Renal osteodystrophy represents a spectrum from high- to low-turnover bone lesions. The specific pattern, however, may change during selected therapeutic interventions. As in the past,
osteitis fibrosa remains the most frequent histologic lesion in pediatric patients on dialysis, although recently the prevalence of low-turnover bone lesions without
aluminum toxicity has been increasing in the pediatric population. This may be a consequence of aggressive
calcitriol and
calcium therapy. The different factors involved in the development of
secondary hyperparathyroidism include
hyperphosphatemia,
hypocalcemia, altered
vitamin D synthesis, impairments in
parathyroid hormone (PTH) secretion and metabolism, and, recently, possible downregulation of renal PTH/PTH-rP
messenger RNA receptor. New developments in molecular biology have demonstrated the relationship between
vitamin D and PTH. The use of high-dose pulse intravenous, intraperitoneal, and oral
calcitriol therapy has significantly decreased serum PTH levels and retarded the progression of
osteitis fibrosa. These therapeutic interventions, however, may have led to the development of adynamic bone lesions. The impact of adynamic bone lesions in the young and growing skeleton remains to be determined.