A Randomized Trial of Vitamin D Supplementation With or Without Vitamin A in Stem Cell Transplantation

The investigators' preliminary data suggest that low levels of vitamin A directly impact risk
of mucosal barrier injury laboratory-confirmed bloodstream infection (MBI-LCBI) and they
believe supplemental vitamin A at the time of hematopoietic stem cell transplantation (HSCT)
can reduce the risk of MBI-LCBI and gastrointestinal graft versus host disease (GI GVHD). In
addition, the investigators' preliminary data suggest that a significant number of patients
requiring HSCT have vitamin D deficiency even prior to transplantation, and that persistent
and newly developed deficiency post-HSCT resulted in worse outcomes.

This study is a comparison of vitamin D supplementation comparing a single large dose of
vitamin D "stoss therapy" with a placebo in the standard care arm with supplementation with
single large doses of both vitamins D and A in the experimental arm. Participants will be
randomly assigned to either the standard care arm or the experimental arm.

Inclusion Criteria:

- Scheduled for allogeneic stem cell transplant

- Vitamin D level < 50 ng/ml

- Vitamin A level < 75th centile for age

- Able to tolerate enteral vitamin dose administration

Exclusion Criteria:

- History of pathologic fractures

- Known history of nephrocalcinosis or nephrolithiasis

- Current granulomatous disease

- ALT > 10X ULN for age prior to administration of vitamin A

- Ongoing raised intracranial pressure

- Pregnancy