Comorbidities and complications including infection, organ system toxicity, graft-versus-host disease (GVHD) and disease recurrence are some of the biggest contributors to quality of life and mortality in children undergoing hematopoietic stem cell transplant (HSCT). Research has suggested that patients with sufficient vitamin D levels during transplant have improved outcomes, including lower incidences of infection and acute GVHD, as well as overall improved survival. Prior research has shown that chronically ill children are at risk for vitamin D deficiency, including those undergoing HSCT. Data has shown populations with as many as 70% of HSCT patients have insufficient levels of vitamin D at time of transplant. While several studies have attempted methods of vitamin D supplementation in this subset of patients, there has not been success with either standard or aggressive supplementation strategies.
Single high-dose oral vitamin D therapy, known as stoss therapy, has been used in other chronically ill children where adequate levels of vitamin D are difficult to attain. Stoss therapy suggests a single high-dose followed by maintenance dosing would be adequate to replete and maintain vitamin D levels in chronically ill children. While it has been shown to be effective with no evidence of toxicity in patients with rickets and cystic fibrosis, its safety and efficacy has not been studied in the transplant setting. However, there is an urgent need to identify a modifiable factor may reduce the occurrence and/or severity of HSCT associated complications. The overall objective of this study is to determine the effectiveness of a single, high dose oral vitamin D (Stoss Therapy) followed by maintenance supplementation in children undergoing HSCT. This change will result in a new and innovative approach to maintaining adequate vitamin D levels during pediatric HSCT, with the long term goal of reducing morbidity and mortality.
Our primary goal is to assess the safety and efficacy of a single, high dose of vitamin D followed by maintenance supplementation in children undergoing HSCT. Our secondary goal is to identify the effects of adequate vitamin D levels on early clinical outcomes such as cytokine levels, graft versus host disease, immune recovery, rejection, relapse, infection rates in pediatric HSCT patients.
