctance among many physicians to refer children with certain congenital immunodeficiency or metabolic disorders for early SCT. The study population includes 343 children (#5 years) with congenital immunodeficiency (129 with severe combined immunodeficiency [SCID]; 214 with non-SCID) and 354 children with metabolic disorders. This population was compared to 622 age-matched children with acute leukemia (the control population). All transplantations occurred between 1995 and 2005 and the transplant conditioning regimen was myeloablative. In univariate analysis, 5-year overall survival was higher after HLA-matched sibling donor transplants for SCID (80%), non-SCID (84%) and metabolic disorders (78%) compared to the control group (51%, p\0.001). Amongst recipients of unrelated donor SCT, 5-year overall survival was higher for non-SCID patients compared to controls (66% vs 50%, p 5 0.05). The 5-year survival rates were similar after unrelated donor SCT for SCID (41%), metabolic (51%) and good risk acute leukemia, the control group (50%). In multivariate analysis, donor type was the only factor associated with survival; mortality rates were higher after unrelated donor SCT (odds ratio 1.49, 95% CI 1.02-2.16, p 5 0.04). Further, we observed no differences in survival after unrelated donor bone marrow and cord blood SCT. The data suggest children with congenital immunodeficiency and metabolic disorders who receive an unrelated donor SCT have similar survival rates as children with good risk acute leukemia. The sub-group of children with non-SCID diseases fare the best, with a 5-year overall survival that exceeds that of age-matched patients with acute leukemia. Therefore prompt referral for SCT for these children, before mounting comorbidities render them ineligible, should be encouraged even in the absence of an HLA-matched sibling donor.