Bone loss and vitamin D deficiency in children undergoing hematopoietic cell transplantation

Area of Science:

• Pediatric Hematology
• Bone Metabolism
• Endocrinology

Background:

• Hematopoietic cell transplantation (HCT) is a critical treatment for various pediatric conditions.
• HCT can negatively impact bone health and vitamin D levels in children.
• Understanding these effects is crucial for improving post-transplant care.

Purpose of the Study:

• To investigate changes in bone health markers and vitamin D status in children during the initial 100 days after allogeneic HCT.
• To quantify the extent of bone mineral density (BMD) and bone mineral content (BMC) changes.
• To assess the prevalence and severity of vitamin D deficiency post-HCT.

Main Methods:

• A prospective, multicenter cohort study involving 26 children undergoing allogeneic HCT.
• Measurements of BMD, BMC, and serum 25-hydroxyvitamin D (25OHD) were taken at baseline, 30 days, and 100 days post-HCT.
• Statistical analyses, including repeated-measures analysis, were used to identify significant changes, adjusted for various confounding factors.

Main Results:

• Bone mineral density (BMD) and bone mineral content (BMC) Z-scores significantly declined within 100 days post-HCT, despite normal baseline values.
• Serum 25-hydroxyvitamin D (25OHD) concentrations decreased significantly, with 50% of patients exhibiting vitamin D deficiency (<20 ng/ml) by day 100.
• These declines were observed after adjusting for age, sex, Tanner stage, lean mass, fat mass, energy intake, insulin sensitivity, phosphorus, and steroid use.

Conclusions:

• Allogeneic HCT in children is associated with substantial bone loss and vitamin D deficiency in the first 100 days.
• There is an urgent need for interventions to prevent or reduce acute bone loss in pediatric HCT recipients.
• Monitoring and management of bone health and vitamin D status are essential components of post-HCT care for children.