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

This study was designed to follow the evolving process of growth, bone modeling and remodeling in children with chronic kidney disease (CKD) who are at risk of developing CKD-mineral bone disorder (CKD-MBD). Fifteen patients, 4-15 years, were included with a median glomerular filtration rate of 46 (range 12-74) mL/min/1.73 m(2). Growth, bone mineral density (BMD) and markers of bone and mineral metabolism were investigated over a 5-year period. The median height standard deviation score was -0.65 at the start and 0.1 after 5 years, with a range from -1.7 to 1.7, which implies that growth was acceptable. Total body, femoral neck, and lumbar spine BMD increased over the study period (p < 0.0001). None had total body BMD Z-scores and lumbar spine Z-scores below -2.0 at follow-up. Most bone markers were within the reference intervals, but the formation markers of alkaline phosphatase and type I procollagen intact amino-terminal propeptide (PINP) were slightly increased in about one-third of the patients after 5 years. Eleven out of 15 CKD patients had increased parathyroid hormone levels at baseline and 10 patients after 5 years had increased parathyroid hormone levels. Taken together, this is the first 5-year longitudinal study of skeletal effects, growth and bone turnover in children with CKD. Growth and BMD Z-scores were well preserved on a group basis; however, these parameters varied significantly on an individual basis. We suggest, therefore, that it is difficult to state an overall recommendation and growth, bone mass, and markers of bone and mineral metabolism should be monitored and treated individually in CKD children.