Evolution of secondary hyperparathyroidism after renal transplantation

Renal osteodystrophy is an important problem in children with chronic renal failure, leading to skeletal deformities. The most-frequent type of renal osteodystrophy is secondary hyperparathyroidism, and the main factors contributing to the pathogenesis of this condition are completely or partially corrected after successful renal transplantation. The present paper reviews data on the evolution of secondary hyperparathyroidism after transplantation. Studies in both adults and children suggest that secondary hyperparathyroidism and increased bone remodelling activity may persist months after transplantation. The severity of secondary hyperparathyroidism prior to transplantation, the duration of dialysis, and the development of nodular and/or monoclonal hyperplasia of parathyroid glands are the most-important factors that determine the phenomenon. Important issues, which still need to be answered, are the possible roles of growth factors, cytokines, VDR gene polymorphism (B/b allele), and type of immunosuppressive regimen in the skeletal abnormalities observed.