Skeletal effects and growth in children with chronic kidney disease: a 5-year prospective study

Bone Turnover Markers in Children: From Laboratory Challenges to Clinical Interpretation

Bone turnover markers (BTMs) have been developed many years ago to study, in combination with imaging techniques, bone remodeling in adults. In children and adolescents, bone metabolism differs from adults since it implies both growth and bone remodeling, suggesting an age- and gender-dependent BTM concentration. Therefore, specific studies have evaluated BTMs in not only physiological but also pathological conditions. However, in pediatrics, the use of BTMs in clinical practice is still limited due to these many children-related specificities. This review will discuss about physiological levels of BTMs as well as their modifications under pathological conditions in children and adolescents. A focus is also given on analytical and clinical challenges that restrain BTM usefulness in pediatrics.

A 3-year longitudinal study of skeletal effects and growth in children after kidney transplantation

This prospective study investigated growth and skeletal development for 3 years after kidney transplantation in pediatric patients, 3.4-15.0 years of age. Growth, BMD, bone resorption markers (CTX and TRACP5b), bone formation markers (PINP, ALP, and osteocalcin), PTH, and vitamin D were assessed at start, 3, 12, and 36 months after transplantation. Median GFR was 63 (range 37-96) mL/min/1.73 m2 after 3 years. The median height SDS increased from -1.7 to -1.1, and median BMI SDS increased from -0.1 to 0.6 over 3 years, which shows that transplantation had a favorable outcome on growth. Fat mass increased after transplantation at all time points, whereas lean mass increased after 1 year and 3 years. Total BMC increased at all time points. No changes were observed for total BMD. Bone resorption markers decreased initially after 3 months and remained stable throughout the study, whereas the bone formation markers decreased initially, but successively increased over the study period. In conclusion, this study demonstrates that height SDS and BMI SDS increased, along with the increased formation markers that reveal a positive bone acquisition after kidney transplantation, which was reflected by the significant increase in total body BMC.