Special aspects of renal osteodystrophy in children.

Renal osteodystrophy represents a spectrum of skeletal lesions that range from high-turnover to low-turnover bone disease. Similar factors are involved in the pathogenesis of renal osteodystrophy in adult and pediatric patients with chronic kidney disease (CKD). However, growth retardation and the development of bone deformities are specific complications that occurred in pediatric patients with CKD. Metabolic acidosis, renal osteodystrophy, malnutrition, and disturbances in the insulin growth factor (IGF)/growth hormone (GH) are among the main factors involved and they are discussed briefly in this article. In addition to disturbances in bone remodeling, longitudinal bone growth occurs at the growth plate cartilage by endochondral ossification. Although young rats with experimental CKD have growth retardation, the characteristics of the growth plate are markedly different between animals with severe secondary hyperparathyroidism and those with calcium-induced adynamic osteodystrophy. These disturbances may suggest potential molecular mechanisms by which endochondral bone formation may be altered in renal failure, consequently leading to growth retardation.