Continuous renal replacement therapy in children post-hematopoietic stem cell transplantation: the present and the future

Allogeneic hematopoietic stem cell transplantation (HSCT) use has expanded markedly to treat different disorders like hematologic malignancies, immunodeficiency, and inborn errors of metabolism. However, it is commonly associated with complications that limit the benefit of this therapy. Acute renal failure occurs commonly after HSCT and results in increased risk of mortality. In many instances, children post-HSCT develop acute renal insufficiency in the context of other organ failure, necessitating intensive care unit admission for management. Recently, continuous renal replacement therapy (CRRT) has emerged as the favored modality of renal replacement therapy in the care of critically ill children who are hemodynamically unstable. Currently, CRRT is being utilized more often in the care of critically ill post- HSCT children to treat renal failure or to prevent fluid overload (FO). FO > 20% has been shown in many studies to be an independent risk of mortality in critically ill children and therefore, many clinicians will initiate this therapy due to FO even without overt renal failure. CRRT may be beneficial in disease processes as acute lung injury due to removal of fluid. CRRT results in improved oxygenation in post-HSCT children with acute lung injury and this improvement is sustained for at least 48 hours after initiation of this therapy. Survival in post-HSCT children requiring this therapy ranges from 17% to 45%, however, long term survival is still poor. This review will discuss current practice of CRRT in children post-HSCT, as well as future directions.