Bone Abstracts

Objectives: Children and adolescents with chronic kidney disease (CKD) are at risk of developing CKD-mineral bone disorder (CKD-MBD). This study was designed to follow Swedish pediatric patients prospectively for 3 years after kidney transplantation regarding growth and skeletal development.

Methods: The study group comprised 13 patients (4 females), 4–15 years of age. Growth, bone mineral density (BMD) and markers of bone and mineral metabolism were investigated at start, and after 3, 12, 36 months after kidney transplantation.

Results: Median glomerular filtration rate was 63 (range 37–96) ml/min/1.73 m² after 3 years. The median height standard deviation score (SDS) increased from −1.7 to −1.1 after 3 years, P=0.0012, and median BMI SDS increased from −0.1 to 0.6 after 3 years, P=0.013, which implies that transplantation had a favorable outcome on growth. Total BMC increased at all time points in comparison with the initial values at study start, P<0.001. No change was observed for total BMD, calcaneal BMC and BMD over the study period. A delayed median bone age was found at start and after 3 years post-transplantation. Parathyroid hormone, phosphate and magnesium decreased at 3 months, and decreased further during the study period. The bone resorption markers tartrate-resistant acid phosphatase isoform 5b (TRACP5b) and carboxy-terminal cross-linking telopeptide of type I collagen (CTX) decreased initially after 3 months (P<0.05), and remained stable throughout the study period. The bone formation markers alkaline phosphatase, intact amino-terminal propeptide of type I procollagen (PINP) and osteocalcin decreased initially, but successively increased over the study period.

Conclusion: This study demonstrates that height SDS and BMI SDS increased, along with the increased markers of bone formation that reveals a positive bone acquisition after kidney transplantation, which was reflected by the significant increase in total body BMC.

Disclosure: The authors declared no competing interests.