Renal osteodystrophy in children with chronic renal failure: an unexpectedly common and incapactating complication.

The incidence, age at onset, and progression of the biochemical, radiographic, and histologic characteristics of renal osteodystrophy were studied in 50 children in whom chronic renal failure had been recently diagnosed. During a ten-year observation period, 19 patients progressed to end-stage renal failure and radiographic signs of renal osteodystrophy developed in 15 of these (79%). Renal osteodystrophy developed in all nine patients whose chronic renal failure was diagnosed before 3 years of age and in six of the ten children with later onset of failure. The mean interval from diagnosis of renal failure to development of osteodystrophy was 1.4 years. Radiographically, growth zone lesions predominated in the younger children, whereas cortical erosions were more prevalent in the older children. Histologic examination, performed in 38 patients, showed both defective mineralization and excessive resorption and was a more sensitive diagnostic index than radiography. Noticeable deformities developed in one third of the patients with osteodystrophy, despite medical treatment including vitamin D2 therapy. Deformities were particularly frequent and severe in patients whose renal failure developed in infancy. In all 13 patients whose growth patterns were studied before and after osteodystrophy developed, the onset of bone lesions was associated with a deterioration of growth, indicating that osteodystrophy plays a major role in causing the growth retardation commonly observed in children with chronic renal failure.